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Connect field power supply conductors to LINE side termi-
nals when the switch enclosure cover is removed to attach the
handle.
Field-Install the NFD Shaft and Handle
1.
Remove the Control Box access panel. The NFD enclo-
sure is located below the Control Box (see Fig. 27).
2.
Remove (3) cap head screws that secure the NFD enclo-
sure front cover — (2) on the face of the cover and (1) on
the left side cover. See Fig. 28.
3.
Remove the front cover of the NFD enclosure.
4.
Make sure the NFD shipped from the factory is at OFF
position (the arrow on the black handle knob is at OFF).
5.
Insert the shaft with the cross pin on the top of the shaft in
the horizontal position. See Fig. 28.
6.
Measure from the tip of the shaft to the top surface of the
black pointer; the measurement should be 3.75 to 3.88 in.
(95 to 99 mm).
7.
Tighten the locking screw to secure the shaft to the NFD.
8.
Turn the handle to the OFF position with red arrow point-
ing at OFF.
9.
Install the handle on to the painted cover horizontally with
the red arrow pointing to the left.
10. Secure the handle to the painted cover with (2) screws and
lock washers supplied.
11. Engaging the shaft into the handle socket, re-install (3)
hex screws on the NFD enclosure.
12. Re-install the unit front panel.
Fig. 27 — NFD Enclosure Location
Fig. 28 — NFD Handle and Shaft Assembly
UNITS WITHOUT FACTORY-INSTALLED NON-FUSED
DISCONNECT
When installing units, provide a disconnect switch per NEC
(National Electrical Code) of adequate size. Disconnect sizing
data is provided on the unit informative plate. Locate on unit
cabinet or within sight of the unit per national or local codes.
Do not cover unit informative plate if mounting the disconnect
on the unit cabinet.
ALL UNITS
All field wiring must comply with NEC and all local codes.
Size wire based on MCA (Minimum Circuit Amps) on the unit
informative plate. See Fig. 25 and the unit label diagram for
power wiring connections to the unit power terminal blocks
and equipment ground. Maximum wire size is #2ga AWG
(copper only) per pole on contactors. See Fig. 25 and unit label
diagram for field power wiring connections.
Provide a ground fault and short circuit over-current protec-
tion device (fuse or breaker) per NEC Article 440 (or local
codes). Refer to unit informative data plate for MOCP (Maxi-
mum Over-Current Protection) device size.
All units except 208/230v units are factory wired for the
voltage shown on the nameplate. If the 208/230v unit is to be
connected to a 208v power supply, the control transformer
must be rewired by moving the black wire with the
male spade connector from the 230v connection and moving it
to the 200v
1
/
-in. male terminal on the primary side of the
4
transformer. Refer to unit label diagram for additional infor-
mation. Field power wires will be connected at line-side pres-
sure lugs on the power terminal block or at factory-installed
option non-fused disconnect.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. On 3-phase
units, voltages between phases must be balanced within 2%
and the current within 10%. Use the formula shown in the ex-
ample below to determine the percent of voltage imbalance.
Operation on improper line voltage or excessive phase imbal-
ance constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any applicable
Bryant warranty.
Example: Supply voltage is 230-3-60
A
B
C
AB = 224 v
BC = 231 v
AC = 226 v
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 maximum
allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact
your local electric utility company immediately.
NOTE: Check all factory and field electrical connections for
tightness.
17
(224 + 231 + 226)
681
=
=
3
3
4
= 1.78%
227
1
/
-in. fe-
4
227
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