Brooks Instrument SLA5810/20 - Manual (Page 28)

4-2
Installation and Operation Manual
X-PR-SLA5800-PC-eng
Part Number: 541B091AAG
July, 2010
Models SLA5810 and SLA5820
Section 4 Maintenance & Troubleshooting
Figure 4-1 Bench Troubleshooting Circuit
A. System Checks
The SLA5800 pressure controller 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 down time.
If possible, make the following system checks before removing a
suspected defective pressure controller for bench troubleshooting or return
to the factory, especially if the system is new.
1. Verify a low resistance common connection and that the correct power
supply voltage and signals are reaching and leaving the controller. The
Break-out Board (P/N S273Z649AAA) will make this job much easier.
2. Connections may not be secure. Check all cable connections.
3. If the pressure 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.
B. Problem: signal doesn’t reach setpoint.
Failure of the pressure signal to achieve the setpoint could be caused by a
number of factors:
1. Insufficient pressure in system (low or no pressure).
2. Valve Override pin is active. If the valve override pin is active, the valve
will be forced open or closed. Set this pin to its normal level before
setting a setpoint.