Reznor YDSA Unit Installation Manual - Manual (Page 24)

Form I-Y, P/N 273646R6, Page 24
FIGURE 17A - Disconnect Switch Wiring Connections
Field-supplied or
Option CP
Disconnect Switch
Field-supplied or Option CP
Disconnect Switch (No BA Option)
Supply V
oltage
(See MCA
on rating plate to
determine wire size.)
Supply V
oltage
(See MCA
on rating plate to
determine wire size.)
Supply V
oltage
(See MCA
on rating plate to
determine wire size.)
Field wiring
Factory wiring
GRD
G
Option BA6 Lockable Disconnect Switch
or Circuit 1 of Option BA7 Dual Lockable Disconnects
Green
Green
Field-supplied or
Option CP
Disconnect Switch
Circuit 2 of Option BA7 Dual Lockable Disconnects
GRD
L3 T3
T1 L1
Black L1
L3
L2 T2
L2
GRD
L3 T3
T1 L1
L2 T2
G
H
J
DUAL POWER
CIRCUITS
(Option BA7)
CIRCUIT 1 is for DX equipment (compressors, condenser fans,
optional phase/loss monitor, and associated contactors).
CIRCUIT 2 is for the blower, all dampers, optional heating section, optional
power exhust or energy recovery wheel, and other non-DX components.
L1
L2
L3
Yellow
Red
Black
Yellow
Red
Option BA6
Disconnect
Switch
Opening
for Power
Supply
Option BA7
Disconnect
Switches
Openings
for Power
Supplies
Circuit 1
Circuit 2
FIGURE 17B - Built-
in Disconnect Switch
Options BA6 and BA7
7.2.2 Supply Voltage The electric supply to the unit must meet stringent requirements for the system to oper-
ate properly. Voltage supply should be within ±10% or as stated on the rating plate.
Maximum imbalance on a 3-phase system is 2%.
If the power supply is not within these tolerances, contact the power company prior to
operating the system.
CAUTION: If this unit is allowed to operate on an electric supply that is
not within the specified tolerances, the product warranty shall be void.
Follow instructions below to check.
Check Voltage Supply - See voltage use range on the rating plate. Measure (and
record) each supply leg voltage at all line disconnect switches. Readings must fall
within the allowable range.
Check Voltage Imbalance - In a 3-phase system, excessive voltage imbalance
between phases will cause compressor motors to overheat and eventually fail. Maxi-
mum allowable imbalance is 2%. To determine voltage imbalance, use recorded volt-
age measurements taken above in the following formula.
Key: V1, V2, V3 = line voltages as measured
VA (average) =
(V1 + V2 + V3)
3
VD = line voltage (V1, V2, or V3) that deviates farthest from average (VA)
Formula:
% Line Voltage Imbalance =
[100 x (VA - VD)]
VA
7.2 Supply Wiring (cont’d)
7.0 Electrical and Wiring (cont'd)
7.2.1 Disconnect Switch (cont’d)