The Controls; Connections At The User's Terminal Block - Carrier 30RQ Operation And Maintenance Instructions

3.5 - The controls

evaporator pumps
The controller can regulate one or two evaporator pumps
and takes care of automatic change-over between pumps.
evaporator heater
It protects the evaporator (and the pipe heater for units
without pump) against freezing if the unit is off.
Boiler
This relay output authorises start/stop of a boiler.
Cooling units
Description
Evaporator pump 1 control
Evaporator pump 2 control
Evaporator heater control
Alarm relay output
Alert relay output
Operation or ready-to-start relay
output
Contact 1:
Start/stop
Contact 2:
Setpoint selection
Contact 3:
Demand limit selection 1
Contact 3 bis:
Demand limit selection 2
User safety loop input
Contact 4:
Heat reclaim selection
Contact 4:
Free cooling prevention
Contact 5:
Pump operation status
Connection to CCN
Critical alarm relay output
Connector/ Terminal Board
channel
J2A / CH19 PD5-BASE
J2A / CH20 PD5-BASE
J2B / CH21 PD5-BASE
J3 / CH24 PD5-BASE
J3 / CH25 PD5-BASE
J3 / CH26 PD5-BASE
J4 / CH11 32-33 PD5-BASE
J4 / CH12 65-66 PD5-BASE
J4 / CH13 63-64 PD5-BASE
CH9 NRCP2-BASE This contact is only present if the energy management option is used.
J4 / CH15a 34-35 PD5-BASE
J4 / CH14 PD5-BASE
J4 / CH14 PD5-BASE
J5C / CH18 PD5-BASE
J12 PD5-BASE
J2C / CH23 PD5-BASE

3.6 - Connections at the user's terminal block

3.6.1 - General description
The contacts below are available at the user's terminal block
on the PD5-BASE board (see figure 1). Some of them can
only be used if the unit operates in remote operating type
(rEM). The following table summarises the connections at
the user's terminal block.
Remarks
The control can regulate one or two evaporator pumps, and automatically change over
between the two pumps.
The control can regulate one or two evaporator pumps, and automatically change over
between the two pumps.
This (and the pipe heater for units without pumps) protects the evaporator against frost.
Indicates alarms.
Indicates alerts.
Indicates if the unit is ready to start or operates.
This contact is used for unit start/stop. It is only taken into account if the unit is under
remote operation control (rEM).
This contact is only taken into account if the unit is under remote operation control (rEM).
See the description of these contacts in sections 3.6.5 and 3.6.6.
This contact is mounted in series with the water flow control contact. It can be used for
any customer safety loop that requires that the unit is stopped, if it is open. If it is unused
this contact must be bridged.
This contact is used to select the heat reclaim mode.This contact is only used, if the heat
reclaim option is used (not compatible with the free cooling option).
If this contact is closed, it is used to prevent operation of the free cooling mode. It is only
taken into account, if the unit is under remote operation control (rEM). This contact is only
used if the free cooling option is used (incompatible with the heat reclaim option).
If this contact is open, the pump is controlled and an alarm has tripped.
An RS-485 bus is used for connection to the CCN.
- Pin 1: signal +
- Pin 2: ground
- Pin 3: signal -
Output allows disconnecting the general unit power supply, if a contactor is stuck and
there is an increased risk of the unit being damaged.
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