Carbolite MTT 12/38/850 - Manual (Page 13)

MTT
MF38 – 3.07
13
8.0 F USES & P OWER S ETTINGS
8.1 Fuses
Supply fuses (F1 in circuit diagram) - 12.5A glass type F 32mm x 6mm
Control circuit fuses (F2 in circuit diagram) - 5A glass type F 20mm x 5mm
Note: the internal supply fuses are rate at 12.5A although the maximum power of the furnace is
rated at 13A. Because of power control the 12.5A fuses should be adequate. Should these fuses
blow, then 16A may be substituted. Should 16A fuses blow, there is a circuit fault.
Fuse Replacement
Access to internal fuses is by removal of the back panel of the base (control box). Fuses are
mounted on an EMC filter unit which has the appearance of a circuit board.
Customer Fuses
The supply should be fused at 13A, 15A or 16A. All of these are safe fuse levels and the choice
depends on the country or environment in which the equipment is installed.
8.2 Power Limit
The furnace is designed to run on supplies of voltage 220V to 240V at the same power. This is
achieved by use of the Power Limit (
OP.Hi ) parameter in the controllers, which is set to the
following values:
Voltage Power limit OP.Hi
220V 100
230V 92
240V 83
Do not increase the parameter over the appropriate value as given above: a fuse may blow, or, in
the worst instance, the heating element could burn out.