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LEGEND
FLA
— Full Load Amps
LRA
— Locked Rotor Amps
MCA
— Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection
RLA
— Rated Load Amps
*Heater capacity (KW) based on heater voltage of 208v, 240v, & 480v.
If power distribution voltage to unit varies from rated heater voltage,
heater KW will vary accordingly.
NOTES:
1. In compliance with NEC (National Electrical Code) requirements
for multimotor and combination load equipment (refer to NEC
Articles 430 and 440), the overcurrent protective device for the
unit shall be Power Supply fuse . The CGA (Canadian Gas
Association) units may be fuse or circuit breaker.
2. Minimum wire size is based on 60 C copper wire. If other than
60 C wire is used, or if length exceeds wire length in table,
determine size from NEC.
3. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply volt-
age is greater than 2%. Use the following formula to determine
the percentage of voltage imbalance.
% Voltage imbalance
max voltage deviation from average voltage
= 100 x
average voltage
C
O
R
G
Y
E
W2
THERMOSTAT
AND SUBBASE
Fig. 17—Control Connections
®
Fig. 16—Electrical Data Legend
BRN
ORN
RED
GRN
YEL
WHT
UNIT CONTROL POWER
SPLICE BOX
C99056
EXAMPLE: Supply voltage is 460-3-60.
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
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is
more than 2%, contact your local electric utility company
immediately.
SINGLE-PHASE
CONNECTIONS
TO DISCONNECT
PER NEC
3-PHASE
CONNECTIONS
LEGEND
NEC – National Electrical Code
Field Wiring
Splice Connections
Fig. 18—Line Power Connections
—14—
AB = 452 v
BC = 464 v
AC = 455 v
452 + 464 + 455
Average Voltage =
3
1371
=
3
= 457
7
457
= 1.53%
GROUND LUG
(IN SLPICE BOX)
GROUND
LEAD
L1
L2
L3
NOTE: Use copper wire only.
C99024
BLK
YEL
BLU
C99057
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