Answer / ejaz maqsood

Because the Bentlay Nevada uses the NPN Transister. thats why its suplly in negtive voltage

Answer / carl_ellis

Because negative voltage is what the Bentley Nevada circuits use.

The regional guy from Bentley Nevada was in the other day so I asked him. His answer, "Historical legacy. It's always been that."

The point is, if the circuits need a negative voltage, that's what's used.

Carl Ellis
Measure First

Answer / mohammad javed

Don Bentley uses the PNP transistor which works on negative bias voltage. That why a negative voltage is used in vibration sensors. It is the circuit design which require negative voltage.

why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of DCS then why we use DCS.

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i need some objective type questions in instrumentation

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what is dead weight tester and where it is used?.

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