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Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 55 of 83
Verifying Liquid Pressure Transducer Operation
Using a multimeter set to VDC with the Liquid Pressure Transducer connected to the “Liq P” 3-pin connector on the control
board. Pin 1 (Red wire +5VDC) to Pin 3 (Black wire - GND) should read 5 VDC continuous. Pin 2 (Blue wire output from
transducer) to Pin 3 (Black - GND) should read 0.5 to 4.5 VDC and will vary depending on liquid~ pressure measured. See
Table 17.
VDC
Figure 27. Liquid Pressure Transducer Voltage
Liquid Pressure
(PSIG)
DC Voltage Output
(Pin 2 to Pin 3)
Liquid Pressure
(PSIG)
DC Voltage Output
(Pin 2 to Pin 3)
0
0.50
260
2.58
10
0.58
270
2.66
20
0.66
280
2.74
30
0.74
290
2.82
40
0.82
300
2.90
50
0.90
310
2.98
60
0.98
320
3.06
70
1.06
330
3.14
80
1.14
340
3.22
90
1.22
350
3.30
100
1.30
360
3.38
110
1.38
370
3.46
120
1.46
380
3.54
130
1.54
390
3.62
140
1.62
400
3.70
150
1.70
410
3.78
160
1.78
420
3.86
170
1.86
430
3.94
180
1.94
440
4.02
190
2.02
450
4.10
200
2.10
460
4.18
210
2.18
470
4.26
220
2.26
480
4.34
230
2.34
490
4.42
240
2.42
500
4.50
250
2.50
Table 17. Liquid Pressure Transducer Output Voltage