Teledyne 300M - Manual (Page 105)

Teledyne API Model 300M CO Analyzer Instruction Manual, 04033, Rev. A
If temperature sensor readings appear accurate but control temperatures are not being maintained
at their proper value, check the operation of the heaters as follows:
1. Observe the indicator LED's on the Power Supply Module and confirm that the red (right-
most) LED is lit, and that the "CEL HTR" LED is lit or cycling (turning off and on). If these
indicators are not correct, it is probably that the Power Supply Module, or the V/F Board is
faulty. Check as described in Sections 10.2 and 10.6.3.
2. Unplug the heater element from Power Supply Module and confirm that 115 VAC is present.
If 115 VAC is present, the heater element has failed and should be replaced.
WARNING
Hazardous voltages present - use caution.
10.6.3 Checking the V/F Card
A schematic and physical diagram of the V/F card are shown on Drawings 514 and 515 in
Appendix C. The V/F is a multi-function I/O card that connects to the microprocessor via a STD
Bus interface, and acts as the primary I/O interface between the microprocessor and the rest of
the analyzer. All functions of the board are performed under control of the microprocessor.
Proper operation of the V/F board can be confirmed by performing an ADC calibration
procedure as described in Section 9.2. If this calibration procedure can be performed correctly, it
is highly probable that the V/F card is functioning properly.
If the V/F does not function properly, check the following:
1. Confirm the presence of appropriate power by checking for:
A. +5 V between TP 4 and TP 5
B. +15 V at TP 1 and TP 3
C. -15 V at TP 2 and TP 3
If any of these voltages are incorrect, check the DC Power Supply as described in Section 10.6.4.
2. Confirm that all jumpers and switches on the V/F board are set properly, as follows in
Table 10-3.
10-11