Roberts Gorden COMBAT CTU 22 TO 115 - Manual (Page 21)

SECTION 10: W IRING AND E LECTRICAL I NFORMATION
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SECTION 10: WIRING AND ELECTRICAL INFORMATION
10.1 Electrical Supply
All heaters need a constant 230 V 50 Hz single
phase supply connected to terminals L, N & Earth.
Polarity "L & N" must be correct. The voltage
between neutral and earth should be 0 and never
exceed 15 volts.
All heaters and controls must be correctly earthed.
All external wiring must comply with the relevant
local codes. Wire specification H05VV-F.
External controls must have the same constant
230 V 50 Hz supply.
An isolator with a contact separation of at least
3 mm on all poles must be installed adjacent to, but
not attached to, the heater to disconnect all supplies
to the heater and any remote control.
The final connection to the heater should be made
by flexible cable or conduit to the main terminal
block on the inside of the heater using 1 mm
2 cable
on all models.
Models ............................................ Fuse Size
CTUA (All Models) ........................................... 5 A
CTUB & CTUC (Models 22-50)...................... 10 A
CTUB & CTUC (Models 75 - 115) .................. 20 A
CTUD heaters must have the external fan, or its
control connected to Terminal 1 so that the fan run-
on function at close down operates correctly.
WARNING
Electrical Shock Hazard
Disconnect electrical power before servicing.
Failure to follow these instructions can result in
death or electrical shock.
10.2 Remote Controls
The heater is designed to be operated by controls
installed remote from the heater.
See Page 16,
Section 10.3. through Page 17, Section 10.4.
10.2.1 Burner Controls (Thermostat)
Controls to operate the burner must be voltage free
contacts connected between terminals 2 & 3 of the
main terminal block.
10.2.2 Positioning Room Thermostats or
ROBERTS GORDON ® Control
A room thermostat or ROBERTS GORDON ®
control should be mounted on a wall or column at a
height of approximately 1.5 metres from the floor to
measure the ambient temperature. It should be clear
of both cold draughts and the direct path of warm air
from the heater.
10.2.3 Remote Frost Thermostat
When required, connect to terminals 2 and 3 in the
main terminal block.
Locate within the heated space adjacent to the most
vulnerable equipment that requires protection.
See Page 16, Section 10.3 through Page 17, Section
10.4.
10.2.4 Remote Fan Controls
The fan will operate automatically providing there is
a constant 230 V supply to the main terminals.
A switch or control wired between terminals L & 1 in
the terminal block will allow external control of the
fan(s).
The fan may be controlled to operate continuously
from an external control, with the burner cycling on
and off, providing that the fan run-on at close down
is not impaired.