Naris
Naris
User’s
Manual V14 14/02/20 Page 43 of 52
SERVICING
Servicing can only be carried out by GMI approved and
authorised personnel. No modifications are allowed
.
The NR6 contains two transducers with associated instrumentation amplifiers, balance and
gain controls, and an is5 Volts to +8V DC converter. Full circuit diagrams are available
on request and service adjustments are noted below.
TRANSDUCER SETUP ADJUSTMENTS
1. Switch on the NR6 and allow 5 minutes to warm up.
2. Measure the voltage between test point 5 and test point 4 using a sensitive DC voltmeter.
Adjust pressure offset potentiometer VR
4
to give a reading of 0 volts.
3. Measure the voltage between test point 5 and test point 6 using a sensitive DC voltmeter.
Adjust flow offset potentiometer VR
1
to give a reading of 0 volts.
TRANSDUCER CALIBRATION ADJUSTMENTS
1. Pressure Channel - the gain of the pressure transducer is adjusted by means of calibration
potentiometer, VR
5.
2. Flow Channel - the gain of the flow transducers is adjusted by means of calibration
potentiometer, VR
2
.