Table of Contents
Advertisement
6 - OPERATION
6.3 - Safety functions
Compressor protection device
CARRIER industrial heat pumps are equipped with a protection
device for the screw compressor as standard. The protection
device is installed in the compressor terminal box.
Safety monitoring by the compressor protection device:
■ Temperature monitoring
The compressor protection device locks out as soon as the
highest permissible motor or oil temperature is exceeded.
■ Rotational direction monitoring
The compressor protection device monitors the rotational
direction in the first 5 seconds after the compressor has started.
If the compressor starts in the wrong direction, the protection
device locks out immediately. In addition, CARRIER uses a
second, upstream rotational direction monitor, which prevents
the compressor starting in the wrong direction in advance.
■ Phase failure monitoring
In the event of a phase failure within the first 5 seconds after
the compressor has started, the protection device immediately
opens the relay contact in the safety chain and closes it again
after 6 minutes. It fully locks out after 3 phase failures inside
18 minutes or after 10 phase failures within 24 hours.
16
Further safety equipment:
■ Motor overload relay for the compressor
■ Motor overload relay for the required source pump
■ Motor overload relay for the required condenser pump
■ High and low pressure controller
■ High and low pressure sensors
■ Hot gas temperature monitor
■ Frost protection monitor
■ Differential pressure switch at the evaporator
■ Flow switch for the evaporator is optionally available and is
recommended by CARRIER for low evaporator inlet
temperatures.
■ Differential pressure switch for filter in the oil circuit
Safety valve:
A safety valve discharge pipe must discharge the refrigerant to
the ambient air or to removal devices in a suitable manner or direct
it into absorbent material available in an adequate amount. The
refrigerant must not be directed into adjacent rooms, stairwells or
similar. The refrigerant must not be brought into contact with an
air supply for combustion engines, boilers or air compressors.
If for improved service quality a sealed ball shut-off valve is fitted
upstream of the safety valve on the condenser, note the following:
as soon as the valve service has been completed, the ball shut-off
valve must be checked while in the open position and sealed by
a qualified inspection body in accordance with the Pressure
Equipment Directive 2014/68/EU.
Advertisement
Table of Contents
