Manual 2100-790
Page
22 of 49
Wiring – Main Power
the factory wired on 240V tap. For 208V operation,
reconnect from 240V to 208V tap. The acceptable
operating voltage range for the 240 and 208V taps are:
TAP RANGE
240
253 – 216
208
215 – 197
NOTE:
The voltage should be measured at the field
power connection point in the unit and while
the unit is operating at full load (maximum
amperage operating condition).
For low voltage wiring, an 18 gauge copper, color-coded
cable is recommended. See Table 7 on page 24 for
more information.
Low Voltage Connections
These units use a 24-volt AC low voltage circuit.
C
terminal is
24VAC common and is grounded
.
G
terminal is the
indoor blower input
.
Y1
terminal is the
1st Stage input for cooling.
Y2
terminal is the
2nd Stage compressor input for
cooling (if equipped with an economizer).
B/W1
terminal is the
reversing valve input.
The
reversing valve must be energized for heating mode.
W2
terminal is the
1st stage electric heat
(if equipped).
W3
terminal is the
2nd stage of electric heat
or
emergency heat input
(if equipped).
Two stages of electric
heat are not available on units with dehumidification.
A
terminal is the
ventilation input
. This terminal
energizes any factory-installed ventilation option and
indoor blower.
D
terminal is the dehumidification input. If installed, this
terminal energizes any factory-installed dehumidification
option.
L
terminal is
24 volt alarm active output
.
For units equipped with an alarm relay:
1 terminal
is the
normally closed contact on the relay.
2 terminal
is the
normally open contact on the relay.
3 terminal
is the
common contact on the relay.
DDC Connections
11
terminal is
filter switch, common contact
on
auxiliary terminal strip
(F Control option only)
12
terminal is
filter switch, normally open contact
on
auxiliary terminal strip
(F Control option only)
Unit Shutdown Feature (Standard on All Models)
The RT terminal is the 24VAC transformer output,
and the R terminal is the 24VAC hot terminal for the
operation of the equipment. RT and R are connected
with a brass jumper bar which can be removed and RT
and R connected to an external NC (normally closed)
contact such as a fire/smoke detector that will cause
shutdown of the equipment upon activation.
Electrical shock hazard.
Do not operate this equipment without an
earth ground attached and always disconnect
the remote electric power supplies before
servicing.
Electrical shock can result in serious injury or
death.
!
WARNING
Refer to the unit rating plate for wire sizing information
and maximum fuse or circuit breaker size. Each outdoor
unit is marked with a “Minimum Circuit Ampacity”.
This means that the field wiring used must be sized
to carry that amount of current. Depending on the
installed KW of electric heat, there may be two field
power circuits required. If this is the case, the unit
serial plate will so indicate. All models are suitable
only for connection with copper wire. Each unit and/or
wiring diagram will be marked “Use Copper Conductors
Only”. These instructions
must be
adhered to. Refer to
the National Electrical Code (NEC) for complete current
carrying capacity data on the various insulation grades
of wiring material. All wiring must conform to NEC and
all local codes.
The electrical data lists fuse sizes for all models
including the most commonly used heater sizes. Also
shown are the number of field power circuits required for
the various models with heaters.
The unit rating plate lists a maximum fuse or circuit
breaker that is to be used with the equipment. The
correct size must be used for proper circuit protection
and also to assure that there will be no nuisance
tripping due to the momentary high starting current of
the compressor motor.
The disconnect access door on this unit may be locked
to prevent unauthorized access to the disconnect. To
convert for the locking capability, bend the tab located
in the bottom left-hand corner of the disconnect
opening under the disconnect access panel straight
out. This tab will now line up with the slot in the door.
When shut, a padlock may be placed through the hole
in the tab preventing entry.
See page 28 for important information on three phase
scroll compressor start ups.
See Table 13 on page 39 for electrical specifications.
Wiring – Low Voltage
All 230/208V 1 phase and 3 phase equipment have
dual primary voltage transformers. All equipment leaves
