Heat Pump User Manual

32
Legend and Notes for Table 4
LEGEND:
BRKR --- Circuit breaker
CO --- Convenient outlet
DISC --- Disconnect
FLA --- F ull load amps
IFM --- Indoor fan motor
LRA --- Locked rotor amps
MCA --- Minimum circuit amps
P E --- P o w e r e x h a u s t
PWRD CO --- Powered convenient outlet
UNPWR CO --- Unpowered convenient outlet
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. C anadian units may be fuse or circuit
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 d e-
termin e the percentage of voltage imbalance.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
3
3
= 227
Determine maximum deviation from average voltage.
(AB) 227 224 = 3 v
(BC) 231 227 = 4 v
(AC) 227 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
4
227
= 1.76%
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.
Economizer 2 Position Damper
Unit Without Economizer o
r
2 Position Damper
C10333
Fig. 55 -- EconoMi$ert IV Wiring
Step 11 — Adjust Factory--Installed Options
Smoke Detectors
Smoke detector(s) will be connected at the Central
Terminal Board (CTB), at terminals marked “Smoke
Shutdown”. Remove jumper JMP 3 when ready to
energize unit.
EconoMi$er IV Occupancy Switch
Refer to Fig. 55 for general EconoMi$er IV wiring.
External occupancy control is managed through a
connection on the Central Terminal Board.
If external occupancy control is desired, connect a time
clock or remotely controlled switch (closed for Occupied,
open for Unoccupied sequence) at terminals marked
OCCUPANCY on CTB. Remove or cut jumper JMP 2 to
complete the installation.
548J*14D