Troubleshooting - BRONKHORST FLOW-BUS Instruction Manual

TROUBLESHOOTING

Symptom
No output signal on FLOW-BUS
interface
No or slow response to setpoint
changes
Inaccuracy of measurement
Analog output range is too low/high
No/bad connection to FLOW-BUS
No communication possible with PC-
software program
Red or green LED's are blinking on
top of the instrument
No/bad reaction to manual
instructions by means of micro push-
button switch on top
Master-slave controlling doesn't
function well
Controller doesn't function as wanted
Other troubles
9.17.024
BRONKHORST HIGH-TECH B.V.
Possible cause
Bad communication with FLOW-BUS
Slope value could be set too high
(ramp function for setpoint signal)
Control mode/setpoint source for
instrument could point to a different
setpoint source
Other instrument (or PC) connected
to FLOW-BUS could change the
setpoint
Polynomial factors could be wrong
Wrong fluid (and thus calibration
settings) could be selected (up to 8
fluids possible)
Wrong output range could be selected
Wrong cable used
Bad termination of RS485 bus-line
Other module(s) on the bus could
cause trouble
Interface settings could be wrong
Interface has bad connection to
FLOW-BUS
Instrument is in a special operation
mode or is indicating some kind of
error/warning
Some actions can only be used under
special conditions
Connection to master signal could be
lost
Settings for this special controlling
mode could be wrong
Settings for controller are for other
behaviour than you want
One or more parameter settings could
be wrong
Action
Check communication e.g. with
local readout module or PC-test
program
Check and/or change slope value
with readout module or PC-software
program
Check if correct control
mode/setpoint source is selected for
the instrument
Make sure who is in charge to
change setpoints
Check if right fluid has been
selected and check polynomial
factors A..D with those on your
calibration certificate
Check if correct fluid is selected for
this instrument
Check if powering of instrument is
done correctly
Check if wanted output range
(analog) is selected
Check cabling
Check bus termination
Check correct functioning from other
module(s) on the bus (PC-programs
with interface modules included)
Check settings e.g. for RS232
(COM-port and baudrate)
Check cabling of interface
See manual 9.17.023 for more
details
See manual 9.17.023 for more
details
Check if master output is given
correctly
Check if settings are correct (control
mode, slave-factor)
Under certain conditions you could
run an auto-tune for controller
optimisation.
(see manual 9.17.023)
Change reponse factor settings for
controller (see manual of
readout/control module or
PC-software)
Get back original factory settings by
means of micro push-button on top
(see manual 9.17.023)
Contact sales representative for
assistance if the above doesn't help
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