TM 5-3895-374-24-2
to 5.22 volts DC.
6.
If out of range, continue monitoring the voltage and unplug the CRT, BLEND & FEEDER cards.
7.
If still out of range, replace the POWER SUPPLY card.
8.
Plug in the CRT card.
9.
If now out of range, replace the CRT card.
10.
Plug in the BLEND card.
11.
If now out of range, replace the BLEND card.
12.
Plug in the FEEDER card.
13.
If now out of range, replace the FEEDER card.
If in range, replace the SINGLE BOARD COMPUTER (SBC) card and repeat tests beginning at step 5.
Incorrect Liquid Asphalt Temperature Display
Inspect all sensor cables and connections.
1.
Measure the sensor DC output voltage at terminals 9 (+) and 10 (-) on the BLEND I/O strip. The voltage scaling
factor should be within the range of (0.0 to 1.1 volt DC) per 100° F.
2. If the voltage is 1, go to PROCEDURE 3, SENSOR EXCITATION VOLTAGE.
3. If the measured voltage is out of the expected range, re-calibrate the probe according to the users manual.
4. If the measured voltage is out of the expected range, disconnect the asphalt temperature probe from the AC
TEMPERATURE PROBE AMPLIFIER and measure its resistance. The theoretical resistance should be 100
ohms plus 0.214 ohms per degree F above 32 degree F. (IE at 300F --- 100 + 270 * .214 = 158 ohms)
5. If the measured resistance equals the theoretical resistance within 10% replace the AC TEMPERATURE PROBE
AMPLIFIER and re-calibrate the sensor according to procedures in the operators manual.
6. If the measured resistance does not equal the calculated resistance within 10%, replace the temperature probe
and re-calibrate the sensor according to procedures in the operators manual.
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