2000-OSM, F1
6-13
Any one of the following alarm messages or conditions could be present:
On Background Screen
***ALARM:*** (flashing)
On Manual Temperature
Zone (3) (flashing)
Control Mode Screen
*Temp Bd Alarm* (flashing)
On
Alarm
Screen
Temperature
Board:
*Zone
Specific
*Analysis
Shutdown
***
TEMP
ZONE
(#)
Alarm
***
*Reasonableness
Test
*Probe
Open/Shorted
or
TC
Faulty
*Low Temp
Failure: The failure is most likely isolated to the zone indicating a temperature less than -200 deg C.
The temperature sensor(s) is a 400 ohm platinum thermocouple probe. As the temperature of the
probe increases, its resistance value increases. As the temperature of the probe decreases, the
resistance value decreases. The maximum scaled temperature range measurable by the
temperature controller is -200 degrees. This corresponds to an extremely low resistance at the
sensor input. The least resistance possible is a short circuit to the sensor input or shorted probe or
connection.
Cause: The sensor to the zone input has possibly shorted. Perform
Test Procedure 22
(Shorted
Temperature Sensor).
Isothermal Oven Heater Thermocouple Faulty
Symptom: At the temperature board in electronics enclosure, all LED’s are off as the temperature
control board shuts down.
Any one of the following alarm messages or conditions could be present:
On Background Screen
***ALARM:*** (flashing)
On Manual Temperature
*Temp Bd Alarm* (flashing)
Control Mode Screen
On
Alarm
Screen
Temperature
Board:
Heater
Barrel
TC
Faulty
*Analysis
Shutdown
Failure: The isothermal oven heater temperature is greater than 500 degrees C.
Cause: The sensor input from the isothermal oven heater temperature monitor has opened, or is no
longer connected.
Perform
Test Procedure 24
(Isothermal Oven Overtemp Sensor Open).
Temperature Control Micro #2
Symptom: Micro chip #2 monitors for over temperature conditions at the various temperature zones.
No heat being applied to a specific temperature zone. Actual temperature as indicated in Manual
Temperature Control Mode indicates greater than 500 deg C for a specific zone. At the temperature
board in electronics enclosure, all LED’s are off as the temperature control board shuts down.