Operating instructions

EC3 Series
Coldroom Controllers
D A T A S H E E T
EC3-3_35041_EN_R13.docx 5 / 8 23.02.2012
Alarm and Maintenance Functions
EC3-33x provides many alarm codes to facilitate diagnosis.
Limit violation alarms are associated with temperature and
pressure set point (high alarm, low alarm, sensor failure).
The serial alarm loop of the compressor can be connected to a
digital input. It will monitor compressor operation and signal
shutdown in case the serial alarm loop is open due to high
motor temperature or excessive pressure etc.
Alarm management includes the issuing of an alarm message
through the network and to show the alarm code on the
controllers display. The priorities and subsequent actions can
be individually defined for each alarm when connected to a PC
or an AMS monitoring server.
The EC3-332 has the capability to send alarm messages
directly by email.
While the attached Display Unit ECD-001 indicates alarms as
blinking symbols only, the monitoring WebPage shows all
alarms in text form. All possible alarm messages are visible,
active alarms are highlighted bold, see below:
Safety Functions
Various safety functions are available for use particularly when
the EC3-33x is controlling the compressor directly. These safety
features are used to prevent compressor damage and include:
Limitation of maximum evaporating pressure (MOP), delay of
compressor start after control reset, minimum time between two
starts, minimum compressor off time, minimum compressor run
time.
Safe operating modes allow the system to continue to operate
safely even when the signal is lost from a defective or
disconnected sensor.
Particularly useful facilities are the service functions, which
enable the engineer to manually control the system during
commissioning. They include manual operation of compressor,
fan and Electrical Control Valve, or special operating modes of
system for cleaning, permanent night operation, manual defrost
or others, see below:
In event of power failure to the entire system, the stepper motor
driven valve would not be able to move. Due to the differential
pressure between condenser and evaporator, the refrigerant
could continue to flow through the valve if the valve is open.
The compressor must be protected after power recovery
against wet running. EC3-33x contains an internal rechargeable
battery and smart battery charge control to automatically close
the valve in case of power failure. Whilst the battery is
maintenance free, the life expectancy will depend upon the
working ambient; as the temperature increases the life
expectancy reduces.
It is recommended to replace the battery annually to maintain
the system in optimum operating condition.
If the alarm relay is not utilized, the user must ensure
appropriate safety precautions are in place to protect the
system against damage caused by a power failure.
Wiring Diagram
EC3-33x Coldroom Controller for Electrical Control Valves EX4 … EX8
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