M970-07/04
PAGE 15
10. Electrical Supplies / Connections.
Ensure local supply line, wall socket or break-out box is available for correct rating of
supply to be used. (3 phase 190 V. 5 kW. – 110 V. per phase, star with neutral and
earth / ground connection OR single phase 110 V. 5 kW. 42 amp)
Using 3-phase supply
Connect 3 phase star n ground (5 wire) cable rated at 20 amps per line
with neutral and ground rated at 35 amps. from laboratory / plant supply box through
furnace control unit cable entry to the 3 phase circuit breaker input, neutral bus-bar and
ground (earth) connections in the furnace control unit.
If a 3 phase supply previously requested, a cable will be supplied and wired at factory
from furnace control unit cable entry for connection to local supply box.
Using single phase supply.
Connect single phase (Line, Neutral and ground / earth) 3 wire cable rated at 50 amps
per line from local supply box through furnace control unit cable entry. Connect 2 wire
line and neutral leads to 2 inputs on circuit breaker and ground (earth) wire to earth bus-
bar terminals.
If single phase supply not previously requested it is necessary to change input power
connection in furnace control unit as follows :-
(A) Connect 3 “Line” supply terminals (R, Y, B on drawing appendix 2) together using
the copper bus-bar strip provided.
(B) Disconnect L2 to Y lead and using 50 amp cable link provided, connect L2 to the
Neutral 1, 2 and 3 bus-bar terminals.
