Teledyne T360M User Manual

Page of 358
Teledyne API Model T360/T360M Operation Manual 
Troubleshooting and Service 
 
251 
8.5.7.4. IR SOURCE 
The IR source can be checked using the following procedure: 
1.  Disconnect the source and check its resistance when cold.  When new, the 
source should have a cold resistance of more than 1.5 Ohms but less than 
3.5 Ohms.  If not, then the source is bad. 
2.  With the source disconnected, energize the analyzer and wait for it to start 
operating.  Measure the drive Voltage between pins 1 and 2 on the jack that 
the source is normally connected to; it should be 11.5 ± 0.25 VDC.  If not, 
then there is a problem with either the wiring, the Relay Board, or the +12V 
power supply. 
3.  If the drive voltage is correct in step 2, then remove the source from the heat 
sink assembly (2 screws on top) and connect to its mating connector.  
Observe the light being emitted from the source.  It should be centered at the 
bottom of the U-shaped element.  If there is either no emission or a badly 
centered emission then the source is bad. 
8.5.7.5. PRESSURE/FLOW SENSOR ASSEMBLY 
The pressure/flow sensor PCA, located on the top of the absorption bench, can be 
checked with a Voltmeter using the following procedure which, assumes that the 
wiring is intact, and that the motherboard and the power supplies are operating 
properly.  
  For Pressure related problems: 
  Measure the voltage across C1 it should be 5 ± 0.25 VDC.  If not then 
the board is bad. 
  Measure the voltage across TP4 and TP1.  With the sample pump 
disabled it should be 4500 mV ±250 mV.  With the pump energized it 
should be approximately 200 mV less.  If not, then S1, the pressure 
transducer is bad, the board is bad, or there is a pneumatic failure 
preventing the pressure transducer from sensing the absorption cell 
pressure properly. 
  For flow related problems: 
  Measure the voltage across TP2 and TP1 it should be 10 ±0.25 VDC.  If 
not then the board is bad. 
  Measure the voltage across TP3 and TP1.  With proper flow (800 cc/min 
at the sample inlet) this should be approximately 4.5V (this voltage will 
vary with altitude).  With flow stopped (sample inlet blocked) the voltage 
should be approximately 1V.  If the voltage is incorrect, the flow sensor is 
bad, the board is bad or there is a leak upstream of the sensor. 
07272B DCN6552