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8
3.9 - Connections at the user terminal block
Connections available at the user terminal block may vary
depending on the selected options.
Terminal block connections
Description
Board
Input/Output
Connector
Remarks
On/Off switch
SIOB, circuit A
DI-01
J1
Used for the unit on/off control if the unit is in Remote mode
Second setpoint switch
SIOB, circuit A
DI-02
J1
The contact is taken into consideration if the unit is in Remote mode
Demand limit switch 1
SIOB, circuit A
DI-03
J1
Used to control demand limit. See section 7.7
Heat cool select status
SIOB, circuit A
DI-04
J1
Used to select heat cool mode
Condenser flow status (30XW only)
SIOB, circuit A
DI-08
J1
Used to control the condenser status
Setpoint reset control
SIOB, circuit A
AI-10
J9
Allows the customer to reset the currently selected setpoint
Alarm relay
SIOB, circuit A
DO-05
J23
Indicates alarms
Running relay
SIOB, circuit A
DO-06
J22
Indicates if the unit is ready to start or operating
Optional
Occupancy override
SIOB, EMM
DI-01
J1
Enables to switch between occupied (closed contact) and
unoccupied mode (open contact)
Demand limit switch 2
SIOB, EMM
DI-02
J1
Used to control demand limit. See section 7.7
Customer interlock
SIOB, EMM
DI-03
J1
Used for the customer safety loops
Ice done contact
SIOB, EMM
DI-04
J1
Used to control the setpoint according to the occupancy schedule
Capacity limit control
SIOB, EMM
AI-10
J9
Used for capacity limitation
Chiller partially shutdown
SIOB, EMM
DO-05
J23
Indicates the shutdown of one of the circuits
Chiller shutdown
SIOB, EMM
DO-06
J22
Indicates the unit shutdown
Chiller capacity running output (0 to 10 V)
SIOB, EMM
AO-01
J10
Reports the capacity percentage of the unit
Heat reclaim condenser flow status (30XA only)
SIOB, Heat reclaim DI-01
J1
Used to verify the water flow on the condenser side
Heat reclaim enable switch (30XA only)
SIOB, Heat reclaim DI-02
J1
Used to switch between air-condenser (open contact) and water
condenser (closed contact) in Remote mode
Free cooling disable switch (30XA only)
SIOB, Free cooling DI-01
J1
Used to control free cooling when the unit is in Remote mode
3.9.2 - Volt-free contact on/off/cooling/heating
If the unit operates in Remote mode, on/off contacts and
heating/cooling contacts operate as follows:
Without multiplexing
Off
Cooling
Heating
On/Off contact
open
closed
closed
Cooling/heating contact
-
open
closed
With multiplexing
Off
Cooling
Heating
Auto
On/Off contact
open
closed
closed
open
Cooling/heating contact
open
open
closed
closed
Legend:
1. Off: Unit is stopped
2. Cooling: Unit is allowed to start in Cooling
3. Heating: Unit is allowed to start in Heating
4. Auto: Unit can run in Cooling or Heating in accordance with the changeover
values.
3.9.3 - Volt-free setpoint selection contact
This dry contact input is used to switch between setpoints. It
is active only when the control is in Remote mode.
Cooling
Heating
Setpoint 1 Setpoint 2 Setpoint 1 Setpoint 2
Setpoint selection contact open
closed
open
closed
3.9.1 - General description
Some contacts can be accessed only when the unit operates
in Remote mode.
The following table summarises the connections at the user
terminal block.
3.9.4 - Volt-free demand limit selection contact
Up to two dry contacts can be used to limit unit capacity.
Note that the second contact is available for units with the
energy management module.
Capacity limitation with two contacts is as follows:
100%
Limit 1
Limit 2
Limit 3
Demand limit 1 contact
open
closed
open
closed
Demand limit 2 contact
open
open
closed
closed
The limits are defined in the SETPOINT menu.