QmB Series IP40, IP65, IP65XP
Section 4 Maintenance
4-4
Installation and Operation Manual
X-CM-QmB-eng
Part Number: 541B029AHG
June, 2008
control you can replace or
disassemble and clean the valve.
(See Section 4-3)
Particulates in the flow stream.
Use an inlet filter.
Agglomeration of fluid at orifice.
Consider a larger orifice (valve
stability could suffer).
Chemical deposits.
Institute regular PM back flushing.
Poor filtration of process fluid.
Install proper filtration.
Valve out of adjustment
Contact Brooks Instrument.
(applicable to Controller).
Valve out of adjustment
Valve guide spring failure
Contact Brooks Instrument.
(applicable to Controller).
Valve override input is grounded
Check the valve override input
(Pin12).
Defective electronic board
Contact Brooks Instrument.
Output signal follows Setpoint
Control valve leaks or is stuck
Exercise the control valve
at higher Setpoints but will not
open.
alternating between valve override
go below 2%
"open" and closed. If problem
persists backflush the device with
a solvent or purge gas with valve
override "open".
Output signal stays in approx.
Valve leaks or is stuck open
Backflush the device with
5.5 Vdc or 22 mA
(applicable to Controller).
a solvent or purge gas with valve
(regardless of setpoint) and
override "open".
there is flow trough the
meter/controller
+15 Vdc applied to the valve
Check the valve override terminal
overrride input
(Pin 12).
(applicable to Controller).
Defective PC board.
Contact Brooks Instrument.
Observation
Cause
Resolution
Table 4-1 Troubleshooting (continued)
