6
3 -
HARDWARE DESCRIPTION
3.1 - General description
Each.circuit.is.by.default.fitted.with.one.SIOB.board.used.to.
manage all inputs and outputs of the controller. TCPM board
is used to control the operation of screw compressors and
AUX
1
board is used for fans control (one AUX1 per each
circuit). Options such as energy management, heat reclaim,
free cooling require additional SIOB boards to be installed.
Additionally,.chillers.fitted.with.a.dry.cooler.have.one.extra.
AUX1 board used to control the optional dry cooler.
All boards communicate via an internal LEN bus. The main
board continuously monitors the information received from
various pressure and temperature probes and accordingly
starts the program that controls the unit.
The unit is equipped with the Touch Pilot user interface (5-
inch colour LCD touch screen).
3.4 - Power supply to boards
All boards are supplied from a common 24 VAC supply
referred to earth.
CAUTION:
Maintain correct polarity when connecting the
power supply to the boards, otherwise the boards may be
damaged.
In the event of a power supply interrupt, the unit restarts
automatically without the need for an external command.
However, any faults active when the supply is interrupted
are saved and may in certain cases prevent a given circuit or
the unit from restarting.
Legend:
1. USB connector
2. Ethernet connector
3. CCN connector
4. LEN connector
5. Power supply
connector (24 VAC)
1
2
3
4
5
3.3 - Light emitting diodes on boards
Connections are located on the bottom side of the main
controller.
3.2 - Electrical box
The electrical box includes all boards controlling the unit
and the user interface.
3.5 - Light emitting diodes on boards
All boards continuously check and indicate the proper
operation of their electronic circuits. A light emitting diode
(LED) lights on each board when it is operating properly.
•.
The.red.LED.flashing.for.a.two-second.period.on.the.
SIOB board indicates correct operation. A different
rate indicates a board or a software failure.
•.
The.green.LED.flashes.continuously.on.all.boards.to.
show that the board is communicating correctly over
its.internal.bus..If.the.green.LED.is.not.flashing,.this.
indicates a LEN bus wiring problem.
