Table 22 — Electric Heater Data, Horizontal Heaters Used in EHS1 (cont)
39T
UNIT SIZE
HEATER
AREA
(Sq Ft)
NO. OF
CONTROL
STEPS
HEATER
COIL
kW
TEMP
RISE
(°F)
MIN COIL
FACE VEL
(Fpm)
POWER SUPPLY, 3-PHASE CIRCUITS
480 Volts 600 Volts
Total FLA No. Sub-Ckts* MWG Fuse Total FLA No. Sub-Ckts* MWG Fuse
07 6.39 3
12 20 300 15 1 12 20 12 1 14 15
17 24 350 21 1 10 30 17 1 10 25
24 30 400 29 1 8 40 24 1 10 30
34 38 450 41 1 6 60 33 1 8 45
45 45 500 55 2 4 70 44 1 6 60
57 52 550 69 2 3 90 55 2 4 70
64 53 600 77 2(U) 3 100 62 2 4 80
09 8.23
3
17 22 300 21 1 10 30 17 1 10 25
24 27 350 29 1 8 40 24 1 10 30
34 33 400 41 1 6 60 33 1 8 45
45 39 450 55 2 4 70 44 1 6 60
64 50 500 77 2(U) 3 100 62 2 4 80
6
78 55 550 94 2 1 125 76 2 3 100
86 56 600 104 3 1 150 83 2 2 110
11 9.67
3
15 17 300 19 1 10 25 15 1 12 20
25 24 350 31 1 8 40 25 1 8 35
39 32 400 47 1 6 60 38 1 6 50
56 41 450 68 2 4 90 54 2 4 70
78 52 500 94 2(U) 1 125 76 2 (U) 3 100
6
90 54 550 109 3 1/0 150 87 2 2 110
112 62 600 135 3 2/0 175 108 3 1/0 150
13 12.77
3
29 24 300 35 1 8 45 28 1 8 35
45 32 350 55 2 4 70 44 1 6 60
64 40 400 77 2(U) 3 100 62 2 4 80
78 43 450 94 2(U) 1 125 76 2 (U) 3 100
92 46 500 111 3 1/0 150 89 2 (U) 2 125
6 119 54 550 144 3 3/0 200 115 3 1/0 150
8 132 55 600 159 4 3/0 200 128 3 2/0 175
17 15.37
3
29 20 300 35 1 8 45 28 1 8 35
45 27 350 55 2 4 70 44 1 6 60
64 33 400 77 2 3 100 62 2 4 80
78 36 450 94 2 1 125 76 2 (U) 3 100
6
92 38 500 111 3 1/0 150 89 2 2 125
119 45 550 144 3 3/0 200 115 3 1/0 150
8 132 46 600 159 4 3/0 200 128 3 (U) 2/0 175
21 18.62
3
45 26 300 55 2 4 70 44 1 6 60
74 36 350 90 2(U) 2 125 72 2 (U) 3 90
99 42 400 120 3 1/0 150 96 2 (U) 1 125
6 119 45 450 144 3 3/0 200 115 3 1/0 150
8
159 55 500 192 4 250 250 154 4 3/0 200
198 62 550 239 5(U) 350 300 191 4 250 250
228 65 600 275 6(U) 500 350 220 5 300 300
26 22.55
3
34 16 300 41 1 6 60 33 1 8 45
74 30 350 90 2(U) 2 125 72 2 (U) 3 90
99 35 400 120 3 1/0 150 96 2 (U) 1 125
6 119 37 450 144 3 3/0 200 115 3 1/0 150
8
159 45 500 192 4 250 250 154 4 3/0 200
212 55 550 256 6(U) 400 350 205 5 (U) 300 300
265 63 600 319 7(U) (2) 250 400 256 6 (U) 400 350
LEGEND
ARI — Air Conditioning & Refrigeration Institute
FLA — Total Full Load Amps of Electric Heating Coils
Fuse — External Fuse Size Required Per Circuit
kW — Kilowatt Rating
MWG — Minimum Wire Gage
VEL — Velocity
*(U) signifies unequal kW per step.
NOTES:
1. Subcircuits are internal heater circuits of 48 A or less ampacity.
2. Minimum wire gage is based on 75 C copper conductors; 3 conductors per
circuit.
IMPORTANT: To avoid damage from overheating, coils must not be
operated at less than minimum airflow (cfm).
Minimum Cfm = Coil Face Area x Minimum Coil Face Velocity
3. Electric heat performance is not within the scope of ARI Standard 430
certification.
4. All ratings shown are at 60 Hz. To obtain kW ratings at 50 Hz when voltage
does not change, multiply the 60 Hz rating by 0.833. For example, a 6-step
heater in a size 32 unit has a rating of 119 kW at 60 Hz. To obtain the
50 Hz rating:
119 x 0.833 = 99 kW at 50 Hz
If the voltage also varies from that shown in the table, use the formula in the
following example to arrive at the correct rating at the new voltage before
multiplying by 0.833:
Given: 2
V
2
()
kW
2
=kW
1
V
1
Where kW
1
= 60 Hz rating
kW
2
= 50 Hz rating
V
1
= 60 Hz voltage
V
2
= 50 Hz voltage
Example: 2
450
kW
2
=119
()
480
kW
2
= 105
105 x 0.833 = 87 kW at 450 v, 50 Hz
208-, 240- and 480-V 208- and 600-V
Heaters. Heaters.
70