Brooks Instrument 5851EM - Manual (Page 40)

4-2
Brooks ® Models 5965, 5851EM
Section 4 Maintenance
& Troubleshooting Installation and Operation Manual
X-TMF-5965-5851EM-MFC-eng
Part Number: 541B122AAG
September, 2009
No routine maintenance is required on the Models 5965 and 5851EM. If an
in-line filter is used, the filtering element should periodically be replaced.
4-2 Troubleshooting
It is important that this controller only be serviced by properly
trained and qualified personnel.
CAUTION
A. System Checks
The Models 5965 and 5851EM are 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 3-5 through 3-9.
If it becomes necessary to remove the controller from the system
after exposure to toxic, pyrophoric, flammable or corrosive gas,
purge the controller thoroughly with a dry inert gas such as
Nitrogen before disconnecting the gas connections. Failure to
correctly purge the controller could result in fire, explosion or
death. Corrosion or contamination of the mass flow controller,
upon exposure to air, may also occur.
WARNING