3.2 Electrical Connections
Electrical connections should be made only by a competent person. Do not attempt to install this
unit if you are not a qualified or an experienced electrician. Installation may involve alterations to
fixed wiring and opening the consumer unit, there is risk of death by electrocution.
Choose the most suitable cable entry points (rear or bottom) and make the electrical connections to the
unit according to the appropriate wiring diagram (see section 3.4). Use the blanking plugs provided for
unused cable entry points.
Alternative loads
In some cases it may be desired to control the power to a load other than an immersion heater. The load
MUST be a simple resistive load, e.g. an electric towel radiator, storage heater etc.
The load must not exceed 3.2kW and must not include digital or analogue timers, as they may be
damaged by the proportional output control of the immerSUN.
IMPORTANT!
Be sure to fully tighten terminals, checking the cables are securely clamped by the terminals and the cord
grips. Failure to ensure good connection could result in fire or permanent damage to the unit.
NOTE:
The screw terminals are 'rising clamp' type.
TERMINALS
MAINS
L
LIVE FEED
240V supply input, should be from 16A MCB or 13A fused outlet
LH
LIVE OUTPUT
Live output to immersion heater, maximum load 13A or 3kW
N
NEUTRAL (x2)
Mains Neutral terminals (All Neutral terminals are internally connected)
E
EARTH (x2)
Mains Earth terminals (All Earth terminals are internally connected)
IMPORTANT!
Earth MUST be connected
RELAY
(used for some additional functions, see wiring diagrams in section 3.4)
NO
NORMALLY OPEN
Volt-free normally open relay contact (max. current 13A)
C
COMMON
Volt-free common relay contact (max. current 13A)
NC
NORMALLY CLOSED
Volt-free normally closed relay contact (max. current 13A)
CLAMP
CT
CURRENT TRANSFORMER
AC current transformer clamp terminals
COMMUNICATIONS
A
RS485 A
RS485 communication terminal A (D+)
B
RS485 B
RS485 communication terminal B (D-)
GD
DIGITAL GND
Ground connection for future use
5V
5V OUTPUT
5-volt output connection for future use
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