POSITIVE TEMPERATURE COEFFICIENT (PTC2) HEATER MANUAL
PTC2 Heater Systems are manufactured and distributed by Waukesha
®
Service & Components, a division of SPX Transformer Solutions, Inc.
PTC2-Manual Rev. 1.3, 04/2013
2
GENERAL DESCRIPTION
The Waukesha
®
Positive Temperature Coefficient (PTC2) Heater improves the reliability of your electrical
equipment by maintaining an enclosure temperature slightly higher than the outside ambient temperature.
The system offers unparalleled reliability due to the elimination of a thermostat or other controls. In addition,
standard PTC2 convection heaters utilize an integrated fan assembly that ensures even heat distribution
throughout the enclosure.
CONSTRUCTION
PTC2 heaters feature a heating element constructed with a variable resistance material that automatically
reacts to the cabinet (inlet air) temperature. A fan (if equipped) is attached to the heat guard and provides
forced conduction of the heat as well as uniform enclosure distribution. Mounting brackets allow easy
cabinet or panel installation. A twelve-foot wiring harness (on forced air units) is also included to make
installation as easy and flexible as possible.
OPTIONS
PTC2 heaters are available in the following configurations:
20 Watt:
120V or 240V (dual voltage) panel mount convection
30 Watt:
120V or 240V (dual voltage) panel mount convection
40 Watt:
120V or 240V (dual voltage) panel mount convection
60 Watt:
120V or 240V (dual voltage) panel mount convection
200 Watt:
120V or 240V fan forced with or without activating thermostat
300 Watt:
120V or 240V fan forced with or without activating thermostat
400 Watt:
120V or 240V fan forced with or without activating thermostat
200 Watt:
120V or 240V fan forced, Thermostat activated
300 Watt:
120V or 240V fan forced, Thermostat activated
400 Watt:
120V or 240V fan forced, Thermostat activated
200 Watt Constant/400 Watt High Recovery:
Thermostat actuated, 120V or 240V fan forced
300 Watt Constant/400 Watt High Recovery:
Thermostat actuated, 120V or 240V fan forced
SELECTION
Several factors should be considered when selecting the appropriate heater. Primary concerns should
include the following:
Ambient temperature extremes—affects which part of the wattage curve is used to select the heater.
Rate of ambient temperature change—affects how much time a given wattage requires to return to
steady state.
Enclosure size, insulation rating and exposure to ambient conditions.
For anti-condensation purposes, heaters should be selected according to the calculated power required
(watts) to warm the enclosure to a
minimum
temperature difference of 5 degrees Celsius above ambient.
