GOST 8.354-85

Group T88.5

STATE STANDARD OF THE USSR UNION

State system for ensuring the uniformity of measurements

CONDUCTOMETRIC LIQUID ANALYZERS

Verification method

State system for ensuring the uniformity
of measurements. Conductometric liquid analyzers.
Methods of verification

OKSTU 0008

Date of introduction 1987-01-01

DEVELOPED by the USSR State Committee for Standards

PERFORMERS

Y.N.Mudzhiri, G.V.Chanishvili, N.N.Ratianidze, L.S.Gudushauri

INTRODUCED by the USSR State Committee for Standards

Member of Gosstandart L.K.Isaev

APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee on Standards dated November 13, 1985 N 3591

INSTEAD GOST 8.354-79


This standard applies to conductometric liquid analyzers (hereinafter referred to as analyzers) for general industrial use, manufactured in accordance with GOST 13350-78, intended for measuring specific electrical conductivity (hereinafter referred to as SEC) and concentration of liquids, for which an unambiguous relationship between their specific electrical conductivity and composition is standardized, and establishes the methodology for primary and periodic verification.

1. VERIFICATION OPERATIONS

1. VERIFICATION OPERATIONS

1.1. When performing verification, the following operations must be performed:

external inspection (clause 4.1);

testing (clause 4.2);

determination of the main error (clauses 4.3; 4.4);

determination of changes in readings (output signals) from changes in the temperature of the analyzed liquid (clause 4.5).

2. MEANS OF VERIFICATION

2.1. When conducting verification, the following means must be used:

installation type UPKK-2 (see reference appendix 2);

installation type UPS-1 (see reference Appendix 3);

resistance store according to GOST 23737-79 accuracy class from 0.05 to 0.2 depending on the accuracy of the analyzer being verified;

standard voltmeters and milliammeters providing voltage and force measurements direct current in the ranges according to GOST 26.011-80; accuracy class not lower than 0.05-0.4, depending on the accuracy of the analyzer being verified;

mercury glass laboratory thermometers TL N 2 and 3 according to GOST 215-73;

laboratory scales of the 2nd accuracy class according to GOST 24104-80*;
__________________
* In the territory Russian Federation GOST 24104-2001 is valid. - Note "CODE".

potassium chloride, grade "ch" according to GOST 4234-77;

sodium chloride, grade "grade" according to GOST 4233-77;

distilled water according to GOST 6709-72.

2.2. The ratio of the main errors of standard verification tools and verified analyzers should be no more than 1:3 when calibrating analyzers with a permissible limit of main errors of 1.0% or more, and no more than 1:2 when calibrating analyzers with a permissible limit of main errors of less than 1.0%.

When calibrating analyzers that have output electrical signals, the error of the standard verification means is taken to be the geometric sum of the errors of the standard analyzer and the standard device that measures the output signal.

2.3. It is allowed to use other newly developed or in use verification tools that meet the requirements of this standard and have passed metrological certification by the state metrological service.

3. CONDITIONS OF VERIFICATION AND PREPARATION FOR IT

3.1. When performing verification, the following must be observed: normal conditions according to GOST 13350-78.

3.2. Before carrying out verification, the following must be completed: preparatory work:

verification tools and analyzers being verified are prepared for work in accordance with the requirements of their technical documentation;

when checking analyzers that have electrical output signals, a corresponding reference device is connected to their output;

Before determining the metrological characteristics, the necessary adjustment of the analyzers being verified is carried out, as provided for in the technical documentation.

The preparation of solutions and the connection of the primary converter of the analyzer being verified to the circuit are carried out according to the technical documentation for the installation.

4. VERIFICATION

4.1. Visual inspection

4.1.1. During an external inspection, it must be established that the analyzer being verified meets the following requirements:

the analyzer must be presented for verification with a passport (form) and technical description;

The completeness of the analyzer during initial and periodic verification must correspond to the completeness specified in the passport;

Analyzers must be free of the following defects that lead to measurement errors:

malfunction of controls (buttons, switches, handles), connectors, clamps, terminals, fittings, connecting and connecting wires, cables and hydraulic lines, contamination of dials and digital displays;

unclear inscriptions and markings;

damage to the housing and outward-facing structural elements (in particular, the electrodes of submerged primary transducers);

leakage of liquid from internal cavities and flow-through primary converters.

4.2. Testing

4.2.1. When testing the analyzer, the following must be checked:

the ability to install controls and adjustments in any of the provided positions, smooth operation, absence of jamming and reliability of fixation in the installed position;

serviceability of the signaling device for turning on the analyzer to the power supply and compliance rated current fuse to the required value;

the ability to set any indication (output signal value) in all measurement ranges by simulating the analyzed medium or primary transducer;

technical condition of the analyzers according to other parameters provided for in the technical documentation for it.

4.3. Determination of the main error using the complete method

4.3.1. The main error of the analyzer is determined in its entirety by comparing the readings (values ​​of the electrical conductivity or composition corresponding to the measured values ​​of the output signal) of the analyzer being verified with the readings of a standard conductivity meter when checking the analyzer-conductivity meter directly, and when checking the analyzer-concentrator with the composition values ​​determined from the readings of the standard conductivity meter in accordance with normalized relationship between the UEP and the composition of the analyzed liquids.

The main error is determined using calibration solutions that have a specific electrical conductivity corresponding to the measurement range of the analyzer being verified at normal temperature for the liquid being analyzed.

4.3.2. Measurements are carried out sequentially from smaller to larger SEP values. In the case of a fillable primary converter, a sample of the analyzed liquid is taken from the tank in a volume that ensures three times washing and filling of the primary converter of the standard conductometer. The primary transducer filled with the liquid being analyzed is immersed in a glass of distilled water and placed in a tank for thermostatting.

When using a UPS-1 type installation, it is allowed to use a standard conductivity meter with a flow-through design of the primary converter in order to avoid contact with the atmosphere.

4.3.4. The main error is determined at three points corresponding to approximately 20, 50 and 80% of the measurement range (subrange).

4.3.4. The UEP (reading reading) is measured when a stable temperature of the analyzed solution is established in the primary converters of the analyzer being verified and the standard conductivity meter, which is judged by the constancy of the readings for a time sufficient to take the readings (not less than 1 minute and not more than 30 minutes).

When assessing the error, it is allowed not to take into account the results obtained using a standard conductivity meter if they differ from each other by more than 0.3 of the main error of the analyzer being verified. In this case, repeat measurements are carried out until three matching results are obtained within the specified error limits.

4.3.5. The systematic component of the main error according to GOST 13350-78 is determined by the formulas

where is the number of measurements at each point (3),

where is the measured value of the UEP obtained on the analyzer being verified, S/m;

- actual value of electrical conductivity obtained on a standard conductivity meter, S/m;

- normalizing value of the UEP specified in the technical documentation for the analyzer being verified, S/m.

The main error is assessed by the largest of the obtained values, which should not exceed the limits specified in the technical documentation for the analyzer being verified.

4.4. Determination of the main error by element-by-element method

4.4.1. The main error in the UEP range of more than 30 S/m and less than 10 S/m is determined using electrical simulators element by element: the main error of the analyzer measuring unit and the constant of the primary transducer are determined.

4.4.2. The constant of the primary converter is determined at least three times in one of the measurement ranges (subranges) according to the tables of reference Appendix 4.

4.4.2.1. The value of the electrical conductivity of the selected solution is determined using a standard conductivity meter after thermal equilibrium has been established. At the same time, the reading of the measuring unit of the analyzer is recorded.

4.4.2.2. The primary transducer of the analyzer is replaced with a resistance store and by selecting the resistance on it, the readings of the measuring unit of the analyzer are obtained that correspond to the readings obtained from the solution.

4.4.2.3. The analyzer primary converter constant is determined by the formula

where is the SEP value according to a standard conductivity meter, S/m;

- value of simulating resistance, Ohm.

The arithmetic mean of the results of three measurements is taken as the constant of the sensitive element of the analyzer,

4.4.2.4. The error in determining the constant of the analyzer primary converter is estimated using the formula

where * is the value of the primary converter constant, calculated using formula 3, m.

* - value of the constant according to the technical documentation for the analyzer, m.
________________


The error in determining the constant of the primary converter should not exceed the value specified in the technical documentation.

4.4.3. The main error of the analyzer measuring unit is determined by replacing the primary transducer with a simulating resistance at three points, corresponding to approximately 20, 50 and 80% of each range (subrange).

4.4.3.1. The value of simulating resistances for each of the points being tested is determined by the formula

where is the UEP value corresponding to each checked point on the scale, S/m;

* - constant of the primary converter, determined according to the method of clause 4.4.2.3, m.
________________
* The formula and its explanation correspond to the original. - Note "CODE".

4.4.3.2. The systematic component of the main error is determined by formulas (1) and (6)

where is the UEP value on the analyzer scale corresponding to the point being tested, S/m;

- measured value of the electrical resistivity corresponding to the simulating resistance, S/m.

4.4.3.3. It is allowed to determine the main error by the element-by-element method according to the methodology set out in clause 4.4 and in other ranges of the electrical power, as well as in justified cases using a method that differs from that set out in clause 4.4.

4.5. Determination of changes in readings (output signals) depending on changes in the temperature of the analyzed liquid

4.5.1. The change in readings (output signals) from changes in the temperature of the analyzed medium is determined using working solutions at three points of each range (subrange) specified in clause 4.3.3, when the temperature of the analyzed medium changes by ±15 °C from the working temperature value.

4.5.2. Changes in readings (output signals) depending on changes in the temperature of the analyzed liquid are determined by the formula

where is the value of the electrical conductivity at operating temperature, S/m;

- UEP value at a temperature different from the operating temperature by ±15 °C.

4.5.3. The change in the analyzer readings due to a change in the temperature of the analyzed medium by ±15 °C from the operating temperature should not exceed the permissible value of the basic error of the analyzer being verified.

4.6. The verification results are recorded in the verification protocol given in the mandatory Appendix 1.

5. REGISTRATION OF VERIFICATION RESULTS

5.1. Positive results The manufacturer formalizes the initial verification of analyzers with an entry in the passport, certified by the verifier, with an imprint of the verification stamp.

5.2. Positive results of periodic verification of analyzers carried out by the state metrological service, are formalized by stamping and issuing a certificate in the form established by Gosstandart.

5.3. Positive results of periodic verification of analyzers carried out by the departmental metrological service are documented in the manner established by the departmental metrological service.

5.4. Analyzers that have passed verification with a negative result are not allowed to be released into circulation or for further use: the marks on them are canceled and a notice of unsuitability is issued. The verification certificate will be cancelled.

APPENDIX 1 (mandatory). FORM OF VERIFICATION PROTOCOL

ANNEX 1
Mandatory

PROTOCOL N

MEANS OF VERIFICATION APPLIED

CONDITIONS OF VERIFICATION:

VERIFICATION RESULTS

b) by electrical simulators

4. Determination of changes in readings (output signals) from changes in the temperature of the analyzed medium

APPENDIX 2 (for reference). DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTION OF OPERATION OF THE UPKK-2 TYPE INSTALLATION

APPENDIX 2
Information

1 - pump; 2 - tank of flow primary converters; 3 - fridge; 4 - submersible tank
primary converters; 5 - flow primary converter; 6-8 - three-way valves;
9 - resistance thermometer; 10 - thermostat; 11 - coil

Specifications installations

The working medium is aqueous solutions of sodium or potassium chloride.



The range of UEP of solutions circulating in the system is 1·10-100* S/m.
________________
* Corresponds to the original. - Note "CODE".

Temperature instability of the working environment is ±0.2 °C.





Mains power alternating current voltage 220 V%, frequency (50±1) Hz.

Description of the installation

Flow primary converter 5 installed on flanges selected depending on their diameter from the set of installation accessories. The submersible primary converter is placed in the tank of submersible primary converters 4.

The hydraulic system of the installation is filled with a solution of potassium chloride or sodium through a tank 2 or 4 . The required solution concentration is achieved by dissolving in distilled water. required quantity salt (see reference Appendix 4), recalculated for the working volume of the analyzed medium.

Turning on the pump 1 ensure circulation of the solution in the system.

Depending on the specified temperature regime checks include thermostat 10 or refrigerator 3 and set the temperature corresponding to the one selected from Table 1 or 2 of Reference Appendix 4.

The temperature of the solution is controlled using an electronic bridge complete with a resistance thermometer 9 .

After establishing the set temperature, adjust the concentration by adding to the tank 2 or 4 water or a more concentrated salt solution until the analyzer readings coincide with the digitized point. The concentration is measured gradually until the temperature and concentration are equalized. At other points being checked, verification is carried out as described above.

APPENDIX 3 (for reference). DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTION OF OPERATION OF THE UPS-1 TYPE INSTALLATION

APPENDIX 3
Information

1-4 - tanks; 5-6 - pumps; 7 - ion exchange columns; 8 - tap for sampling the solution; 9 - verified
primary converter; 10, 13, 15, 18, 19, 20, 22 - valves; 11 - thermostat;
12 - resistance thermometer; 14, 16, 17 - funnels for filling; 21, 23 - funnels with soda lime

1. Technical characteristics of the installation

Working medium - distilled water, aqueous solutions of sodium chloride.

The range of UEP of solutions circulating in the system is 1·10-1·10 S/m (in units of conventional concentration of sodium chloride - 0-1000 mg/l).

The temperature range of the working environment is 5-80 °C.

Temperature instability of the working environment ±0.2 °C.

The time to establish stable concentration readings from the analyzer being verified is 30 minutes.

The time to establish a stable temperature of the working environment is 30 minutes.

Power supply from AC mains voltage 220 V%, frequency (50±1) Hz.

Power consumption - no more than 2 kW.

2. Description of the installation

The analyzer is turned on and warmed up for 20 minutes.

Fill the tank with distilled water 1 and open the valves 15 And 19 ion exchange column 7 . After filling the tank 2 close the valve 19 , open the valve 13 , turn on the pump and fill the tank 3 . Pump 5 turn off.

Tank 4 filled with a sodium chloride solution with a concentration an order of magnitude higher than the concentration of the range being verified (see Table 1 or 2 of Reference Appendix 4). Turn on the pump 6 , ensuring circulation of the solution in a closed system.

Turn on the thermostat 11 and using the temperature setter of the electronic bridge, set the temperature corresponding to the operating temperature of the analyzer being verified.

Then change the concentration by adding water or salt solution and adjust the valves 22 or 18 until the analyzer readings coincide with the digitized point being tested. The concentration is changed gradually until the temperature and concentration are equalized.

At the remaining points being checked, the test is carried out as described above.

To take a sample of the solution on a standard device, use tap 8.

APPENDIX 4 (for reference). DEPENDENCE OF SPECIFIC ELECTRICAL CONDUCTIVITY OF SODIUM AND POTASSIUM CHLORIDE SOLUTIONS ON CONCENTRATION AND TEMPERATURE

APPENDIX 4
Information

Table 1

table 2

The text of the document is verified according to:
official publication
M.: Standards Publishing House, 1986

GOST 8.354-85 instead of GOST 8.354-79 by resolution state committee USSR according to standards dated November 13, 1985 No. 3591, the introduction period is set from 01/01/87, this standard applies to conductometric liquid analyzers (hereinafter referred to as analyzers) for general industrial use, manufactured in accordance with GOST 13350-78, intended for measuring specific electrical conductivity (hereinafter referred to as uep) and concentration of liquids, for which an unambiguous relationship between their specific electrical conductivity and composition is standardized, and establishes the methodology for primary and periodic verification. 1. verification operations

GOST 8.354-85
Instead of GOST 8.354-79
By Decree of the USSR State Committee on Standards dated November 13, 1985 No. 3591, the introduction date was established
from 01/01/87
This standard applies to conductometric liquid analyzers (hereinafter referred to as analyzers) for general industrial use, manufactured in accordance with GOST 13350-78, intended for measuring specific electrical conductivity (hereinafter referred to as SEC) and the concentration of liquids for which there is a standardized, unambiguous relationship between their specific electrical conductivity and composition , and establishes the methodology for initial and periodic verification.
1. VERIFICATION OPERATIONS
1.1. When performing verification, the following operations must be performed:
external inspection (clause 4.1);
testing (clause 4.2);
determination of the main error (clauses 4.3; 4.4);
determination of changes in readings (output signals) from changes in the temperature of the analyzed liquid (clause 4.5). "
2. MEANS OF VERIFICATION
2.1. When conducting verification, the following means must be used: *
installation type UPKK-2 (see reference appendix 2); installation type UPS-1 (see reference Appendix 3);

Page 2 GOST 8.354-85
resistance store according to GOST 23737-79 accuracy class from 0.05 to 0.2 depending on the accuracy of the analyzer being verified;
standard voltmeters and milliammeters that provide measurement of voltage and direct current in the ranges in accordance with GOST 26.011-80; accuracy class not lower than 0.05 _ 0.4 depending on the accuracy of the analyzer being verified;
mercury glass laboratory thermometers TL No. 2 and 3 according to GOST 215-73; .
laboratory scales of the 2nd accuracy class according to GOST 24104 - 80;
potassium chloride, grade “grade” according to GOST 4234-77;
sodium chloride, grade “grade” according to GOST 4233-77;
distilled water according to GOST 6709-72.
2.2. The ratio of the main errors of the reference tools and the analyzers being verified should be no more than 1:3 when calibrating analyzers with a permissible limit of main errors of 1.0% or more, and no more than 1:2 when calibrating analyzers with a permissible limit of main errors of less than 1.0%.
When checking analyzers that have output electrical signals, the error of the standard verification means is taken to be the geometric sum of the errors of the standard analyzer and the standard device that measures the output signal.
2.3. It is allowed to use other newly developed or in use verification means that meet the requirements of this standard and have passed metrological certification >in the state metrological service.
3. CONDITIONS CHECKS AND PREPARATION FOR HER
3.1. When performing verification, normal conditions in accordance with GOST 13350-78 must be met.
3.2. Before carrying out verification, the following preparatory work must be completed: "
verification tools and verified analyzers are prepared for work in accordance with the requirements of their technical documentation;- ;
when checking analyzers that have electrical output signals, a corresponding reference device is connected to their output;
Before determining the metrological characteristics, the necessary adjustment of the analyzers being verified is carried out, as provided for in the technical documentation. w
The preparation of solutions and the connection of the primary converter of the analyzer being verified to the circuit are carried out according to the technical documentation for the installation.

GOST 8.354-“5 Page. 3
4. VERIFICATION
4.1. Visual inspection
4.1.1. During an external inspection, it must be established that the analyzer being verified meets the following requirements: I
the analyzer must be presented for verification with its passport; (form) and technical description;
The completeness of the analyzer during initial and periodic verification must correspond to the completeness specified in the passport;
Analyzers must be free of the following defects that lead to errors in measurements: ,
malfunction of controls (buttons, switches, handles), connectors, clamps, terminals, fittings, connecting and connecting wires, cables and hydraulic lines, contamination of dials and digital displays;
unclear inscriptions and markings;
damage to the housing and outward-facing structural elements (in particular, the electrodes of submerged primary transducers);
leakage of liquid from internal cavities and flow-through primary converters. \
4.2. Testing \
4.2.1. When testing the analyzer, the following must be checked:
the ability to install controls and adjustments in any of the provided positions, smooth operation, absence of jamming and reliability of fixation in the installed position;
serviceability of the signaling device for turning on the analyzer to the power supply network and compliance of the rated fuse current with the required value;
the ability to set any indication (output signal value) in all measurement ranges by simulating the analyzed medium or primary transducer;
technical condition of the analyzers according to other parameters provided for in the technical documentation for it. \
4.3. Determination of the main error using the complete method
4.3.1. The main error of the analyzer is determined in its entirety by comparing the readings (values ​​of the electrical conductivity or composition corresponding to the measured values ​​of the output signal) of the analyzer being verified with the readings of a standard conductivity meter when checking the analyzer-conductivity meter directly, and when checking the analyzer-concentrator with the composition values ​​determined from the readings of a standard conductivity meter in accordance with normalized relationship between the UEP and the composition of the analyzed liquids. >

Page 4 GOST 8.354-85
The main error is determined using calibration solutions that have a UES corresponding to the measurement range of the analyzer being verified at normal temperature for the liquid being analyzed., \"
4.3.2 Measurements are carried out sequentially from smaller to larger SEP values. In the case of a fillable primary converter, a sample of the analyzed liquid is taken from the tank in a volume that ensures three times washing and filling of the primary converter of the standard conductometer. The primary transducer, filled with the analyzed liquid, is immersed in a glass with distilled water and placed in a tank for thermostatting.
When using a UPS-1 type installation, it is allowed to use a standard conductivity meter with a flow-through design of the primary converter in order to avoid contact with the atmosphere.
4.3.4. The main error is determined at three points corresponding to approximately 20, 50 and 80% of the measurement range (subrange)^
4.3.4. The UEP (reading reading) is measured when a stable temperature of the analyzed solution is established in the primary converters of the analyzer being verified and the standard conductivity meter, which is judged by the constancy of the readings for a time sufficient to take the readings (not less than 1 minute and not more than 30 minutes).
It is allowed not to take into account the results obtained using a standard conductivity meter when assessing the error if: they differ from each other by more than 0.3 times the main error of the analyzer being verified. In this case, repeated measurements are carried out until three matching results are obtained within the specified error limits.
4.3.5. The systematic component of the main error 1 A according to GOST 13350-78 is determined by the formulas
A^i-SA, (1)
P 1=1 Where P- number of measurements at each point (i>3)„
D| _5^=5..100, (2)
Lnormal
Where x change
X normal
measured value of the UEP obtained on the analyzer being verified, S/m;
actual value of electrical conductivity obtained on a standard conductivity meter, S/m;
normalizing value of UEP specified in the technical
documentation for the analyzer being verified, Sm/m.

GOST 8.354-85 Page 5
The main error is assessed by the largest of the obtained values, which should not exceed the limits specified in the technical documentation for the analyzer being verified. "
4.4. Determination of the main error using the element-by-element method!
4.4.1. The main error in the UEP range of more than 30 S/m and less than 10 -4 S/m is determined using electrical simulators element by element: the main error of the analyzer measuring unit and the constant of the primary transducer are determined.
4.4.2. The constant of the primary converter is determined at least three times in one of the measurement ranges (subranges) according to the tables of reference Appendix 4.
4.4.2.1. The value of the electrical conductivity of the selected solution is determined using a standard conductivity meter after thermal equilibrium has been established. At the same time, the reading of the measuring unit of the analyzer is recorded. ,
4.4.2.2. The primary transducer of the analyzer is replaced with a resistance store and by selecting the resistance on it, the readings of the measuring unit of the analyzer are obtained that correspond to the readings obtained from the solution.
4.4.2.3. Constant With The primary converter of the analyzer is determined by the formula
Where X arr - value of UEP according to a standard conductivity meter, S/m;
R„ M- value of simulating resistance, Ohm. The arithmetic mean of the results of three measurements is taken as the constant of the sensitive element of the analyzer* 1
4.4.2.4. The error in determining the constant of the primary converter b of the analyzer is estimated using the formula
8= ^з_.ОО, (4)
Where WITH-value of the primary converter constant, calculated using formula 3, m -1. WITH\- value of the constant according to the technical documentation for the analyzer, m -1. The error in determining the constant of the primary converter should not exceed the value specified in the technical documentation. <"
4.4.3. The main error of the analyzer measuring unit is determined by replacing the primary transducer with a simulating resistance at three points, corresponding to approximately 20, 50 and 80% of each range (subrange). "<

Page 6 GOST 8.354-85
4.4.3.1. The value of simulating resistances for each of the points being tested is determined by the formula "
Where X- UEP value corresponding to each checked point on the scale, S/m; WITH- constant of the primary converter, determined according to the method and. 4.4.2.3, m -1.
4.4.3.2. Systematic component of the main error A c is determined by formulas (1) and (6)
D - *p-*izy, Yu0>. (6)
*NORM
Where x n- UEP value on the analyzer scale corresponding to the point being checked, S/m; 1 x nzm-measured value of the electrical resistivity corresponding to the simulating resistance, S/m.
4.4.3.3. It is allowed to determine the main error by an element-by-element method according to the methodology set out in clause 4.4 and in other ranges of the electrical power, as well as in justified cases using a method that differs from that set out in clause 4.4.
4.5. Determination of “changes in indications (output signals) depending on changes in the temperature of the analyzed liquid
4.5.1. The change in readings (output signals) from changes in the temperature of the analyzed medium is determined using working solutions at three points of each range (subrange) specified in clause 4.3.3, when the temperature of the analyzed medium changes by ±15 ° C from the working temperature value.
4.5.2. Changes in readings (output signals) D/ depending on changes in the temperature of the analyzed liquid are determined by the formula
D/(|)=-^Ts-^DSH,(7)
А()= *p-;~*p- t±15 .100; (8)
l normal
where is Chr. t - value of the electrical conductivity at operating temperature, S/m; %t±15 - value of the electrical conductivity at a temperature different from the operating temperature by ±15°C.
4.5.3. The change in the analyzer readings from a change in the temperature of the analyzed medium by ±15°C from the operating temperature should not exceed the limit of the permissible value of the basic error of the analyzer being verified.

GOST 8.354-85 Page 7
4.6. The verification results are recorded in the verification protocol given in mandatory Appendix 1. J
5. REGISTRATION OF VERIFICATION RESULTS
5.1. The manufacturer formalizes the positive results of the initial verification of the analyzers with an entry in the passport, certified by the verifier with an imprint of the verification stamp,
5.2. Positive results of periodic verification of analyzers carried out by the state metrological service are formalized by branding and the issuance of a certificate in the form established by Gosstandart.
5.3. Positive results of periodic verification of analyzers carried out by the departmental metrological service are documented in the manner established by the departmental metrological service.
5.4. Analyzers that have passed verification with a negative result are not allowed to be released into circulation or for further use: the marks on them are canceled and a notice of unsuitability is issued. The verification certificate will be cancelled.

Page 8 GOST 8.354-85
APPENDIX I Mandatory
primary
FORM OF VERIFICATION PROTOCOLPROTOCOL No.
verification ____
periodic type_________
analyzer name
№.
belonging to_____________________________________________
name of the enterprise, organization out of production (repair)_______________
or
date and name
enterprises, fill in during initial verification" Measuring range__________________________________________
MEANS OF VERIFICATION APPLIED
Name, type
Manufacturer number
Accuracy class, permissible error

Information

passing

verification

Other

characteristics

and clarifications
CONDITIONS OF VERIFICATION:
ambient air temperature......*С
relative humidity.........%
atmospheric pressure.........kPa
supply voltage.........V
supply current frequency. . . .......Hz
temperature of control solutions. . . . . . . * WITH
VERIFICATION RESULTS
1. Visual inspection , ________________________________________
2. Testing ________________________________________________
3. Determination of the main error ___________________________
I) by solutions

GOST 8.354-85 Page 9>

Range

measurements,

S/m
*ism" Sm/m
X, S/m
x normal" Sm/m
L. %
b) by electrical simulators

Range

measurements,

Sm/m
^arr. Sm/m
^im, Om
With,
-1
m
With,-1
m
V, %
Sm/m
*ism, Sm/m
^norm, . Sm/m.
L. %
4. Determination of changes in readings (output signals) from changes in the temperature of the analyzed medium

Range

measurements,

Meaning

temperature,

"WITH
WITH
X
r.t, S/m
fp.T±15. Sm/m
"norm,Sm/m
L, %
5. Conclusion_____________________________________________
prkber is valid, reject, indicate the reason
The verification was carried out by _;____________________;_________
surname, initials
":___"________19___
\

Page 10 GOST 8.E54-85
APPENDIX 2 Information
DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTION OF OPERATION OF THE UPKK-2 TYPE INSTALLATION

/_ on sos; 2-tank of flow primary converters;3 -fridge; 4-tank submersible primary converters; "5-flow primary converter; 6- 8- three-way valves; 9- resistance thermometer; 10- thermostat; //-coil
Installation specifications
The working medium is aqueous solutions of sodium or potassium chloride. The temperature range of the working environment is 5-80 °C.
The range of UEP of solutions circulating in the system is MO 2 -100 S/m. Temperature instability of the working environment is ±0.2°C.
The time to establish stable concentration readings from the analyzer being verified is 30 minutes.
Time to establish a stable temperature of the working environment - 30 min.

GOST 8.354-85 Page eleven
Power supply from AC mains voltage 220_)"%,frequency
(50 ± 1) Hz.
Power consumption - no more than 2 kW.
Description of the installation
Flow primary converter 5 is installed on flanges selected depending on their diameter from set accessories To installation. The submersible primary converter is placed in the tank of submersible primary converters 4.
The hydraulic system of the installation is filled with a solution of potassium chloride or sodium through tank 2 or 4. The required concentration of the solution is achieved by dissolving the required amount of salt in distilled water (see reference Appendix 4), recalculated for the working volume of the analyzed medium.
Turning on the pump / ensures circulation of the solution in the system.
Depending on the set temperature regime, the thermostat is turned on 10 or refrigerator 3 and set the temperature corresponding to the one selected from the table. 1 or 2 reference applications 4.
The temperature of the solution is controlled using an electronic bridge complete with a resistance thermometer 9.
After establishing the set temperature, adjust the concentration by adding to the tank 2 or 4 water or a more concentrated salt solution until coincidences analyzer readings With digitized point. The concentration is measured gradually until the temperature and concentration are equalized. At other points being checked, verification is carried out as described above.

Page 12 GOST 8.354-85
APPENDIX 3 Information
DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTIONOPERATION OF INSTALLATION TYPE UPS 1
17 23 16 23

Cooling
g~------- "M 4 -^ gore
tt

1-4- tanks; 5-6 pumps; 7-ionite columns; 8- faucet for! solution sampling; 9-verifiable primary converter; 10, 13, 15, 18, 19, 20, 22 - valves; //-thermostat; 12- resistance thermometer; 14, 16, 17- funnels for filling; 21, 23- funnels with soda lime
1. Technical characteristics of the installation
Working medium: distilled water, aqueous solutions of sodium chloride.
The range of UEP of solutions circulating in the system is 1-10-4 - MO-" S/m \V units of conventional concentration of sodium chloride - 0-1000 mg/l).
The temperature range of the working environment is 5-80 °C.

GOST 8.354-85 Page 13
Temperature instability of the working environment ±0.2 °C.
The time to establish stable concentration readings from the analyzer being verified is 30 minutes. ,
The time to establish a stable temperature of the working environment is 30 minutes.
Power supply from AC mains voltage 220 V^)!; %, frequency<50±1) Гц.
Power consumption - no more than 2 kW.
2. Description of the installation
The analyzer is turned on and warmed up for 20 minutes.
Fill the tank with distilled water and open the valves 15 And 19 ion exchange column 7. After filling tank 2, close the valve 19, open the valve 13, turn on the pump and fill the tank 3. Pump 5 is turned off.
Tank 4 filled with a sodium chloride solution with a concentration an order of magnitude higher than the concentration of the range being verified (see Table 1 or 2 of Reference Appendix 4). They turn on the pump 6, which ensures circulation of the solution in a closed system.-
Turn on the thermostat // and, using the temperature setter of the electronic bridge, set the temperature corresponding to the operating temperature of the analyzer being verified.
Then change the concentration by adding water or salt solution and adjust the valves 22 or 18 until the analyzer readings coincide with the digitized point being tested. The concentration is changed gradually until the temperature and concentration are equalized.
At the remaining points being checked, the test is carried out as described above.
To take a sample of the solution on a standard device, use tap 8.

DEPENDENCE OF SPECIFIC ELECTRICAL CONDUCTIVITY OF SODIUM AND POTASSIUM CHLORIDE ON CONCENTRATION AND THEM
Specific electrical conductivity of sodium chloride solutions
Solution concentration, g/l
20
25
30
35

55
65
25
3, 66
4, 05
4, 46

7, 04
50
6, 79
7, 48
8, 20

13, 44
100
12, 15
13, 39
14, 68

24, 42
200
19, 26
21, 17
23, 41

38, 35
300
22, 32
24, 72
27, 42

Specific electrical conductivity of potassium chloride solutions,
Concentration, solution, g/l
20
25
30
35
45
55
65
7, 5 50, 0 100 1.50 200, 0 250, 0 300, 0

1, 18 7, 05 13, 35 19, 32 25, 10 30, 27 34, 54

1, 30 7, 80 14, 60 21, 15 27, 30 32, 60 37, 24

1, 43 8, 51 15, 87 22, 85 29, 42 35, Yu 40, 11

1, 55 9, 25 17, 20 24, 60 31, 60 37, 60 42, 84
1, 807 1, 065 15, 75 28, 25 36, 00 42, 70 48, 83
2, 05 12, 0G 22, 35 31, 72 40, 05 47, 70 56, 12
2, 32 13, 51 24, 85 35, 20 44, 70 52, 50 62, 10
"

Metrology. GOST 8.354-85 - State system for ensuring the uniformity of measurements. Conductometric liquid analyzers. Verification method. OKS: Metrology and measurements. Physical phenomena, Electricity. Magnetism. Electrical and magnetic measurements. GOST standards. State system for ensuring unity.... class=text>

GOST 8.354-85

State system for ensuring the uniformity of measurements. Conductometric liquid analyzers. Verification method

GOST 8.354-85
Group T88.5

STATE STANDARD OF THE USSR UNION

State system for ensuring the uniformity of measurements

CONDUCTOMETRIC LIQUID ANALYZERS

Verification method

State system for ensuring the uniformity
of measurements. Conductometric liquid analyzers.
Methods of verification

OKSTU 0008

Date of introduction 1987-01-01

DEVELOPED by the USSR State Committee for Standards
PERFORMERS

Y.N.Mudzhiri, G.V.Chanishvili, N.N.Ratianidze, L.S.Gudushauri
INTRODUCED by the USSR State Committee for Standards
Member of Gosstandart L.K.Isaev
APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee on Standards dated November 13, 1985 N 3591
INSTEAD GOST 8.354-79

This standard applies to conductometric liquid analyzers (hereinafter referred to as analyzers) for general industrial use, manufactured in accordance with GOST 13350-78, intended for measuring specific electrical conductivity (hereinafter referred to as SEC) and concentration of liquids, for which an unambiguous relationship between their specific electrical conductivity and composition is standardized, and establishes the methodology for initial and periodic verification.

1. VERIFICATION OPERATIONS

1. VERIFICATION OPERATIONS

1.1. When performing verification, the following operations must be performed:
external inspection (clause 4.1);
testing (clause 4.2);
determination of the main error (clauses 4.3; 4.4);
determination of changes in readings (output signals) from changes in the temperature of the analyzed liquid (clause 4.5).

2. MEANS OF VERIFICATION

2.1. When conducting verification, the following means must be used:
installation type UPKK-2 (see reference appendix 2);
installation type UPS-1 (see reference Appendix 3);
resistance store according to GOST 23737-79 accuracy class from 0.05 to 0.2 depending on the accuracy of the analyzer being verified;
standard voltmeters and milliammeters that provide measurement of voltage and direct current in the ranges in accordance with GOST 26.011-80; accuracy class not lower than 0.05-0.4, depending on the accuracy of the analyzer being verified;
mercury glass laboratory thermometers TL N 2 and 3 according to GOST 215-73;
laboratory scales of the 2nd accuracy class according to GOST 24104-80*;
__________________
* GOST 24104-2001 is in force on the territory of the Russian Federation. - Note.

potassium chloride, grade "grade" according to GOST 4234-77;
sodium chloride, grade "grade" according to GOST 4233-77;
distilled water according to GOST 6709-72.

2.2. The ratio of the main errors of standard verification tools and verified analyzers should be no more than 1:3 when calibrating analyzers with a permissible limit of main errors of 1.0% or more, and no more than 1:2 when calibrating analyzers with a permissible limit of main errors of less than 1.0%.
When calibrating analyzers that have output electrical signals, the geometric sum of the errors of the standard analyzer and the standard device that measures the output signal is taken as the error of the standard verification means.

2.3. It is allowed to use other newly developed or in use verification tools that meet the requirements of this standard and have passed metrological certification by the state metrological service.

3. CONDITIONS OF VERIFICATION AND PREPARATION FOR IT

3.1. When performing verification, normal conditions in accordance with GOST 13350-78 must be met.

3.2. Before carrying out verification, the following preparatory work must be completed:
verification tools and verified analyzers are prepared for work in accordance with the requirements of their technical documentation;
when checking analyzers that have electrical output signals, a corresponding reference device is connected to their output;
Before determining the metrological characteristics, the necessary adjustment of the analyzers being verified is carried out, as provided for in the technical documentation.
The preparation of solutions and the connection of the primary converter of the analyzer being verified to the circuit are carried out according to the technical documentation for the installation.

4. VERIFICATION

4.1. Visual inspection

4.1.1. During an external inspection, it must be established that the analyzer being verified meets the following requirements:
the analyzer must be presented for verification with a passport (form) and technical description;
The completeness of the analyzer during initial and periodic verification must correspond to the completeness specified in the passport;
Analyzers must be free of the following defects that lead to measurement errors:
malfunction of controls (buttons, switches, handles), connectors, clamps, terminals, fittings, connecting and connecting wires, cables and hydraulic lines, contamination of dials and digital displays;
unclear inscriptions and markings;
damage to the housing and outward-facing structural elements (in particular, the electrodes of submerged primary transducers);
leakage of liquid from internal cavities and flow-through primary converters.

4.2. Testing

4.2.1. When testing the analyzer, the following must be checked:
the ability to install controls and adjustments in any of the provided positions, smooth operation, absence of jamming and reliability of fixation in the installed position;
serviceability of the signaling device for turning on the analyzer to the power supply network and compliance of the rated fuse current with the required value;
the ability to set any indication (output signal value) in all measurement ranges by simulating the analyzed medium or primary transducer;
technical condition of the analyzers according to other parameters provided for in the technical documentation for it.

4.3. Determination of the main error using the complete method

4.3.1. The main error of the analyzer is determined in its entirety by comparing the readings (values ​​of the electrical conductivity or composition corresponding to the measured values ​​of the output signal) of the analyzer being verified with the readings of a standard conductivity meter when checking the analyzer-conductivity meter directly, and when checking the analyzer-concentrator with the composition values ​​determined from the readings of the standard conductivity meter in accordance with normalized relationship between the UEP and the composition of the analyzed liquids.
The main error is determined using calibration solutions that have a specific electrical conductivity corresponding to the measurement range of the analyzer being verified at normal temperature for the liquid being analyzed.

4.3.2. Measurements are carried out sequentially from smaller to larger SEP values. In the case of a fillable primary converter, a sample of the analyzed liquid is taken from the tank in a volume that ensures three times washing and filling of the primary converter of the standard conductometer. The primary transducer filled with the liquid being analyzed is immersed in a glass of distilled water and placed in a tank for thermostatting.
When using a UPS-1 type installation, it is allowed to use a standard conductivity meter with a flow-through design of the primary converter in order to avoid contact with the atmosphere.

4.3.4. The main error is determined at three points corresponding to approximately 20, 50 and 80% of the measurement range (subrange).

4.3.4. The UEP (reading reading) is measured when a stable temperature of the analyzed solution is established in the primary converters of the analyzer being verified and the standard conductivity meter, which is judged by the constancy of the readings for a time sufficient to take the readings (not less than 1 minute and not more than 30 minutes).
When assessing the error, it is allowed not to take into account the results obtained using a standard conductivity meter if they differ from each other by more than 0.3 of the main error of the analyzer being verified. In this case, repeat measurements are carried out until three matching results are obtained within the specified error limits.

4.3.5. The systematic component of the main error according to GOST 13350-78 is determined by the formulas

where is the number of measurements at each point (3),

where is the measured value of the UEP obtained on the analyzer being verified, S/m;
- actual value of electrical conductivity obtained on a standard conductivity meter, S/m;
- normalizing value of the UEP specified in the technical documentation for the analyzer being verified, S/m.
The main error is assessed by the largest of the obtained values, which should not exceed the limits specified in the technical documentation for the analyzer being verified.

4.4. Determination of the main error by element-by-element method

4.4.1. The main error in the UEP range of more than 30 S/m and less than 10 S/m is determined using electrical simulators element by element: the main error of the analyzer measuring unit and the constant of the primary transducer are determined.

4.4.2. The constant of the primary converter is determined at least three times in one of the measurement ranges (subranges) according to the tables of reference Appendix 4.

4.4.2.1. The value of the electrical conductivity of the selected solution is determined using a standard conductivity meter after thermal equilibrium has been established. At the same time, the reading of the measuring unit of the analyzer is recorded.

4.4.2.2. The primary transducer of the analyzer is replaced with a resistance store and by selecting the resistance on it, the readings of the measuring unit of the analyzer are obtained that correspond to the readings obtained from the solution.

4.4.2.3. The analyzer primary converter constant is determined by the formula

where is the SEP value according to a standard conductivity meter, S/m;
- value of simulating resistance, Ohm.
The arithmetic mean of the results of three measurements is taken as the constant of the sensitive element of the analyzer,

4.4.2.4. The error in determining the constant of the analyzer primary converter is estimated using the formula

where * is the value of the primary converter constant, calculated using formula 3, m.
* - value of the constant according to the technical documentation for the analyzer, m.
________________

The error in determining the constant of the primary converter should not exceed the value specified in the technical documentation.

4.4.3. The main error of the analyzer measuring unit is determined by replacing the primary transducer with a simulating resistance at three points, corresponding to approximately 20, 50 and 80% of each range (subrange).

4.4.3.1. The value of simulating resistances for each of the points being tested is determined by the formula

where is the UEP value corresponding to each checked point on the scale, S/m;
* - constant of the primary converter, determined according to the method of clause 4.4.2.3, m.
________________
* The formula and its explanation correspond to the original. - Note.

4.4.3.2. The systematic component of the main error is determined by formulas (1) and (6)

where is the UEP value on the analyzer scale corresponding to the point being tested, S/m;
- measured value of the electrical resistivity corresponding to the simulating resistance, S/m.

4.4.3.3. It is allowed to determine the main error by the element-by-element method according to the methodology set out in clause 4.4 and in other ranges of the electrical power, as well as in justified cases using a method that differs from that set out in clause 4.4.

4.5. Determination of changes in readings (output signals) depending on changes in the temperature of the analyzed liquid

4.5.1. The change in readings (output signals) from changes in the temperature of the analyzed medium is determined using working solutions at three points of each range (subrange) specified in clause 4.3.3, when the temperature of the analyzed medium changes by ±15 °C from the working temperature value.

4.5.2. Changes in readings (output signals) depending on changes in the temperature of the analyzed liquid are determined by the formula

where is the value of the electrical conductivity at operating temperature, S/m;
- UEP value at a temperature different from the operating temperature by ±15 °C.

4.5.3. The change in the analyzer readings due to a change in the temperature of the analyzed medium by ±15 °C from the operating temperature should not exceed the permissible value of the basic error of the analyzer being verified.

4.6. The verification results are recorded in the verification protocol given in the mandatory Appendix 1.

5. REGISTRATION OF VERIFICATION RESULTS

5.1. The manufacturer formalizes the positive results of the initial verification of the analyzers with an entry in the passport, certified by the verifier, with an imprint of the verification stamp.

5.2. Positive results of periodic verification of analyzers carried out by the state metrological service are formalized by branding and the issuance of a certificate in the form established by Gosstandart.

5.3. Positive results of periodic verification of analyzers carried out by the departmental metrological service are documented in the manner established by the departmental metrological service.

5.4. Analyzers that have passed verification with a negative result are not allowed to be released into circulation or for further use: the marks on them are canceled and a notice of unsuitability is issued. The verification certificate will be cancelled.

APPENDIX 1 (mandatory). FORM OF VERIFICATION PROTOCOL

ANNEX 1
Mandatory

PROTOCOL N

MEANS OF VERIFICATION APPLIED

CONDITIONS OF VERIFICATION:

VERIFICATION RESULTS

b) by electrical simulators

4. Determination of changes in readings (output signals) from changes in the temperature of the analyzed medium

APPENDIX 2 (for reference). DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTION OF OPERATION OF THE UPKK-2 TYPE INSTALLATION

APPENDIX 2
Information

1 - pump; 2 - tank of flow primary converters; 3 - fridge; 4 - submersible tank
primary converters; 5 - flow primary converter; 6-8 - three-way valves;
9 - resistance thermometer; 10 - thermostat; 11 - coil

Installation specifications

The working medium is aqueous solutions of sodium or potassium chloride.

The range of UEP of solutions circulating in the system is 1·10-100* S/m.
________________
* Corresponds to the original. - Note.
Temperature instability of the working environment is ±0.2 °C.


Power supply from AC mains voltage 220 V%, frequency (50±1) Hz.

Description of the installation

Flow primary converter 5 installed on flanges selected depending on their diameter from the set of installation accessories. The submersible primary converter is placed in the tank of submersible primary converters 4.
The hydraulic system of the installation is filled with a solution of potassium chloride or sodium through a tank 2 or 4 . The required concentration of the solution is achieved by dissolving the required amount of salt in distilled water (see reference Appendix 4), recalculated for the working volume of the analyzed medium.
Turning on the pump 1 ensure circulation of the solution in the system.
Depending on the set temperature regime, the thermostat is turned on 10 or refrigerator 3 and set the temperature corresponding to the one selected from Table 1 or 2 of Reference Appendix 4.
The temperature of the solution is controlled using an electronic bridge complete with a resistance thermometer 9 .
After establishing the set temperature, adjust the concentration by adding to the tank 2 or 4 water or a more concentrated salt solution until the analyzer readings coincide with the digitized point. The concentration is measured gradually until the temperature and concentration are equalized. At other points being checked, verification is carried out as described above.

APPENDIX 3 (for reference). DIAGRAM, TECHNICAL CHARACTERISTICS AND DESCRIPTION OF OPERATION OF THE UPS-1 TYPE INSTALLATION

APPENDIX 3
Information

1-4 - tanks; 5-6 - pumps; 7 - ion exchange columns; 8 - tap for sampling the solution; 9 - verified
primary converter; 10, 13, 15, 18, 19, 20, 22 - valves; 11 - thermostat;
12 - resistance thermometer; 14, 16, 17 - funnels for filling; 21, 23 - funnels with soda lime

1. Technical characteristics of the installation

Working medium - distilled water, aqueous solutions of sodium chloride.
The range of UEP of solutions circulating in the system is 1·10-1·10 S/m (in units of conventional concentration of sodium chloride - 0-1000 mg/l).
The temperature range of the working environment is 5-80 °C.
Temperature instability of the working environment ±0.2 °C.
The time to establish stable concentration readings from the analyzer being verified is 30 minutes.
The time to establish a stable temperature of the working environment is 30 minutes.
Power supply from AC mains voltage 220 V%, frequency (50±1) Hz.
Power consumption - no more than 2 kW.

2. Description of the installation

The analyzer is turned on and warmed up for 20 minutes.
Fill the tank with distilled water 1 and open the valves 15 And 19 ion exchange column 7 . After filling the tank 2 close the valve 19 , open the valve 13 , turn on the pump and fill the tank 3 . Pump 5 turn off.
Tank 4 filled with a sodium chloride solution with a concentration an order of magnitude higher than the concentration of the range being verified (see Table 1 or 2 of Reference Appendix 4). Turn on the pump 6 , ensuring circulation of the solution in a closed system.
Turn on the thermostat 11 and using the temperature setter of the electronic bridge, set the temperature corresponding to the operating temperature of the analyzer being verified.
Then change the concentration by adding water or salt solution and adjust the valves 22 or 18 until the analyzer readings coincide with the digitized point being tested. The concentration is changed gradually until the temperature and concentration are equalized.
At the remaining points being checked, the test is carried out as described above.
To take a sample of the solution on a standard device, use tap 8.

APPENDIX 4 (for reference). DEPENDENCE OF SPECIFIC ELECTRICAL CONDUCTIVITY OF SODIUM AND POTASSIUM CHLORIDE SOLUTIONS ON CONCENTRATION AND TEMPERATURE

APPENDIX 4
Information

Table 1

table 2