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2) The means of verification prepared for working according to the operational
documentation.
9.5. Verification realization
9.5.1. External survey
External survey of the verificated RMT should be done according to article 7.1 of the present
passport.
9.5.2. Approbation should be carried out by connecting the RMT with the measuring circuit
according to article 9.5.3, and the following must be checked:
1) conformity of the RMT indications to zero value by measured quantity and by the record
of measured quantity;
2) conformity of the RMT indications to the value of the input source signal conforming to
the lower value limit by the record of measured quantity (for RMTs, which have different ranges of
measured quantity and of the record of measured quantity).
9.5.3. Definition of the values of the basic indicated errors of measured quantities of RMT
9.5.3.1. The basic indicated error of measured quantities of the measuring channels intended
for working with thermal converters of resistance TC and thermoelectric converters of resistance
ТП, and also with input source electric signals in form of direct current voltage is determined in
points conforming to 5, 25, 50, 75, 95 % of the ranges of measurements, for what:
1) the measuring channel of the verified RMT is connected to the shop of resistance or to the
comparator of voltage by means of scaling cable (for measuring channels designed for working with
thermal converters of resistance or thermoelectric converters of resistance accordingly);
2) resistance values or т.э.д.с., conformed to the verified point of the measuring channel are
installed consistently in the shop of resistance or in the comparator of voltage;
3) the nominal static characteristics NSC of the thermal converters of resistance and
thermoelectric converters of resistance should conform to STATE STANDARTS 6651-94 and
STATE STANDARTS Р 50431-92 accordingly;
4) the difference between the indications of the RMT measuring channel and the real value
of temperature in the verified point manifested in the percentage of measurements range should not
exceed the appropriate value fixed in article 3.4 and the table 1 of the present passport;
5) the measuring channel is connected to the input source electrical signal in form of voltage
of direct current with the source of calibrated voltages;
6) with the help of the latter the input signal value is set in the verified point;
7) the difference of the indications between the verified measuring channel and the real
value of the measured quantities determined on the calibrating curve, should not exceed the values
calculated by the formula (9.1)
⎮А
изм
– А
д
⎮
,
100
2,0)(
R
АА
нв
+
⋅−
≤
(9.1)
Where
н
А
- lower limit rate of measurements;
в
А
- top limit of measurements;
Аизм - measured value of quantity in the verified point;
Hell – real value of quantity in the verified point;
R - one unit of the last mark;
0,2 - admitted basic indicated error of the measured quantity.
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