4.1.2 The
equipment used in provision refrigeration systems is to be provided
with local control and monitoring arrangements.
4.1.3 Where
isolation of equipment or systems can be carried out, means of indicating
the status of isolation is to be provided at positions where the equipment
and system can be operated and monitored.
4.1.4 Instrumentation
to indicate the operational status of running and any standby equipment
is to be provided locally and at any control station.
4.1.5 All
cooling and secondary refrigerant pumps are to be provided with an
indication of discharge pressure and a low discharge pressure alarm
at each control station.
4.1.6 The
power to all independently driven ventilation fans is to be capable
of being stopped from position(s) outside the fire boundary which
will always be readily accessible in the event of fire occurring in
any space, as well as from the local control panel.
4.1.8 Refrigeration
compressors are to be provided with the following instrumentation
and automatic shutdowns:
-
Indication of
suction pressure (saturated temperature), including intermediate stage
when applicable.
-
Indication of
discharge pressure (saturated temperature), including intermediate
stage when applicable.
-
Indication of
lubricating oil pressure.
-
Indication of
cumulative running hours.
-
Automatic shutdown
in the event of low lubricating oil pressure.
-
Automatic shutdown
in the event of high discharge pressure which is to operate at a pressure
in excess of normal operating pressure but not greater than 0,9 of
the maximum working pressure.
-
Automatic shutdown
in the event of a low suction pressure.
4.1.9 For
refrigeration compressors greater than 25 kW, the following instrumentation,
additional to that required by Vol 3, Pt 1, Ch 2, 4.1 General 4.1.8,
is to be provided:
-
Indication of
lubricating oil temperature.
-
Indication of
cooling water outlet temperature.
-
Indication of
cumulative running hours (reciprocating compressors).
-
Indication of
suction and discharge temperatures.
4.1.10 Alarms
are to be initiated in the event of the following fault conditions
with refrigeration compressors:
-
High discharge
pressure.
-
Low suction pressure.
-
Low oil pressure.
-
High discharge
temperature.
-
High oil temperature.
-
Motor shutdown.
4.1.11 Refrigeration
plants are to be provided with the following alarms as applicable:
-
Failure of condenser
cooling water pumps.
-
High condenser
cooling water outlet temperature.
-
Failure of air
cooler fans.
-
High and low
refrigerated air delivery temperatures.
-
High secondary
refrigerant temperatures.
-
Failure of secondary
refrigerant pump.
-
Low level in
secondary refrigerant header tank.