Pfannenberg PWS Series - Manual (Page 9)

6
SECTION 5: OPERATING CONDITIONS
5.1 Requirements
Before connecting the cooling unit to the power
supply, verify that the following are correct.
Voltage must be within ± 10% of the value listed on
the ID plate.
Voltage frequency must be within ± 3 Hz of the value
listed on the ID plate
Ambient temperature must be below +55ºC (for
options see Section 6.5)
Make sure that the airflow inside of the electrical
panel enclosure is not restricted by internal
components.
WA R N I N G !
If the cooling unit is being mounted on the door of
the electrical panel enclosure, it must be confirmed
that the door hinges can support the additional
weight of the cooling unit and that the electrical
panel enclosure is securely fastened so that the
panel enclosure will not topple over.
5.2 Theory of Operation
The cooling units are available in two options:
A.) With Water (solenoid) Valve and Thermostat
B.) Without Water Valve and Thermostat
A.) With Water (solenoid) Valve and Thermostat
∞
1 Water Valve (solenoid)
2 Heat Exchanger (condensor)
3 Fan
4 Thermostat with Temperature Sensor
The water valve (1) controls if water is allowed to
flow through the cooling unit.
As the water flows through the heat exchanger (2)
it absorbs the heat from air in the electrical panel
enclosure while also dehumidifying it. This process
lowers the temperature of the air in the electrical
panel enclosure.
This is accomplished by the fan (3) pulling in the hot
air from the electrical panel enclosure and pushing
it through the heat exchanger (2) and back into the
electrical panel enclosure at a lower temperature.
The cooling unit (with water valve and thermostat)
is electronically controlled. To accomplish this a
temperature sensor monitors the temperature inside
the electrical panel enclosure and regulates the
function of the water valve.
B.) Without Water Valve and Thermostat
∞
1 Water Inlet
2 Heat Exchanger (condensor)
3 Fan
The flow of water through the unit is regulated by a
control system provided by the user outside of the
coolling unit.
As the water flows through the heat exchanger (2)
it absorbs the heat from air in the electrical panel
enclosure while also dehumidifying it. This process
lowers the temperature of the air in the electrical
panel enclosure.
This is accomplished by the fan (3) pulling in the hot
air from the electrical panel enclosure and pushing
it through the heat exchanger (2) and back into the
electrical panel enclosure at a lower temperature.