Power Supply Installation
Place your PR power supply in a well-ventilated location. Note: The unit will generate heat as
it operates, especially if used at or near its current output limits.
WARNING!: Hazardous voltages are present inside the unit. DO NOT expose the
unit to rain or moisture. PR models should only be used in a dry, indoor, protected
Place your equipment next to your PR model power supply.
CAUTION!: DO NOT block the louvers on PR models. Allow at least 2" above the
top of the PR cabinet for ventilation. The compact, space-saving design of the PR
has been made possible by careful placement of the cabinet louvers and design
of the external heat sinks, to provide adequate internal cooling for long life and
There are two DC power output terminals on the rear of PR power supplies: POSITIVE (+)/ RED,
and NEGATIVE (-)/ BLACK. With all equipment turned OFF, connect the DC equipment to
these terminals, making sure to observe the polarity of the wiring. Connect Positive to Positive
(red to red), and Negative to Negative (black to black).
Power Supply Start-Up
Plug the power line cord into a 120 V AC, 60 Hz. outlet. Depress the “ON/OFF” switch on the front
panel. The switch body (or indicator light on smaller models) will illuminate RED, indicating
the power supply is functioning properly. Turn the connected DC equipment ON only after the
power supply has been turned ON.
Tripp Lite PR series’ power supply current ratings are based on the industry-standard ICS
(Intermittent Communications Service), limited by heat buildup. This translates to a 50% duty
cycle of 5 minutes ON, 5 minutes OFF. Equivalent heat loading would result from 7 minutes
ON at 25% load, followed by 3 minutes ON at 100% load. This cyclical-type of loading is similar
to the operation of a transceiver.
Make sure the equipment you are using is properly sized to the capacity of the power supply.
The maximum current draw of the equipment should not exceed the continuous-duty output of
the power supply. If unsure about your particular application or current output capacities, call
Tripp Lite Customer Service at (773) 869-1234.
The PR series features electronic foldback current limiting, which protects against short circuits
on the DC output. The foldback circuitry reduces the output current to less than one amp when restored.
When the overload is removed, normal current and voltage outputs are automatically restored.
CAUTION!: Electronic foldback current limiting will NOT overcome severe or sustained
overloads. Some loads may demand peak current more than twice as high as
their average current demand. This fact should be kept in mind when using the
PR series power supplies.