Brooks Instrument 5850E - Manual (Page 34)

4-2
Installation and Operation Manual
X-TMF-5850E-MFC-eng
Part Number: 541B102AAG
September, 2009
Section 4 Maitenance &
Troubleshooting
Brooks ® Model 5850E
4-2 Troubleshooting
A. System Checks
The Model 5850E is generally used as a component in gas handling
systems which can be quite complex. This can make the task of isolating a
malfunction in the system a difficult one. An incorrectly diagnosed
malfunction can cause many hours of unnecessary downtime. If possible,
make the following system checks before removing a suspected defective
mass flow controller for bench troubleshooting or return, especially if the
system is new.
1. Verify a low resistance common connection, correct power supply
voltage and that signals are reaching and leaving the controller. The
breakout board, P/N S273Z649AAA - Card Edge version or P/N
S273Z668AAA - D-Connector version listed in Section 5, will make this
job much easier.
2. Verify that the process gas connections have been correctly terminated
and leak-checked.
3. If the mass flow controller appears to be functioning but cannot achieve
set-point, verify that sufficient inlet pressure and pressure drop are
available at the controller to provide the required flow.
4. Verify that all user selectable jumpers are in their desired positions
(refer to Figures 3-3 and 3-4).
B. Bench Troubleshooting
1. Properly connect the mass flow controller to a ±15 Vdc power supply
command voltage source and connect an output signal readout device
(4-1/2 digit voltmeter recommended) to Terminals 2 and 3 or D-Connec-
tor Pins 2 and 10 (refer to Figures 2-2 and 2-3). Apply power, set the
command voltage to zero and allow the controller to warm-up for 45
minutes. Do not connect to a gas source at this time.