Teledyne API Model 200AH NO
X
Analyzer Instruction Manual, 06492, Rev. G2
5-13
DC Power Supply Voltage (DCPS)
The DCPS voltage is a composite of the 5 and 15 VDC voltages in the Power Supply Module.
This is meant to be a quick indicator to show if the PSM is working correctly. The nominal value
is 2500 mV 200 mV.
Reaction Cell Temperature (RCEL TEMP)
This is a measurement of the temperature of the reaction cell. It is controlled by the computer to
50 2C. Temperatures outside this range will cause the M200AH output to drift.
Box Temperature (BOX TEMP)
This TEST function measures the temperature inside the chassis of the M200AH. The
temperature sensor is located on the Status/Temp Board. Typically it runs 2 to 10C higher than
the ambient temperature. The M200AH has been engineered to maintain stable output over 5 to
40C ambient temperature range.
PMT Temperature (PMT TEMP)
The temperature of the PMT is closely controlled by a dedicated proportional temperature
controller. The nominal set-point is 7 1C. Readings outside this range will cause instrument
drift due to gain changes in the PMT detector.
Block Temperature (BLOCK TEMP)
The block temperature is the temperature of the sample flow orifice. The block is mounted near
the rear of the instrument and is located upstream of the converter. Running the converter at low
pressure improves its conversion efficiency. The normal temperature of the sample orifice block
is 50 2C, and is controlled by the computer.
Oxygen Sensor Temperature (O
2
TEMP) (Option)
For instruments equipped with O
2
sensor option, the O
2
temperature reading replaces the Block
Temp reading and is the temperature of the oven housing the O
2
sensor. Also included the oven
is the sample flow control orifice. The normal temperature of the oven is 50 2°C, and is
controlled by the computer.
Converter Temperature (CONV TEMP)
The converter temperature monitors the temperature of the NO
2
-to-NO converter and is
controlled by the computer. The nominal set-point is 700 10°C. The temperature sensor inside
the converter is a type-K thermocouple. The thermocouple amplifier is located on the
STATUS/TEMP board. If the thermocouple breaks, the circuit will turn off power to the heater.
