4. Open one of the thermistor connections to allow air to
escape the vessel and the anti-freeze to enter.
5. At the beginning of the next cooling season, refill cooler,
add recommended inhibitor, and replace FU1 (if
removed).
Step 5 — Make Electrical Connections —
The
electrical characteristics of the available power supply must
agree with the unit nameplate rating. Supply voltage must
be within the limits shown. The control box is divided into
field power side on the right, and control power supply on
the left (when facing control box) on 080-110 and associ-
ated modular units. (See Table 1.) On 130-210 and associ-
ated modular units (see Table 1), the power box is located on
the cooler side of the unit, and the control box is located on
the compressor side.
FIELD POWER CONNECTIONS (See Fig. 11-15) — All
power wiring must comply with applicable local and
national codes. Install field-supplied, branch circuit fused
disconnect(s) of a type that can be locked off or open. Dis-
connect(s) must be located within sight from and readily ac-
cessible from unit in compliance with NEC Article 440-14.
See Tables 4A-7 for unit electrical data.
IMPORTANT: The 30GT080-420 units have a factory-
installed option for a non-fused disconnect for power
and control entry. If the unit is equipped with this op-
tion, all field wiring should be to the non-fused dis-
connect rather than the terminal blocks.
30GT080-110 and 230B-315B Units — All field power en-
ters the unit through the control box at the left end when
facing the compressors. An access hole is under the control
box. All units have a single location for power connection to
simplify the field power wiring. Maximum wire size that the
unit terminal block will accept is 500 kcmil. Unit may use
copper, copper-clad aluminum, or aluminum conductors at
all voltages, except 30GT110, 290B, and 315B 346-3-50 units
and 30GT110, 290B, and 315B 380/415-3-50 part wind units.
These units require copper conductors.
For 208/230-3-60 units, larger than 500 kcmil conductors
are required. Power must be supplied by 6 parallel conduc-
tors for these units.
LEGEND AND NOTES FOR WIRING DIAGRAMS (FIG. 11-15)
LEGEND
EQUIP — Equipment
GND
— Ground
TB
— Terminal Block
KCMIL — Thousand Circular Mils
NEC
— National Electrical Code (U.S.A.)
Field Power Wiring
Factory Installed Wiring
NOTES:
1. Factory wiring is in accordance with NEC. Field modifications or
additions must be in compliance with all applicable codes.
2. Wiring for main field power supply must be rated 75° C minimum.
Use copper, copper-clad aluminum, or aluminum conductors for
all units, except use copper conductors only for the following units:
30GT110, 290B, and 315B 346-v; 30GT110, 290B, and 315B
380/415-v part-wind start; 30GT210, 315A, 390A, 420A/B 208/
230-volts.
3. Dimensions in [
] are millimeters.
Fig. 11 — Field Power Wiring; Unit Sizes 080-110
28
