Devices And Solutions For Protection; Passive Safety Devices; Active Safety Devices; Protection Systems - Rivacold CO2NNEXT Instrucciones Para El Ensamblaje

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Devices and Solutions for Protection

2.2.1. Passive Safety Devices

The devices and construction solutions described below have been adopted for the partly
completed machinery:
 fixed guards protecting moving parts;
 outer enclosure with fixed access doors;
 safety signs on the guards of the partly completed machinery.

2.2.2. Active Safety Devices

The active safety devices described below have been adopted for the partly completed
machinery:
 HPB maximum pressure switch;
 The units are classified in risk category PED = 1 so they are not equipped with a fusible plug
or a pressure relief valve on the liquid receiver.
CAUTION: It is strictly prohibited to alter the setting of safety pressure switch HBP.

2.2.3. Protection systems

The system is equipped with protections to safeguard against anomalous situations on the pressure
circuit and on the power circuit.
Overpressure in the refrigerant circuit
Delivery line refrigerant overpressure, which, apart from impairing system operation, can be
hazardous for personnel, is regulated by means of a protection with two trip levels:
 When the pressure reaches values in excess of the acceptable conditions, said values being
established on the basis of the characteristics of the refrigerant adopted, the sizing of the
system, and the compressor characteristics, the maximum pressure switches trip to stop the
associated compressor. Normal operation of the system can be restored automatically or
after a manual reset, to be carried out only after the cause of the overpressure conditions
has been eliminated. The reset procedures vary in accordance with the characteristics of
the machine.
CAUTION: It is strictly prohibited to change the calibration of the safety high pressure
switch after the associated commissioning test has been carried out.
 With regard to all the pressure relief valves on the low pressure and high pressure sides of the
circuit, the related pressure setting is shown on the valve itself and has been calculated in
compliance with the prescriptions of EN 13136.
Tripping of these devices causes release of all or some of the refrigerant charge in the
circuit.
Refrigerant pressure fault
Defective refrigerant pressure, incorrect adjustment of the thermostatic valves, and gas leaks
causing a reduction in refrigerant charge are all potential causes that can lower the suction
pressure below the permissible design values.
This situation is not hazardous for operators, but it causes a drastic reduction in the thermodynamic
efficiency of the system and can give rise to compressor breakage.
Co2Nnext
EN
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