Bronkhorst®
Instruction Manual EL-FLOW® Classic series
9.17.085D
15
5
Troubleshooting and service
For a correct analysis of the proper operation of a flow meter/controller it is recommended to remove the unit from the
process line and check it without applying fluid supply pressure. In case the unit is dirty, this can be ascertained
immediately by loosening the compression type couplings on the inlet side.
Energizing and de-energizing the instrument can indicate if there is an electronic failure. After energizing, control behavior
can be checked by applying fluid pressure.
If you suspect leakage, do not check for gas bubbles with a leak detection liquid under the cover, as this may short-circuit
the sensor or the printed circuit board.
Do not disassemble the instrument for inspection, but contact your local distributor for service or repairs.
5.1
Errors
See
LED indications
for an explanation of the LED indications the instrument can give.
5.2
Common issues
Symptom
Possible cause
Action
No output signal
No power supply
·
Check power supply
·
Check cable connection
·
Check cable hook-up
No setpoint given or setpoint too
low
Inlet pressure or differential
pressure too low
Increase inlet pressure
Piping, filters and/or control valve
clogged or blocked
·
Flush fluidic system with clean, dry air. If
problem persists, contact Bronkhorst.
·
For external proportional control valves:
supply 0…15 Vdc and operational inlet
pressure to valve and slowly increase
voltage. If valve does not open, clean parts
and re-adjust valve
Laminar flow element clogged or
blocked
Return equipment to factory
Sensor failure
Return equipment to factory
Control behavior unstable
Measurement disturbed by
vibrations
If possible, avoid installation in close proximity
of mechanical vibration
Inlet pressure unstable
Install pressure regulator or increase buffer
volume between controlling instruments
Inlet and/or outlet pressure too
high or too low
Adjust pressure and/or set instrument pressure
in accordance with actual process pressure
Wrong process fluid supplied
Supply instrument with fluid it was configured
for
Control valve damaged
Return equipment to factory
No flow (sending a setpoint has no
effect)
No fluid supply
Check upstream components for obstruction,
e.g.:
·
fluidic lines
·
valves
·
filters
Setpoint too low
