IOM SYSCREW AIR EVO HSE

22
6 - Control
6.1 General information
Introduction
This document contains the information and the operating instructions
for 2 screw compressors (step type and inverter driven type).
This information is for the after-sales service and the production
operators, for the end-of-line testing.
Main characteristics
– Microprocessor control
– User-friendly keyboard
– Proportional and integral control of the return water temperature
or leaving water temperature (LWT or RWT)
– Access code to enter the Service Level
– Access code to enter User Level
– Basic functions without access code
– Alarm and LED
– Backlighted LCD
– Rotation of the compressor operation
– Oil return function - Standard for the inverter compressor,
optional (oil switch device) for step compressor
– Night mode (or Low Noise) control
– Counting of the pump/compressors’ hours of operation
– Display of discharge and suction pressure values
– Display of temperature sensor
– History of stored alarms (option)
– Built-in serial communication RS485 port with Modbus protocol
to connect the main board to a BMS network.
This built-in port is available as standard only in the case no
extra network control systems (netTune) are selected with the
units.
– Built-in serial communication Ethernet port with two possible
protocols (Modbus or Bacnet, in case also at the same time). In
case of Bacnet communication protocol it is needed to activate a
license.
– Custom protocols are available on request
The following accessories can be also connected:
– Remote Display Terminal.
The control system consists of:
a) Main Board. The units are provided with a microprocessor card
which is fully programmed by default for the control of a chiller
of cold only type with 2 circuits, 1 compressor for circuit, a HP
transducer and a LP transducer for Circuit.
b) EEV controllers (two separate drivers) for the management of the
electronic expansion valves.
C) Keyboard & Display Terminal.
The terminal makes it possible to carry out the following operations:
– the change of the main operating parameters
– the display of the detected alarms
– the display of all the measured quantities
The terminal and the card are connected by a 6-way phone cable.
The connection of the terminal to the basic card is not essential for
the normal operation of the controller.