Van Air Systems Dew Point Meter 46-2529 2-02 User Manual
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Terminal No. TB5
Function (Terminal TB5 is not available on 24V versions)
1
Pump power Hot (115VAC)
2
Pump power Neutral (115VAC)
OPERATION & MAINTENANCE
Field calibration of the Hygrosensor is impractical. To ensure continued accuracy, it is recommended
that the sensor be replaced annually.
Circuit Calibration
NOTE:
6392N is supplied fully factory calibrated. This procedure is only necessary if
circuit is thought to be malfunctioning.
1.
Apply power and measure TAB of U201 (Voltage Regulator near side of PC Board). Adjust P4
for 5.00V.
2.
With no sensor connected to terminals A and B, measure PIN 6 of U7. Check for 0.0V+0.05V.
Check terminal 3 of TB3 for 4.0mA+0.1mA.
3.
Place a jumper across sensor terminals A and B and adjust P1 for 5.00V at PIN 6 of U7. Check
terminal 3 of TB3 for 12.0mA+0.1mA.
4.
If these parameters cannot be met, contact Newport Scientific about factory service on PC board.
Alarm Set Point Adjustment
Locate the display function switch (S1). Note that only one position of this switch should be
ON at a time.
1.
To view and adjust relay #1 setpoint, turn the #1 position of SI OFF and the SET1 position #2
ON. Turn the SET1 of P2 near the switch to the desired setpoint.
2.
If board is a dual relay version, relay #2 can be adjusted similarly by turning SET1 position
OFF and SET2 position ON. Now adjust the SET2 of potentiometer P3.
3.
When finished adjusting the setpoints, return S1 to the default operating mode by turning OPER
position ON and all others OFF.
A small red LED near the potentiometer P2 or P3 indicates when an alarm is occuring.