750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
8-5
8.5 — Electrical Controls
FIGURE 8-1. Recommended Maximum “Fusetron” Fuse Sizes
Thermal relay units (overloads) are of the melting-alloy type and, when tripped, the alloy must be given time to re-
solidify before relay can be reset. IF the overloads trip out repeatedly when the motor current is normal, replace
them with new overloads. If the condition continues after replacement, it will be necessary to determine the cause
of excessive current draw at the overloads.
Power supply to the boiler must be protected with dual element fuses (fusetrons) or circuit breakers. Similar fuses
should be used in branch circuits. Standard one-shot fuses are not recommended. Refer to the chart in Figure 8-2
for fuse requirement guidance.