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A dirt trap or medium filter is installed in the medium circuit which is to be cleaned regularly,
or exchanged depending on the degree of contamination of the medium.
Option: Automatic water feed
A floating switch connected to the customer-sided mains water supply automatically feeds
water into the medium tank as soon as the water level sinks.
Option: Flow monitor
In order to be able to protect the customer-sided machine or the customer´s application 2
monitoring systems are required. One is to monitor the temperature, which takes place
through the regulator and one to monitor the flow. If the customer does not monitor the
machine or his application himself, then a flow monitor can be fitted in the refrigeration unit
return flow, which issues a signal when there is no flow or less than a minimum threshold
amount. There are flow monitors with display and without display. The signal can serve as
a warning or activate a switch-off. Generally this option is combined with under & over-
temperature messages.
Option: Accumulative error message center
All error messages flow together into the error message center where a signal is given out.
The contact is potential-free. The accumumative error message center contains not only
the unit´s-own safety facilities but also the customer-relevant monitoring facilities. Details
can be sourced from the circuit diagram.
8.2
Safety facilities
The high pressure switch protects the refrigeration unit against unnecessary high operating
pressure in the cooling agent circuit. In case of malfunction the HP switch switches the
refrigeration unit off for a minimum of 4 minutes.
The mains isolation device serves the manual switching off of the unit in case of
emergency. In some cases the refrigeration unit has to be switched off by the
user/operator.
8.3
Monitoring facilities
Thelow pressure switch protects the refrigeration unit against unnecessary low operating
pressure in the cooling agent circuit. In case of malfunction the LP switch switches the
refrigeration unit off for a minimum of 4 minutes.
The winter pressure regulator prevents low pressure malfunctions in case of low
surrounding temperatures in the unit´s run-up phase until normal operating conditions have
been established.
The overheating protection at the compressor ensures that the refrigeration unit is switched
off in cases of increased motor current. The refrigeration unit switches on again after the
compressor has cooled down.
The overheating protection at the ventilator ensures that die refrigeration unit is switched off
in cases of increased motor current. The unit switches on again after cooling down.
Summary of Contents for Typ BR 058-31
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