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With the examination and measuring of gas meters with
impulse exits the program under test and a normal counter with a
continuous defined flow rate are subjected. The impulses delivered by
the counters are counted and, after the evaluation, compared together with the impulse priority corresponding in each
case. The deviation
of the results of the count enables a statement about the accuracy of
the program under test. Two channels are combined into a logical
group in each case, i.e. the differences between channel 1 and 2 or
channel 3 and 4 are determined additionally, and the exceeding of a
freely selectable maximum difference is displayed online. This
permanent channel comparison 1<=>2 and 3<=>4 is
active in all 3 modes described in the following part.
The electronic registration of the counting impulses
is to be carried out in
3 different modes:
Mode 1 - manual registration
Counting the incoming impulses of the attached
givers is
started and terminated manually by operating the start / stop key.
In addition all 4 counter channels are started and stopped at the same time .
Mode 2 - base-controlled
Counting the incoming impulses of the attached
givers is
started manually by operating the start / stop key and stopped
automatically after the input of a preset number of impulses on one of
the 4 channels. The number of impulses and the stopping, so-called
base channel are freely selectable.
Mode 3 - time-controlled
This mode serves to directly determine
the flow in m3/h. All incoming impulses are
registered by a freely definable gate time and standardized by a functional connection to a value per
hour. The different constants of the gas meters enter
the mathematical
measured value calculation by freely definable, so-called impulse values K1 to K4 .
A scanner integrated in the device enables
a fast evaluation of the quality of the
even registered impulses by a diagram of the function courses of one or several channels concerning the position of
the trigger thresholds. For the implementation of this measuring function, the available universal impulse counter for gas measuring
instruments was developed in direct coordination with the user, the
weights and measures office Fürstenwalde.
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