Factory-Option Thru-Base Connections (Electrical Connections) - Carrier WeatherMaster 48HC Series Installation Instructions Manual

Fig. 40 — Convenience Outlet Utilization
HACR AMP RATING
The amp rating of the HACR factory-installed option is based on
the size, voltage, indoor motor and other electrical options of the
unit as shipped from the factory. If field-installed accessories are
added or changed in the field (for example, power exhaust,
ERV), the HACR may no longer be of the proper amp rating and
therefore will need to be removed from the unit. See unit name-
plate and label on factory-installed HACR for the amp rating of
the HACR that was shipped with the unit from the factory
(Fig. 41). See unit nameplates for the proper fuse, HACR or
maximum over-current protection device required on the unit
with field-installed accessories.
Fig. 41 — HACR Caution Label
FACTORY-OPTION THRU-BASE CONNECTIONS (ELEC-
TRICAL CONNECTIONS)
This service connection kit consists of a
er fitting (brass), a
/ -in. electrical bulkhead connector, all factory-installed in the
3
4
embossed (raised) section of the unit basepan in the condenser
section. The 3 / -in. bulkhead connector enables the low-voltage
4
control wires to pass through the basepan. The
bulkhead connector allows the high-voltage power wires to
pass through the basepan. See Fig. 22 and 23 on page 17.
NOTE: If electrical connections are not going to occur at this time,
tape or otherwise cover the fittings so that moisture does not get
into the building or conduit in the interim.
Check tightness of connector lock nuts before connecting electri-
cal conduits.
Field-supplied and field-installed liquid tight conduit connectors
and conduit may be attached to the connectors on the basepan.
Pull correctly rated high voltage and low voltage through appro-
priate conduits. Connect the power conduit to the internal discon-
nect (if unit is so equipped) or to the external disconnect (through
unit side panel). A hole must be field cut in the main control box
bottom on the left side so the 24-v control connections can be
made. Connect the control power conduit to the unit control box at
this hole.
Downloaded from ManualsNet.com
Notice Label
/ -in. NPT gas adapt-
1
2
1 / -in. electrical bulkhead connector, and a
2
1 /
search engine
UNITS WITHOUT THRU-BASE CONNECTIONS (ELEC-
TRICAL CONNECTIONS)
1. Install power wiring conduit through side panel openings.
Install conduit between disconnect and control box.
2. Install power lines to terminal connections as shown in
Fig. 31 on page 20.
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. On 3-phase units, volt-
ages between phases must be balanced within 2% and the current
within 10%. Use the formula shown in the example below to de-
termine the percent of voltage imbalance. Operation on improper
line voltage or excessive phase imbalance constitutes abuse and
may cause damage to electrical components. Such operation
would invalidate any applicable Carrier warranty.
% Voltage
Imbalance
Example: Supply voltage is 230-3-60
A B C
MOTOR
Average Voltage
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 = 100x
This amount of phase imbalance is satisfactory as it is below the maxi-
mum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.
FIELD CONTROL WIRING
The 48HC unit requires an external temperature control device.
This device can be a thermostat (field-supplied) or a Premier-
Link™ controller (available as factory-installed option or as field-
installed accessory, for use on a Carrier Comfort Network
stand alone control) or the RTU Open Controller for Building
Management Systems using non-CCN protocols (RTU Open is
-in. electrical
2
available as a factory-installed option only).
THERMOSTAT
Install a Carrier-approved accessory thermostat according to in-
stallation instructions included with the accessory. For complete
economizer function, select a two-stage cooling thermostat. Lo-
cate the thermostat accessory on a solid wall in the conditioned
space to sense average temperature in accordance with the ther-
mostat installation instructions. Typical low-voltage connections
are shown in Fig. 42.
23
max voltage deviation from average voltage
= 100 x
average voltage
AB = 224 v
BC = 231 v
AC = 226 v
(224 + 231 + 226)
= =
3
4
= 1.78%
227
681
= 227
3
® or as a