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Table 13 — Capacity Control Steps (cont)
30GT
UNIT SIZE
CONTROL
STEPS
LOADING SEQUENCE A
LOADING SEQUENCE B
%
Displ.
(Approx)
Compressors
%
Displ.
(Approx)
Compressors
130
(60 Hz)
A1†, B1†
1
14
A1*
14
B1*
2
29
A1*,B1*
29
A1*,B1*
3
36
A1*,B1
36
A1,B1*
4
43
A1,B1
43
A1,B1
5
64
A1*,A2,B1
64
A1,B1*,B2
6
72
A1,A2,B1
72
A1,B1,B2
7
93
A1*,A2,B1,B2
93
A1,A2,B1*,B2
8
100
A1,A2,B1,B2
100
A1,A2,B1,B2
130
(50 Hz)
A1†, B1†
1
10
A1*
16
B1*
2
21
A1*,B1*
21
A1*,B1*
3
29
A1*,B1
32
A1,B1*
4
34
A1,B1
34
A1,B1
5
47
A1*,A2,B1
56
A1*,B1,B2
6
58
A1,A2,B1
64
A1,B1,B2
7
77
A1*,A2,B1,B2
74
A1,A2,B1*,B2
8
82
A1,A2,B1,B2
82
A1,A2,B1,B2
9
95
A1*,A2,A3,B1,B2
92
A1,A2,A3,B1*,B2
10
100
A1,A2,A3,B1,B2
100
A1,A2,A3,B1,B2
150,230A,245A,255A
(60 Hz)
A1†, B1†
1
11
A1*
17
B1*
2
19
A1*,B1*
19
A1*,B1*
3
28
A1*,B1
33
A1,B1*
4
33
A1,B1
33
A1,B1
5
44
A1*,A2,B1
58
A1*,B1,B2
6
58
A1,A2,B1
67
A1,B1,B2
7
78
A1*,A2,B1,B2
75
A1,A2,B1*,B2
8
83
A1,A2,B1,B2
83
A1,A2,B1,B2
9
94
A1*,A2,A3,B1,B2
92
A1,A2,A3,B1*,B2
10
100
A1,A2,A3,B1,B2
100
A1,A2,A3,B1,B2
150,230A,245A,255A
(50 Hz)
A1†, B1†
1
13
A1*
13
B1*
2
27
A1*,B1*
27
A1*,B1*
3
33
A1*,B1
33
A1,B1*
4
40
A1,B1
40
A1,B1
5
53
A1*,A2,B1
53
A1*,B1,B2
6
60
A1,A2,B1
60
A1,B1,B2
7
73
A1*,A2,B1,B2
73
A1,A2,B1*,B2
8
80
A1,A2,B1,B2
80
A1,A2,B1,B2
9
93
A1*,A2,A3,B1,B2
93
A1,A2,A3,B1*,B2
10
100
A1,A2,A3,B1,B2
100
A1,A2,A3,B1,B2
170,270A,330A/B
(60 Hz)
A1†, B1†
1
11
A1*
11
B1*
2
22
A1*,B1*
22
A1*,B1*
3
28
A1*,B1
28
A1,B1*
4
33
A1,B1
33
A1,B1
5
44
A1*,A2,B1
44
A1,B1*,B2
6
50
A1,A2,B1
50
A1,B1,B2
7
61
A1*,A2,B1,B2
61
A1,A2,B1*,B2
8
67
A1,A2,B1,B2
67
A1,A2,B1,B2
9
78
A1*,A2,A3,B1,B2
78
A1,A2,B1*,B2,B3
10
83
A1,A2,A3,B1,B2
83
A1,A2,B1,B2,B3
11
94
A1*,A2,A3,B1,B2,B3
94
A1,A2,A3,B1*,B2,B3
12
100
A1,A2,A3,B1,B2,B3
100
A1,A2,A3,B1,B2,B3
170,270A,330A/B,360B
(50 Hz)
A1†, B1†
1
10
A1*
10
B1*
2
24
A1*,B1*
24
A1*,B1*
3
29
A1*,B1
24
A1,B1*
4
29
A1,B1
28
A1,B1
5
43
A1*,A2,B1
43
A1,B1*,B2
6
43
A1,A2,B1
48
A1,B1,B2
7
57
A1*,A2,B1,B2
57
A1,A2,B1*,B2
8
62
A1,A2,B1,B2
62
A1,A2,B1,B2
9
76
A1*,A2,A3,B1,B2
76
A1,A2,B1*,B2,B3
10
81
A1,A2,A3,B1,B2
81
A1,A2,B1,B2,B3
11
95
A1*,A2,A3,B1,B2,B3
95
A1,A2,A3,B1*,B2,B3
12
100
A1,A2,A3,B1,B2,B3
100
A1,A2,A3,B1,B2,B3
LEGEND
Displ. — Displacement (Approximate)
*Compressor unloaded.
†Compressor unloader, standard.
**Compressor unloader, accessory.
NOTES:
1. The microprocessor selects loading sequence A or B, which in turn determines the compressor
circuit that is energized first. This evens out operating hours on each circuit over an extended period
of time.
2. The staging of modular units (30GT230-420) will be random due to variables within the system. The
loading sequence of each individual module will be as listed.
3. If unit operation is anticipated with system load below minimum unloaded capacity of chiller:
a. Consider using 2 smaller units in place of the larger unit.
b. Increase fluid loop volume to ensure adequate run time (see Application Data section in Product
Data literature).
c. Consider adding accessory hot gas bypass package.
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