Product manual

McQuay IM 782-4 17
Installation Guidelines
Electric Heat kW Options
Heater Amps
Table 3: Heater Amps
Electric Heat Safety
Overcurrent Protection
Overcurrent fuse protection is provided for each stage of
electric heat (in lieu of one per 48 amperes).
Thermal (Over Temperature) Protection
Primary - Automatic limit switches, one per step (120°F or
150°F as appropriate).
Backup - Manual reset thermal cutout (180°F).
Fan Interlock Method:
To prevent the heater from being energized unless the fan is
on, the heater includes two interlock methods: an airflow
switch, and the use of an auxiliary contact in the motor starter
contactor (3ph) or a fan relay (1ph).
Airflow Switch:
The airflow switch provides the best means of protection
against air failure caused by fan belt or other malfunction.
Switches are of the differential pressure, diaphragm-operated
type and require a minimum total pressure differential of .05"
WC. The switch is factory wired in series with the manual
reset cutout.
Table 2: KW Options by Unit Size
Unit Size
002 003 004 005 007 010
KW Range
1.5 -
10
2.5 -
20
2.5 -
20
4 - 26 6 - 38 6 - 55
V
oltagePhase11.5 2 2.533.544.555.566.57
120 1
8.33 12.50 16.67 20.83 25.00 29.17 33.33 37.50 41.67 45.83 50.00 54.17 58.33
240 1
4.17 6.25 8.33 10.42 12.50 14.58 16.67 18.75 20.83 22.92 25.00 27.08 29.17
240 3
2.41 3.61 4.82 6.02 7.23 8.43 9.63 10.84 12.04 13.25 14.45 15.66 16.86
480 3
1.20 1.81 2.41 3.01 3.61 4.21 4.82 5.42 6.02 6.62 7.23 7.83 8.43
600 3
0.96 1.45 1.93 2.41 2.89 3.37 3.85 4.34 4.82 5.30 5.78 6.26 6.74
V
oltage Phase 7.5 8 8.5 9 10 11 12 13 14 15 16 17
120 1
62.50 66.67 70.83 75.00 83.33 91.67 100.00 108.33 116.67 125.00 133.33 141.67
240 1
31.25 33.33 35.42 37.50 41.67 45.83 50.00 54.17 58.33 62.50 66.67 70.83
240 3
18.06 19.27 20.47 21.68 24.08 26.49 28.90 31.31 33.72 36.13 38.54 40.94
480 3
9.03 9.63 10.24 10.84 12.04 13.25 14.45 15.66 16.86 18.06 19.27 20.47
600 3
7.23 7.71 8.19 8.67 9.63 10.60 11.56 12.52 13.49 14.45 15.41 16.38
V
oltage Phase 18 19 20 22 24 26 28 30 32 34 36 38
120 1
150.00 158.33 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
240 1
75.00 79.17 83.33 91.67 100.00 108.33 116.67 125.00 133.33 141.67 150.00 158.33
240 3
43.35 45.76 48.17 52.99 57.80 62.62 67.44 72.25 77.07 81.89 86.71 91.52
480 3
21.68 22.88 24.08 26.49 28.90 31.31 33.72 36.13 38.54 40.94 43.35 45.76
600 3
17.34 18.30 19.27 21.19 23.12 25.05 26.97 28.90 30.83 32.76 34.68 36.61
V
oltage Phase 40 45 50 55
120 1
N/A N/A N/A N/A
240 1
N/A N/A N/A N/A
240 3
96.34 108.38 120.42 132.47
480 3
48.17 54.19 60.21 66.23
600 3
38.54 43.35 48.17 52.99
KW
KW
KW
KW