York R-407C Optimized, Manual, Page: 115 / 120

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YORK INTERNATIONAL
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YORK INTERNATIONAL
FORM 201.19-EG4
out of range, remote input indication, chilled liquid
reset setpoint, leaving liquid pull-down rate setpoint,
leaving liquid error (deviation from setpoint), and
history data for last six shutdown faults. Com-
pressor suction, discharge, and oil pressures and
temperatures, suction and discharge superheats,
percent of full-load motor current, operating hours,
starts, and anti-recycle timer status. Status Mes-
sages for manual over-ride, unit switch off, com-
pressor run, run permissive, remote controlled shut
down, no cooling load, daily/holiday shut down,
anti-recycle/anti-coincident timer, high pressure
low suction temperature limit.
7. System Safeties: Shall cause individual compressor
systems to perform auto-reset shut down; manual
reset required after the third trip in 90 minutes.
Includes: high discharge pressure or temperature,
low suction pressure, high / low motor current, high
pressure switch, high / low differential oil pressure,
high oil temperature, and motor protector. Com-
pressor motor protector shall protect against dam-
age due to: low or high input current, phase reversal
(reverse rotation), current unbalance, phase loss,
thermal overload of windings, and low voltage.
8. Unit Safeties: Shall be automatic reset and cause
compressors to shut down if: high or low ambient,
low leaving chilled liquid temperature, under volt-
age, and flow switch operation. Contractor shall
provide flow switch and wiring per chiller manufac-
turer requirements.
9. Alarm Contacts: High or low ambient, low leaving
chilled liquid temperature, low voltage, low battery,
and (per compressor circuit): high discharge pres-
sure or temperature, low suction pressure, low or
high motor current, low or high differential oil pres-
sure, and high oil temperature.
E. Manufacturer shall provide any controls not listed
above, necessary for automatic chiller operation.
Mechanical Contractor shall provide field control
wiring necessary to interface sensors to the chiller
control system.
2.06 POWER CONNECTION AND
DISTRIBUTION
A. POWER PANELS:
1. NEMA 3R/12 (IP55) rain/dust tight, powder painted
steel cabinets with hinged, latched, and gasket
sealed outer doors equipped with wind struts for
safer servicing. Provide main power connection(s),
compressor and fan motor start contactors, current
overloads, and factory wiring.
2. Field power supply wiring connections shall be to a
single power center on the chiller, shall be 3 phase
of scheduled voltage, and shall connect to terminal
blocks per each of the two motor control panels.
Separate disconnecting means and/or external
branch circuit protection (by Contractor) required
per applicable local or national codes.
3. Provide two electrically separate, adjacent motor
control center cabinets, with independent doors and
separated by a steel panel, for compressor and fan
motor power distribution components.
B. Exposed compressor and fan motor power wiring
shall be routed through liquid tight conduit.
2.07 ACCESSORIES AND OPTIONS
Some accessories and options supercede standard
product features. Your YORK representative will be
pleased to provide assistance.
A. Microprocessor controlled, Factory installed Wye-
Delta compressor motor starters for reduced
compressor inrush start current. Machines equipped
with single-point power connection and with Star-
Delta compressor motor start shall also include Fac-
tory provided circuit breakers in each motor control
center.
B. Power Supply Connections:
1. Multiple Point Supply with Individual Systems Cir-
cuit Breakers or Non-Fused Disconnect Switches:
Two Field provided branch circuits shall connect to
individual system Circuit Breakers or Non-Fused
Disconnects per compressor on each of the two
motor control centers, with lockable external
handles on doors in compliance with Article 440-
14 of the N.E.C.
2. Single Point Terminal Block or Non-fused Dis-
connect Switch: Field provided branch circuit
shall connect to single-point Terminal Block or
Non-Fused Disconnect with lockable external
handle in compliance with N.E.C. Article 440-14,
with Factory provided interconnecting wiring to
(optional Individual System Circuit Breakers, and)
compressor motor start components in each of
two motor control center cabinets.
3. Single Point Circuit Breaker: Field provided
branch circuit shall connect to single-point Circuit
Breaker with Lockable External Handle (in com-
pliance with Article 440-14 of N.E.C.). Factory
provided interconnecting wiring to compressor
motor start components in each of two motor
control center cabinets.
C. Control Circuit Power Terminal Strip (115V, 1
∅)
lo-