Maintenance
RT-SVX20A-E4
66
To Test Humidity Sensors
Return Air Humidity Sensor
ECA RAH/RAE
Outdoor Humidity Sensor
ECA OAH/OAE
To test this circuit, place a DC milliamp meter in series with either of the leads to the humidity sensor. If the reading
is 0ma, polarity may be reversed. R & - and retest. If the reading does not correspond to the table below,
check the output voltage from the ECA with the sensor disconnected. It should be approximately 20VDC. If so, and
all connections are intact, replace the sensor. If 20VDC is not present, yet the ECA green LED is on, the ECA module
has failed.Humidity sensor accuracy : +/-10% RH.
Table 56 - Humidity sensor test
RH%
DCma
RH%D
Cma
RH%
DCma
100%
20.000
52.6
12.414
31.2
9.000
97.7
19.636
51.7
12.273
30.8
8.926
95.5
19.286
50.8
12.135
30.3
8.852
93.4
18.947
50.0
12.000
29.9
8.780
91.4
18.621
49.2
11.868
29.4
8.710
89.4
18.305
48.4
11.739
29.0
8.640
87.5
18.000
47.6
11.613
28.6
8.571
85.7
17.705
46.8
11.489
28.1
8.504
83.9
17.419
46.1
11.368
27.7
8.438
82.1
17.143
45.3
11.250
27.3
8.372
80.5
16.875
44.6
11.134
26.9
8.308
78.8
16.615
43.9
11.020
26.5
8.244
77.3
16.364
43.2
10.909
26.1
8.182
75.7
16.119
42.5
10.800
25.8
8.120
74.3
15.882
41.8
10.693
25.4
8.060
72.8
15.652
41.2
10.588
25.0
8.000
71.4
15.429
40.5
10.485
24.6
7.941
70.1
15.211
39.9
10.385
24.3
7.833
68.8
15.000
39.3
10.286
23.9
7.826
67.5
14.795
38.7
10.189
23.6
7.770
66.2
14.595
38.1
10.093
23.2
7.714
65.0
14.400
37.5
10.000
22.9
7.660
63.8
14.211
36.9
9.908
22.5
7.606
62.7
14.026
36.4
9.818
22.2
7.552
61.5
13.846
35.8
9.730
21.9
7.500
60.4
13.671
35.3
9.463
21.6
7.448
59.4
13.500
34.7
9.558
21.2
7.397
58.3
13.333
34.2
9.474
20.9
7.347
57.3
13.171
33.7
9.391
20.6
7.297
56.3
13.012
33.2
9.310
20.3
7.248
55.4
12.857
32.7
9.231
20.0
7.200
54.4
12.706
32.2
9.153
53.5
12.558
31.7
9.076
Summary of Contents for Voyager I TSD 060
Page 67: ...Notes 67 RT SVX20A E4...
