3 technical assistance – Dwyer GFM User Manual
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20
INDICATION
GFM is disconnected from
the source of the gas (no
flow conditions) but LCD
Display reading is
fluctuating in wide range.
Output voltage 0-5 Vdc
signal also fluctuating. The
power supply voltage is 12
Vdc and stable.
Reading on the LCD Display
ten (hundreds) times less
or more than actual gas
flow. Output voltage
0-5 Vdc signal corresponds
correct gas flow.
REMEDY
Return GFM to factory for
repair.
Carefully remove the LCD
from GFM. Remove the
aluminum housing on the
side of the connection cable.
Side the LCD assembly out
of the aluminum housing.
Reinstall jumper to the
appropriate location on the
8-pin header block
(see 7.4.3 on page 15).
LIKELY REASON
Sensor or PC board is
defective.
Decimal point jumper is
installed in wrong position
on the LCD Display Circuit.
For best results it is recommended that instruments are returned to the factory
for servicing. See section 1.3 for return procedures.
8.3
Technical Assistance
Dwyer Instruments will provide technical assistance over the phone to qualified
repair personnel. Please call our Technical Assistance at (219)-879-8000. Please
have your Serial Number and Model Number ready when you call.