3 - HARDWARE DESCRIPTION
3.7 Terminal block connections
Connections available at the user terminal block may vary
depending on the selected options. The following table summarizes
connections at the user terminal block.
IMPORTANT: Some contacts can be accessed only when
the unit operates in Remote mode.
Description
Board
Connector
Remarks
On/Off Switch
SIOB
DI-01, 32-33
Used for the unit on/off control (Remote mode only):
open = unit is Off
closed = heating allowed
Setpoint Switch
SIOB
DI-02, 65-66
When the unit is under remote control, the volt-free contact is used to determine the
active setpoint (see section 7.5.1):
open = heating setpoint 1 is used
closed = heating setpoint 2 is used
Limit Switch
SIOB
DI-03, 73-74
Used to control demand limit:
open = 100% capacity can be used, no demand limitation is applied
closed = demand limitation applied (see section 7.3)
Flow Switch / Interlock Switch
SIOB
DI-05, 34-35
Used to control the pump and unit operation:
open = pump continues to run
closed = pump is stopped (unit is not allowed to start)
DHW Tank Request Switch
SIOB
DI-06, 63-64
Used to command the domestic hot water loop in case of DHW option:
open = DHW disabled
closed = DHW allowed
Running Relay
SIOB
DO-05, 37-38
Used to signal a running status (at least one compressor start)
Alarm Relay
SIOB
DO-06, 30-31
Used to signal an alarm:
open = inactive (no alarms active)
closed = alarm(s) active
Electrical Heat Stage #1 or Boiler
AUX1
DO-01, 51-52
Used to control the electrical heater stage 1 or boiler:
open = electrical heater or boiler not active
closed = electrical heater or boiler active
Electrical Heat Stage #2
AUX1
DO-02, 53-54
Used to control the electrical heater stage 2:
open = output inactive, closed = output active
Electrical Heat Stage #3
AUX1
DO-03, 55-56
Used to control the electrical heater stage 3:
open = output inactive, closed = output active
Electrical Heat Stage #4
AUX1
DO-04, 57-58
Used to control the electrical heater stage 4:
open = output inactive, closed = output active
Terminal block connections
AQUACIAT
CALEO
EN - 4
