Section 4 Maintenance & Troubleshooting
Remove the sensor connector from the PC Board for this procedure.
OHMMETER CONNECTION
RESULT IF ELECTRICALLY FUNCTIONAL
Open circuit on ohmmeter. If either heater (1) or
Pin 1 or 4 to meter body
sensor common (4) are shorted, an ohmmeter
reading will be obtained.
Pin 4 to Pin 2
Nominal 1100 ohms reading, depending on
Pin 4 to Pin 3
Pin 5 to Pin 1
Nominal 1000 ohm reading.
Pin 6 to Pin 7
Nominal 580 ohm reading.
temperature and ohmmeter current.
SENSOR
SCHEMATIC
PIN
NO. FUNCTION
1
Heater
Upstream
2 Temperature
Sensor (Su)
Downstream
3 Temperature
Sensor (Sd)
4
Sensor Common
5
Heater Common
6 Thermistor
7 Thermistor
Table 4-2 Sensor Troubleshooting
Calibration Procedure
The calibration of Brooks Digital Series Mass Flow devices is not described
in this manual. Such calibration requires accurate and traceable calibration
equipment in addition to digital communications.
If your device needs calibration Brooks Instrument can provide this service
at one of its service locations. Visit www.BrooksInstrument.com to locate the
service location nearest to you. However, if traceable calibration equipment is
available at your facility, Brooks Expert Support Tool (BEST), along with train-
ing, is available for purchase.
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