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industrial heat tracing solutions
EN-RaychemNGC30UIT2Programming-AR-H5818602/16
3.3.9 SETUP | PASC WINDOW
This window configures the PASC setup if the PASC control mode is selected for a Circuit.
Fig. 3.15 Setup | PASC window
Min Ambient Temp Entry Field
The Min Ambient Temp is the “lowest ambient temperature” that was used when the heat-tracing
system was designed. The entered value should agree with the value used by the design
engineer to ensure that the heating-tracing system was sized correctly.
Range Raychem NGC-20: –73°C (–99°F) to 51°C (124°F)
Range Raychem NGC-30: –73°C (–99°F) to 51°C (125°F)
Default: –40°C (–40°F)
Min Pipe Size Entry List
Min. Pipe Size is the diameter of the smallest heat-traced pipe in the group controlled by this
Circuit. Small diameter pipes heat up and cool down more rapidly than larger diameter pipe.
Therefore, the PASC duty cycle is calculated over a shorter time base. Larger diameter pipes heat
and cool less rapidly, so the on/off periods for the heater system can be stretched over a longer
period. If electromechanical contactors are being used to control the heater circuit, the longer
time base reduces the number of contactor on/off cycles and extends the contactor life.
List: 0.5, 1, >= 2 inches
Default: 0.5 inches
Power Adjust Entry Field
This allows the PASC control to be adjusted when the heating cable output is greater than the
design assumption, or if the pipe insulation proves to be more efficient than assumed. Pipe
temperature may run higher or lower than desired if the heating cable has a different output than
required to offset the heat loss. The Power Adjust parameter enables a reduction or an increase in
the heat-tracing effective power by entering a value less or greater than 100%
IMPORTANT: If improperly used, the Power Adjust parameter can cause the piping to get too
cold or too hot. If unsure, leave at 100%. Do not change this value unless an engineer calculates
the temperature impact on the system and determines that it is safe to do so. Be particularly
cautious if the circuit has more than one diameter of pipe or type of heat tracing. Contact a Pentair
Industrial Heat Tracing Solutions representative for assistance with this factor.
Range: 10–200%
Default: 100%
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