4-3
Brooks
®
Model 5860
i
Section 4 Maintenance
Installation and Operation Manual
X-TMF-5860i-MFM-eng
Part Number: 541B110AAG
November, 2008
voltmeter recommended) pins 2 and 10 (Refer to Figure 2-2). Apply
power, and allow the flowmeter 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
the output signal will not zero properly, refer to the sensor
troubleshooting section and check the sensor. If the sensor is
electrically functional, the printed circuit board is defective and will
require replacement.
2. Connect the flowmeter to a source of the gas on which it was
originally calibrated. Increase the flow until 100% indication
(5.00Vdc) is achieved. Vary the flow rate over the 2 to 100% range
and verify that the output signal follows the flow rate. If possible,
connect a flow measurement device in series with the mass
flowmeter to observe the actual flow behavior and verify the
accuracy of the mass flowmeter. If the mass flowmeter functions as
described above, it is functioning properly and the problem may lie
elsewhere.
Table 4-1 lists possible malfunctions which may be encountered during
bench troubleshooting.
C. Sensor Troubleshooting
If it is believed the sensor coils are either open or shorted, troubleshoot
using Table 4-2. If any of the steps do not produce the expected results the
sensor assembly is defective and must be replaced. Refer to Section 4-4
for the disassembly and assembly procedures to use when replacing the
sensor.
Note: Do not attempt to disassemble the sensor.
D. Cleaning Procedures
Should the Model 5860
i
Mass Flow Meter require cleaning due to
deposition, use the following procedures:
1. Remove the unit from the system.
2. Refer to Section 4-4 to disassemble the meter.
3. Use a hemostat or tweezers to push a 0.007" dia. piano wire through
the flow sensor tube to remove any contamination. For best results
push the wire into the downstream opening of the sensor tube. The
sensor tube can be flushed with a non-residuous solvent (Freon TF
®
recommended). A hypodermic needle filled with solvent is a
convenient means to accomplish this.
