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4. Features of the system
18
Connecting other compressors
Compressors from other manufacturers can be
connected to the GD Connect 12 via compressor
modules:
Compressor module (STD)
Compressors with fixed speed or half/full load
control can be connected with this module.
Compressor module (VSD)
Compressors with speed regulation can be
connected with this module.
Further information on the modules can be found in
chapter 6 "Compressor module (STD)" and chapter 7
"Compressor module (VSD)" respectively.
Programmable inputs and outputs
The GD Connect 12 has
3 digital inputs (DI-1..3)
2 digital outputs (DO-1..2)
These are routed to the terminal strip and can be
assigned to various functions.
Further information on programming can be found in the
description of the "Settings" menu in section 5.7.
ModBus-RTU / PROFIBUS interface
A separate RS485 interface is provided for customer
use to read the current operating status of the GD
Connect 12 (RS485-3).
The ModBus-RTU protocol is implemented as standard.
Details of the protocol and the addresses can be found
in a separate document ("GD Connect 12 Programmer
guide ModBus-RTU").
To enable the GD Connect 12 to be connected to a
PROFIBUS network, an optional PROFIBUS module
can be installed in the GD Connect 12 control cabinet.
For the PROFIBUS module too, details of the protocol
and the addresses can be found in a separate
document ("GD Connect 12 Programmer guide
PROFIBUS").
Extension modules
An extension module is used to expand the number of
programmable inputs and outputs of the GD Connect
12.
The RS485-2 interface of the GD Connect 12 can
connect a maximum of 4 extension modules.
The extension modules are available in two versions
which differ only in terms of their power supply:
Version 1: 230V AC / 50-60Hz
Version 2: 110V AC / 50-60Hz
An extension module adds
8 digital inputs (DI-1..8)
2 digital outputs (DO-1..2)
2 analog inputs (AI-1..2)
to the GD Connect 12.
Further information can be found in chapter 8
"Extension modules".