Specifications

46
ELECTRIC HEATING CAPACITIES
*Two heater packages required to provide kW indicated.
†009 for 551B102 units.
**On units with factory-installed outlet, use CRSINGLE014A00.
NOTES:
1. The kW ratings shown above are at 240, 480, and 575 v. Use the Multiplication Factors
table below to determine heater capacity for your particular voltage.
MULTIPLICATION FACTORS
Example: 32.0 kW (at 240 v) heater on 208 v
= 32.0 (.75 mult factor)
= 24.0 kW capacity at 208 v
2. Heaters are not available for size 036-072 575-v units.
LEGEND AND NOTES FOR ELECTRICAL DATA TABLES
LEGEND
*Used to determine minimum disconnect per NEC.
†Heater capacity (kW) is based on heater voltage of 208 v, 240 v, 480 v or 575 v. If power dis-
tribution voltage to unit varies form rated heater voltage, heater kW will vary accordingly.
**Fuse or HACR circuit breaker per NEC.
††Units have 2 condenser-fan motors.
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equipment (refer
to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuse or
HACR breaker.
2.
Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply voltage is greater than 2%.
Use
the following formula to determine the percent of voltage imbalance.
% Voltage Imbalance
Example: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
= 457
Determine maximum deviation from average voltage.
(AB) 457 – 452 = 5 v
(BC) 464 – 457 = 7 v
(AC) 457 – 455 = 2 v
Maximum deviation is 7 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
= 1.53%
This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.
3. Non-fused disconnect switch cannot be used when rooftop unit electrical ratings exceed
80 amps.
4. 575-v units have UL, Canada approval only. Electric heaters are not available for 036-
072, 575-v units.
UNIT
551B
VOLTAGE
(60 Hz)
ACCESSORY
kW
ACCESSORY
HEATER
PART NUMBER
CRHEATER---A00
ACCESSORY
SINGLE
POINT BOX
PART NO.
CRSINGLE---A00
036
208/230
(single phase)
4.4 101 —
6.5 102 —
8.7 103 —
10.5 104 002
13.0* 102* 002
208/230
(3 phase)
4.4 101 —
6.5 102 —
8.7 103 —
10.5 104 —
16.0 105 —
460
(3 phase)
6.0 106 —
8.8 107 —
11.5 108 —
14.0 109 —
048
208/230
(single phase)
4.4 101 —
8.7 103 —
13.0* 102* 002
17.4* 103* 002
21.0* 104* 002
208/230
(3 phase)
6.5 102 —
8.7 103 —
16.0 105 —
21.0* 104* 002
460
(3 phase)
6.0 106 —
11.5 108 —
14.0 109 —
23.0* 108* —
060
208/230
(single phase)
6.5 102 —
8.7 103 002
13.0* 102* 002
17.4* 103* 002
21.0* 104* 002
208/230
(3 phase)
6.5 102 —
10.5 104 —
16.0 105 002
21.0* 104* 002
26.5* 105,104 002
460
(3 phase)
6.0 106 —
11.5 108 —
14.0 109 —
23.0* 108* —
25.5* 109,108 —
UNIT
551B
VOLTAGE
(60 Hz)
ACCESSORY
kW
ACCESSORY
HEATER
PART NUMBER
CRHEATER---A00
ACCESSORY
SINGLE
POINT BOX
PART NO.
CRSINGLE---A00
072
208/230
(3 phase)
6.5 102 —
10.5 104 —
16.0 105 002
21.0* 104* 002
26.5* 105,104 002
460
(3 phase)
6.0 106 —
11.5 108 —
14.0 109 —
23.0* 108* —
25.5* 109,108 —
090,
102
208/230
(3 phase)
10.5 117 006
16.0 110 006
24.8 111 007
32.0 112 007
42.4* 112,117 007†
460
(3 phase)
14.0 116 006
16.5 113 006
27.8 114 006
33.0 115 006
41.7* 114,116 008
575
(3 phase)
17.0 118 006
34.0 119 006
120,
150
208/230
(3 phase)
10.5 117 012
16.0 110 012
32.0 112 012
42.4* 112,117 015
50.0* 112,110 015
460
(3 phase)
16.5 113 011
27.8 114 011
33.0 115 011**
41.7* 114,116 014
50.0* 115,113 014
575
(3 phase)
17.0 118 011
34.0 119 011
51.0* 119,118 014
HEATER kW
RATING
VOLTAGE DISTRIBUTION
V/3/60
MULTIPLICATION
FACTOR
240
200
208
230
240
.69
.75
.92
1.00
480
440
460
480
.84
.92
1.00
FLA —
Full Load Amps
HACR —
Heating, Air Conditioning and Refrigeration
IFM —
Indoor (Evaporator) Fan Motor
LRA —
Locked Rotor Amps
MCA —
Minimum Circuit Amps
MOCP —
Maximum Overcurrent Protection
NEC —
National Electrical Code
OFM —
Outdoor (Condenser) Fan Motor
RLA —
Rated Load Amps
UL —
Underwriters’ Laboratories
= 100 x
max voltage deviation from average voltage
average voltage
Average Voltage =
452 + 464 + 455
3
=
1371
3
IMPORTANT:
If the supply voltage phase imbalance is more than 2%, contact your local
electric utility company immediately.
7
457