BRONKHORST EL-FLOW Select Series, Instruction Manual

Page: 49 / 53

Bronkhorst®
Instruction Manual EL-FLOW® Select 9.17.099J 49
5.3 Common issues
Symptom Possible cause Action
No (fieldbus) communication No power supply ·
Check power supply
·
Check cable connection
·
Check cable hook-up
Invalid node address Change node address (see Network
configuration )
Other Reset instrument and/or restart master. If
problem persists, contact Bronkhorst.
No output signal No power supply ·
Check power supply
·
Check cable connection
·
Check cable hook-up
Invalid control mode (instrument
accepts no setpoint)
Check control mode (see Special parameters )
No setpoint given or setpoint too
low
Give setpoint 2%
Control valve in Safe State
(normally closed)
Check if control valve is in safe state; solve
cause if necessary (see Valve Safe State )
Inlet pressure or differential
pressure too low
Increase inlet pressure
Piping, filters and/or control valve
clogged or blocked
·
Flush fluid 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 (see
section Piping requirements )
Inlet and/or outlet pressure too
high or too low
Adjust pressure and/or set instrument pressure
in accordance with actual process pressure (e.g.
with FlowTune™)
Wrong process gas selected Select correct process gas (e.g. with FlowTune™)
Wrong controller settings Adjust settings (e.g. with FlowPlot)
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.:
·
fluid lines
·
valves
· filters
Setpoint too low Give setpoint 2%
Inlet pressure or differential
pressure out of bounds
Set inlet pressure to a value within
specifications