York YCUL0045E, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
15
FORM 150.63-NM8 (1020)
1
DISCHARGE AIR SENSOR
The discharge air sensor and associated connector
hardware is factory supplied but must be field installed.
Field wire must be field supplied (QUABBIN 930421-
2 or equivalent 2 conductor with shield and drain wire
- 20 AWG 300 V 60°C - polyethylene insulation UV
resistant). Field wiring is connected to pins 8, 5, and
2 of J6 on the I/O Board.
Refer to Figure 9 and unit
wiring diagram.
ZONE TERMOSTATS
Field supplied thermostats or dry contacts must be field
wired when operating the unit in Suction Pressure
Control Mode
. The System 1 zone thermostat is field
wired at CTB1 terminals 13 to 14. On two system units
(YCUL0125 - YCUL0275) System 2 zone thermostat is
field wired to CTB1 terminals 13 to 16. CTB 1 terminal
is located near the bottom of the micro control panel.
Refer to Figure 6 and unit wiring diagram.
See Air Proving Switch/Remote Start-Stop
Contacts.
Suction Pressure control cannot be used unless the
optional suction transducers are installed on the unit
(standard on YCUL0211 - YCUL0275).
SUCTION TEMPERATURE SENSORS (OPTIONAL)
This is a field installed option that provides individual
displays of suction line temperature for each system at
the condensing unit. This option performs no control
function, but simply provides the suction line tem-
perature for each refrigerant system as measured at the
condensing unit.
On the I/O Board, the connections are field wired to J8,
pins 8, 5, & 2 for System 1; J10 pins 8, 5 & 2 for System
2. Refer to Figure 10 and unit wiring diagram.
The sensors should be attached to the suction line with
copper straps, and heat conducting compound should
be used to ensure good heat transfer. Sensors should
be mounted at the 4 or 8 o'clock positions.
Air Proving Switch/Remote Start-Stop Contacts
The air proving switch is field wired to CTB1 terminals
13 to 14 (sys 1) and 13 to 16 (sys 2) to prevent operation
of the refrigerant circuit when the supply air blower is
not operating.
If separate evaporator blowers are used with respect to
each refrigerant system in the condensing unit, then two
air proving switches must be wired in series across CTB1
terminals 13 - 14 and 13 - 16 (one for each evaporator
blower).
Refer to Figure 6 and unit wiring diagram.
When using Zone Thermostats in Suction Pressure con-
trol mode, the air proving switch(s) should be wired in
series with the respective Zone Thermostats.
Remote Start/Stop Contacts
To remotely start and stop the condensing unit, dry con-
tacts can be wired in series with the air proving switch
and CTB1 - terminals 13 to 14 (sys 1) and 13 to 16 (sys
2). Refer to Figure 6 and unit wiring diagram.
Remote Emergency Cutoff
Immediate shutdown of the condensing unit can be
accomplished by opening a field installed dry contact
to break the electrical circuit between terminals 5 to L
on terminal block CTB2.CTB2 is located in the power
PANEL. THE unit is shipped with a factory jumper in-
stalled between terminals 5 to L, which must be removed
if emergency shutdown contacts are installed.
Refer to
Figure 7 and unit wiring diagram.
Evaporator Blower Start Contacts
For constant fan operation: Terminal block CTB2 - ter-
minals 23 to 24, are normally open dry contacts that can
be used to switch field supplied power to provide a start
signal to the evaporator blower contactor.
Refer to Figure 7 and unit wiring diagram .
Compressor Run Contacts
Contacts are available to monitor “Compressor Run”
status. Normally-open auxiliary dry contacts from each
compressor contactor are wired in parallel with CTB2
- terminals 25 to 26 for system 1, and CTB2 - terminals
27 to 28 for system 2 (YCUL0125 - YCUL0275).
Refer to Figure 7 and unit wiring diagram.
Alarm Status Contacts
Normally-open contacts are available for each refriger-
ant system. These normally-open contacts close when
the system is functioning normally. The respective con-
tacts will open when the unit is shut down on a unit fault,
or locked out on a system fault. Field connections are at
CTB2 terminals 29 to 30 (sys 1), and terminals 31 to 32
(sys 2).
Refer to Figure 7 and unit wiring diagram
.