Section 4 Maintenance & Troubleshooting
Tables 4-1 and 4-2 list possible malfunctions which may be encountered dur-
ing bench troubleshooting.
For Analog Controller Models Only
: Apply +5 Vdc to the valve override pin
(pin 12) and verify that the output exceeds 100%. Connect the valve override
pin to the power supply common (pin 9) and verify that the output signal falls
below 2%.
Cleaning Procedures
When deposition makes it necessary to clean the Brooks SLAMf Digital Series
Mass Flow Controller or Mass Flow Meter, use the following procedures:
1. Remove the unit from the system.
2. Purge with dry nitrogen gas, which removes virtually all particulate mat-
ter from the device. Should contamination persist, subject all wetted
1
components to ultrasonic cleaning. Following this, purge the device
thoroughly with dry nitrogen gas once again.
3. If the sensor is contaminated, remove the sensor and use a hemostat
or tweezers to push a 0.007" diameter piano wire through the
flow-sensor tube to remove any contamination (end closest to the
control valve). The sensor tube can then be flushed with a solvent that
leaves no residue. This can be accomplished conveniently using a
hypodermic needle filled with solvent.
NOTE: Do not soak the sensor assembly in a cleaning solvent. If solvent
seeps into the sensor assembly, it will likely damage or significantly alter the
sensor's operating characteristics.
Figure 4-1 Bench Troubleshooting Circuit
1
Wetted components include the body, laminar-flow element, and all valve components including the orifice, process adapters and inlet filters
(if so equipped).
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