Brooks MFM - Table 4-1: Bench Troubleshooting

Installation and Operation Manual
X-TMF-MfS-MFC-eng
PN 541-C-061-AAG
November, 2008
MF Smart Series
23
Table 4-1: Bench Troubleshooting
Trouble Possible Cause Check/Corrective Action
Output stays at zero (regardless of Clogged Sensor Clean sensor. Refer (Section 4.3).
Set point) and there is ow through
the meter/controller Defective electronic board
Flow can not be achieved regardless Clogged Control Valve Clean the control valve (section 4.3) or
of checkpoint. (applicabable to MFC) return the device to the factory
Valve override input is grounded Check the valve override input
(pin 5 of 9 row)
Defective electronic board Contact Brooks Instrument.
Output signal stays at approx. 5.25 Valve leaks or is stuck open Clean and/or adjust control valve
Vdc or 21 mA (regardless of Set (applicable to MFC) (Section 4.3).
point) and there is ow through the
meter/controller +15V applied to the valve override Check the valve override terminal
input (applicable to MFC) (pin 5 of 9 row)
Defective electronic board Contact Brooks Instrument.
Output signal follows Set point at Control valve leaks or is stuck open Clean the control valve or return the
higher set points but will not go device to the factory (Section 4.3)
below 2%
Output signal follows Set point at Insufcient inlet pressure or pressure Adjust pressures, inspect in-line lters
lower set points, but does not reach drop and clean/replace as necessary 4.2
full scale
Partially clogged sensor Clean sensor, see cleaning procedures
(Section 4.3)
Partially clogged valve Clean the control valve (section 4.3) or
(applicable to MFC) return the device to the factory, see
cleaning procedures
Valve out of adjustment Adjust valve, see calibration procedures
(applicable to MFC) (Section 4.4)
Valve guide spring failure Controller oscillates (see below)
(applicable to MFC)
Instrument grossly out of calibration. Partially clogged sensor Clean sensor, see cleaning procedures
Flow is higher than desired (Section 4.3)
Instrument grossly out of calibration. Partially clogged restrictor Replace or clean restrictor.
Flow is lower than desired
Controller oscillates Pressure drop or inlet pressure Adjust pressures
(applicable to MFC) deviates from calibrated values
Oversized orice Check orice size.
Valve out of adjustment Adjust valve, see calibration procedures
(section 4.4)
Unstable inlet pressure Check external pressure regulator
Defective p.c. Board Contact Brooks Instrument
Section 4: Maintenance