Fluke RUSKA 2413, Руководство пользователя

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RUSKA 2413, 2417 & 2416
Users Manual
2-2
Whenever a liquid is used in either side of the transducer, an open tube manometer must
be connected in such a way that the pressure across the diaphragm may be adjusted to
zero and that the meter may also be adjusted to indicate zero. In a liquid-to-liquid system,
two manometers must be used — one in each of the liquid systems. Manometers suitable
for this purpose are available.
A special application of the differential pressure null indicator is one in which the unit is
used when cross-floating two dead-weight gages. A by-pass valve arrangement is
provided for the purpose of directly connecting the two gags while making preliminary
balancing adjustments. When the two gages are at pressure and approximately balanced,
the valve is opened and the electrical zero adjusted. The valve is then closed and the
balancing operation continued, while observing the residual pressure difference on the
meter. As the pressures become more nearly equal, the valve is opened to verify the
correct zero adjustment and then closed and opened alternately until no difference in
meter readings is observed when the valve is either open or closed. The resolution of the
entire system is quickly determined by placing a small weight on one gage and observing
the effect on the meter. When using the transducer for this purpose, calibration of the null
shift with working pressure is unnecessary.