Tubular element with mounted thermal fuse
Most of Backer’s heating elements can be equipped with a thermal fuse. This design offers a major advantage when compared to a separately mounted thermal cut-off.
Elements with dia. 8.5 or 14 mm can be equipped with a replaceable thermal fuse. The silicone rubber bushing containing a thermal fuse is pulled out from the element with a suitable tool. A new unit is then easily mounted.
In elements with permanently mounted fuse the thermal fuse is moulded with compound at the sealing operation and is not replaceable. When the thermal fuse has tripped, the element must be replaced.
Cut off temperature
To establish correct cut-off temperature, measurements have to be done under normal condition. The cut-off temperature is recommended to be at least 25-30°C above the maximum temperature of the thermal fuse at normal operation.
With permanently mounted thermal fuses normal flat pin connectors can be used. As an alternative connection cables can be spot welded directly on the terminal pin. Round pin connectors are preferred when replacable thermal fuses are used.
Heating elements with mounted thermal fuse are approved
Meet requirements per EN 60335-1
Electrical heat protection and thermal fuse
66, 72, 91, 98, 109, 128, 14, 152, 184, 216, 228°C
Ø 6,4 mm
Ø 8,5 mm
Ø 14 mm/2
Ø 14 mm/3
Examples of applications