York YLPA 0115SE, Инструкция по установке, эксплуатации и обслуживанию

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JOHNSON CONTROLS
FORM 150.68-ICOM1
ISSUE DATE: 10/15/2020
RUN CONTACTS
Terminals 25 and 26 close to indicate that refrigerant
system 1 is running and terminals 27 and 28 close to
indicate that refrigerant system 2 is running.
ALARM CONTACTS
Each refrigerant system has a voltage-free normally
open contact that will close when control power is
applied to the panel, if no fault conditions are present.
When a fault occurs which locks a system out, or there
is a power failure the contact opens. To obtain a system
alarm signal, connect the alarm circuit to terminals 29
and 30 for No. 1 system and terminals 31 and 32 for
No. 2 system.
CONTROL WIRING - SYSTEM INPUTS
All wiring to the control terminal block (nominal 30
VDC) must be run in screened cable, with the screen
earthed at the panel end only. Run screened cable
separately from mains cable to avoid electrical noise
pick-up.
The voltage free contacts must be suitable for 30 VDC
(gold contacts recommended). If the voltage free
contacts form part of a relay or contactor, the coil of
the device must be suppressed using a standard RC
suppressor. The above precautions must be taken to
avoid electrical noise that could cause a malfunction or
damage to the unit and its controls.
FLOW SWITCH
A chilled liquid flow switch of suitable type must be
connected to terminals 13 and 14 to provide adequate
protection against loss of liquid flow.
REMOTE START/STOP
Connect a remote switch to terminals 13 and 51 to
provide remote start/stop control if required.
REMOTE MODE SELECTION
Remote mode selection can be accomplished by
connecting a contact between terminals 13 and 50. With
the contact open the unit is in the cooling mode, with the
contact closed the unit is in the heating mode.
REMOTE RESET OF CHILLED LIQUID
SETPOINT
The PWM input (terminals 13 and 20) allows reset of
the chilled liquid setpoint by supplying a ‘timed’ contact
closure.
REMOTE LOAD LIMITING
Load limiting prevents the unit from loading beyond
a desired value. The unit % load limit depends on the
number of compressors on the unit. The load limit inputs
to terminals 13 and 21 work in conjunction with the
PWM input to terminals 13 and 20.
FAN FULL SPEED INHIBIT
To reduce unit noise, the fans can be limited to run at a
maximum step of all fans in star (reduced speed), that is
fan full speed is inhibited. Connect a customer voltage
free contact to terminals 13 & 15.
EMS ANALOGUE INPUT
Provides a means of resetting the leaving chilled or hot
liquid temperature from the BAS/EMS. Accepts 4 to
20 mA, 0 to 20 mA, 0 to 10 VDC or 2-10 VDC. Connect
to terminal A+ and A-.
MODBUS, BACNET MS/TP AND N2
Enable communications with building protocol systems
using Modbus, BACnet or N2 protocol. Connect through
standard RS485 port.