Brooks Instrument SLA7840 - Manual (Page 28)

4-4
Model SLA7840
Section 4 Maintenance
& Troubleshooting Installation and Operation Manual
X-PR-SLA7800-RT-eng
Part Number: 541B048AAG
August, 2009
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.
Table 4-1 Sensor Troubleshooting
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