Fluke MOLBOX RFM Operation And Maintenance Manual page 163

SYMPTOM
Flow rate is changing but display of flow is
not and the bottom right hand corner of the
display is a numerical countdown followed
by <avg>.
Current flow through molbloc-L is zero but
reading is not zero.
Poor flow measurement characterized by
instability and sudden small jumps in flow
rate.
Grossly inaccurate flow measurements
and little or no response to pressure or
flow changes.
Apparent inaccurate pressure
measurement.
Apparent inaccurate pressure or flow
measurement.
Table 25. Troubleshooting Checklist (Continued)
PROBABLE CAUSE
AVERAGE DISPLAY function is
ON and pressure
updating only with the average
value at the end of each averaging
cycle.
Need to run TARE function to zero
molbox RFM RPTs.
The molbox RFM pneumatic circuit
is contaminated with liquids.
RPT(s) destroyed by overpressure.
Incorrect pressure units.
Reference pressure
(RPT) calibration coefficients have
been altered or lost and pressure
measurements are incorrect.
Page 153
SOLUTION
Go to a DISPLAY function other than
display is AVERAGE or press [+/-] to get the
instantaneous value AVERAGE DISPLAY.
(3.4.6.2)
Run TARE. (3.4.4.1)
Purge and clean
associated pneumatic systems.
your DHI Authorized Service Provider.
View pressure readings using [P&T].
readings are grossly inaccurate and don't
respond to pressure changes, contact your
DHI Authorized Service Provider.
3.1.6.2, 3.6.7)
Set desired pressure units.
reference temperature if unit is inWa.
(3.5.2)
transducer Check and correct calibration coefficients if
needed. (5.2)
© 1998-2007 DH Instruments, a Fluke Company
6. TROUBLESHOOTING
molbox RFM and
Contact
If
(3.4.5,
Consider