SSA-SVX06B-EN
39
Installation
2-Speed VFD Units
For 2-Speed VFD controlled units the desired maximum air flow (High Speed) is set by
reprogramming parameter 6-15 on the VFD to the frequency value that best meets the RPM
requirement as shown in the catalog fan tables. The minimum air flow (Low Speed) is set by
reprogramming parameter 6-14 on the VFD. Refer to the table below to see the allowed Low Speed
range for a given High Speed. Use the Menu button and up and down arrows on the keypad to
access the parameters.
Table 14. SZVAV Air Handler Speed to Voltage
Parameter 6-15 Set to 60 Hz
Parameter 6-15 Set to 50 Hz
High Speed
(Hz)
TP1 (RTOM)
Voltage
(Vdc)
High Speed
(Hz)
TP1 (RTOM)
Voltage
(Vdc)
High Speed
(Hz)
TP1 (RTOM)
Voltage
(Vdc)
High Speed
(Hz)
TP1 (RTOM)
Voltage
(Vdc)
44.50
<0.1
52.25
1.65
38.00
<0.1
44.00
1.65
45.02
0.2
52.77
1.7
38.40
0.2
44.40
1.7
45.53
0.3
53.28
1.75
38.80
0.3
44.80
1.75
46.05
0.45
53.80
1.83
39.20
0.45
45.20
1.83
46.57
0.55
54.32
1.9
39.60
0.55
45.60
1.9
47.08
0.7
54.83
1.95
40.00
0.7
46.00
1.95
47.60
0.8
55.35
2
40.40
0.8
46.40
2
48.12
0.95
55.87
2.05
40.80
0.95
46.80
2.05
48.63
1.05
56.38
2.1
41.20
1.05
47.20
2.1
49.15
1.15
56.90
2.13
41.60
1.15
47.60
2.13
49.67
1.25
57.42
2.17
42.00
1.25
48.00
2.17
50.18
1.3
57.93
2.21
42.40
1.3
48.40
2.21
50.70
1.35
58.45
2.27
42.80
1.35
48.80
2.27
51.22
1.45
58.97
2.3
43.20
1.45
49.20
2.3
51.73
1.55
59.48
2.35
43.60
1.55
49.60
2.35
60.00
>2.4
50.00
>2.4
Table 15. 2-Speed VFD Programming Speeds
High Speed
(Hz)
Low Speed
(Hz) Ranges
High Speed
(Hz)
Low Speed
(Hz) Ranges
60.00
25.00 - 39.60
48.00
25 - 31.68
59.00
25.00 - 38.94
47.00
25 - 31.02
58.00
25.00 - 38.28
46.00
25 - 30.36
57.00
25.00 - 37.62
45.00
25 - 29.70
56.00
25.00 - 36.96
44.00
25 - 29.04
55.00
25.00 - 36.30
43.00
25 - 28.38
54.00
25.00 - 35.64
42.00
25 - 27.72
53.00
25.00 - 34.98
41.00
25 - 27.06
52.00
25.00 - 34.32
40.00
25 - 26.40
51.00
25.00 - 33.66
39.00
25 - 25.74
50.00
25.00 - 33.00
38.00
25 - 25.08
49.00
25.00 - 32.34
—
—
