4-1
Brooks
®
Model 5850i
Section 4 Maintenance
Installation and Operation Manual
X-TMF-5850i-MFC-eng
Part Number: 541B108AAG
November, 2008
4-1 General
No routine maintenance is required on the Model 5850
i
other than an
occasional cleaning. If an in-line filter is used, the filtering element should
periodically be replaced or ultrasonically cleaned.
4-2 Troubleshooting
A. System Checks
The 5850
i
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 low resistance power supply connections and that the correct
power supply voltage and signals are reaching and leaving the
controller. The breakout board (P/N S-273-Z-668-AAA) listed in
Section 5 will make this job much easier.
2. Verify that the process gas connections have been correctly termi-
nated and leak checked.
3. If the mass flow controller appears to be functioning but cannot
achieve setpoint, 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 Figure 3-5.
B. Bench Troubleshooting
1. Properly connect the mass flow controller to a +15-28 Vdc power
supply, setpoint source and connect an output signal readout device
(4-1/2 digit voltmeter recommended) to pins 2 and 10 of the D-
connector (refer to Figure 2-2). Apply power, set the setpoint to zero
and allow the controller to warm up for 45 minutes. Do not connect
to a gas source at this time. Observe the output signal and, if
necessary, perform the zero adjustment procedure (Section 3-3). If
