If the Heating Elements of the Trough Heaters are similar to Heat Trace Cable (i.e.: Self-Regulated Heater Cable), using a Class A GFCI (Trip Threshold = 6ma) would result in repeated Trip Issues under normal / correct operation.
In the case of Heat Trace Cables, instead of using the Class A, 6ma Trip Threshold GFCI Devices for controlling excessive "Leakage", Ground Fault Protection for Equipment ("GFPE") Devices are used. The standard Trip Threshold for these GFPE Devices = 30ma (0.03A).
GFPE Branch Circuit Breakers look exactly the same as GFCI Branch Circuit Breakers, only the Catalog Numbers differ...
Example:
GE's THQB 240VAC Class 10KAIC 1 pole 20 Amp GFCI (5ma) Breakers are Product Number "THQB1120GF", whereas the THQB 240VAC Class 10KAIC 1 pole 20 Amp GFPE (30ma) Breakers are Product Number "THQB1120GFEP".
Both look exactly the same, except when viewing the Billing Statements from the Wholesale House;...
the GFPE Device is at least 2x the cost of its GFCI counterpart!!!
--Scott (EE)
