Principles of Construction
Electrical wiring diagrams are mounted inside the units.
Remove the cover to refer. Units are built to IP.44 standards.
The dual voltage (110/240v) version can be wired internally at
a reduced capacity of 1.5kw on 110 volts.
To alter the supply on the dual voltage unit, 110v to 240v, or
vice versa, refer to the wiring diagram.
Remember to rotate the supply identification plate on the top of
the unit to match the appropriate wiring configuration for the
dual voltage unit. Connecting the wrong supply to the unit can
damage components and as such is not classed as a warranty
fault.
No neutral wire is required for the 415/3/50 units. Just 3
phases and earth wires.
The units are all supplied with carrying handles on the top
cover.
The top cover consists of the sides and top and is held in place
by screws along the bottom of the sides. These screws are
most easily removed using a socket spanner.
The remainder of the "fixings" in the unit are rivets. Although
we acknowledge this makes the exchange of parts potentially
more difficult, as compared with the use of screws or bolts,
experience has shown that any such exchanges are intermittent
that the advantages of not having screws coming loose and/or
them "seizing" over long periods, more than outweighs any
disadvantage.
Plugs and Cables
Plugs and sockets have to be carefully selected to suit the
capacity and voltage of the unit.
The bare ends of the cable supplied with the heater are tinned.
This is appropriate for connection into large terminal blocks. For
smaller terminals, remove the length of tinning, leaving a short
length of bare strands.
Recommended Plugs
Hot Block 25
240 Volt
13 Amp 3 Pin Plug
16 Amp 2 Pole + E Industrial Plug
Hot Block 25
110 Volt
32 Amp 2 Pole + E Industrial Plug
Hot Block 65
415 Volt
32 Amp 3 Pole + E Industrial Plug
Hot Block 95
415 Volt
32 Amp 3 Pole + E Industrial Plug
The Hot Block 25 on a 110 volt supply requires a minimum of
3kVA continuously rated transformer power. Any less
transformer power reduce the heat output by reference to the
wiring diagram inside the unit.
For extended runs of supply cable, in excess of the cable
supplied with the unit, the following schedule will allow for a
maximum volt drop at the unit of 10 volts on maximum heat
setting:-
Hot Block 25
110 Volt
0 to 20 metres
2.50mm² cables
25 to 40 metres
4.00mm² cables
Hot Block 25
240 Volt
0 to 50 metres
2.50mm² cables
50 to 100 metres
4.00mm² cables
Hot Block 65
415 Volt
0 to 50 metres
2.50mm² cables
50 to 75 metres
4.00mm² cables
75 to 100 metres
6.00mm² cables
Hot Block 95
415 Volt
0 to 50 metres
4.00mm² cables
50 to 75 metres
6.00mm² cables
At the unit a voltage drop of more than 15% below the normal
supply rating will cause damage to the heater.