Specifications

28
JOHNSON CONTROLS
Form 201.28-NM1.EN.PED/CE (0211)
INSTALLATION
REFRIGERANT RELIEF VALVE PIPING
The evaporator is protected against internal refrigerant
overpressure by refrigerant relief valves. A pressure
relief valve is mounted on each of the main refrigerant
lines connecting the cooler to the compressors.
A piece of pipe is fitted to each valve and directed so that
when the valve is activated the release of high pressure
gas and liquid cannot be a danger or cause injury. For
indoor installations (not recommended), pressure relief
valves should be piped to the exterior of the building.
The size of any piping attached to a relief valve must
be of sufficient diameter so as not to cause resistance to
the operation of the valve. Unless otherwise specified by
local regulations. Internal diameter depends on the length
of pipe required and is given by the following formula:
D
5
= 1.447 x L
• Where:
• D = minimum pipe internal diameter in cm
• L = length of pipe in meters
If relief piping is common to more than one valve, its
cross-sectional area must be at least the total required
by each valve. Valve types should not be mixed on a
common pipe. Precautions should be taken to ensure the
outlets of relief valves or relief valve vent pipes remain
clear of obstructions at all times.
ELECTRICAL CONNECTION
The following connection recommendations are intended
to ensure safe and satisfactory operation of the unit.
Failure to follow these recommendations could cause
harm to persons or damage the unit, and may invalidate
the warranty.
No additional controls (relays, etc.) should
be mounted in the control panel. Power and
control wiring not connected to the control
panel should not be run through the control
panel. If these precautions are not followed
it could lead to a risk of electrocution. In
addition, electrical noise could cause
malfunctions or damage the unit and its
controls.
After power wiring connection, do not
switch on mains power to the unit. Some
internal components are live when the
mains are switched on and this must only
be done by “Authorized” persons familiar
with starting, operating, and troubleshooting
this type of equipment.
POWER WIRING
All electrical wiring should be carried out in accordance
with local regulations. Route properly sized cables to
cable entries on the unit.
In accordance with local codes, NEC codes, U.L. and
C.E. standards, it is the responsibility of the user to install
over current protection devices between the supply
conductors and the power supply terminals on the unit.
To ensure that no eddy currents are set up in the power
panel, the cables forming the 3-phase power supply must
enter via the same cable entry.
All sources of supply to the unit must be
taken via a common point of isolation (not
supplied by Johnson Controls).
POWER SUPPLY WIRING
Units require only one 3-phase supply, plus earth.
Connect the 3-phase supplies to the circuit breaker
located in the panel (See Electrical Lug Data).
Connect a suitably sized earth wire to the PE terminal in
the panel.
115VAC CONTROL SUPPLY TRANSFORMER
A 3-wire high voltage to 115VAC supply transformer
is standard in the chiller. This transformer is mounted
in the cabinet and steps down the high voltage supply
to 115VAC to be used by the controls, VSD, Feed and
Drain Valve Controller, valves, solenoids, heaters, etc.
The high voltage for the transformer primary is taken
from the chiller input. Fusing is provided for the
transformer.
Removing high voltage power to the chiller
will remove the 115VAC supply voltage to
the control panel circuitry and the
evaporator heater. In cold weather, this
could cause serious damage to the chiller
due to evaporator freeze-up. Do not remove
power unless alternate means are taken to
ensure operation of the evaporator heater.