Bronkhorst RS232 interface - Manual (Page 30)

BRONKHORST ®
Page 30 RS232 interface 9.17.027
6 TROUBLESHOOTING
6.1 LED
INDICATIONS
LED indications can be very useful in case of problems with the instrument.
The green LED is normally used for instrument status indication, like normal operation or special function mode. For
DeviceNet it is also possible to show that the instrument is in abort state and idle state. The red LED is normally used
to for error/warning indication (how longer the flash, how greater the trouble).
More information can be found in the manual “917023 Operational instructions digital instruments”
This document can be found at:
http://www.bronkhorst.com/en/downloads/instruction_manuals/
6.2 T ROUBLESHOOTING HINTS AND TIPS
SITUATION Description
RS232 communication problems Check cables. Make sure correct cables are used for specific purpose.
Check address of interface (slave). Sending messages to node 128 will mostly
be accepted by the interface.
Try to reset the instrument and/or restart your PC/PLC.
Make sure your messages are assembled according to FLOW‐BUS protocol
description.
Make sure the parameter values you try to read/write are available and in
the correct ranges (check tables).
Controller doesn’t respond on setpoints:
 Check control mode, when 0 and other field bus gives error: safe state
will be entered, resulting in safe setpoint. Can be overruled by making
control mode = 18 (RS232 only operation)
 Alarm or counter module in instrument forces setpoint to alarm setpoint.
Reset alarm or counter and proceed.
 Setpoint slope could have very high value. New setpoints will be reached
when this slope time has been elapsed. Make setpoint slope smaller.
 Control mode could have other value than 0 or 18. Check function when
value is different.
 If measure doesn’t change check forward pressure and piping (evt. shut‐
off valves).
 Make sure setpoints are within allowed range: 0...32000 (= 0...100%).
 Make sure setpoints are send to proper instrument and process (mostly =
1) and parameter (FBnr for setpoint = 1), and type of data is correct
(short integer = 2 bytes MSB first)
Other (FLOW‐BUS) problems Contact Bronkhorst local sales representative or send e‐mail describing your
problem to: see service chapter.