3.4 Wiring Diagrams
Single heater wiring
Most installations will be a single immerSUN connected to a single heater. This is shown in the diagram
below.
Alternative wiring method
If the immerSUN is located close to the consumer unit, it may be simpler to use the alternative wiring
option using 4-core cable or singles. As the Earth and Neutral terminals are each common, the alternative
option shows that the heater earth and neutral need not be directly connected the the immerSUN. The
alternative wiring method can also be used for all of the additional wiring options.
Using the multifunction relay
When wiring one of the options involving the relay contacts, the relay function must be selected. This is
done via the Relay Function option in the Installer Menu. See section 4.3. The relay can be set to perform
only one of the functions.
Linking several immerSUN units (Cascading)
Up to four immerSUN units can be linked together. This allows up to 12kW (3kW for each immerSUN) of
surplus power to be utilised on one phase. This is known as Cascading as the first immerSUN will
consume the first available 3kW, the second unit in the chain will then consume the next available 3kW
and so on. When using cascade mode, each immerSUN must have its own 3kW (maximum) load.
The immerSUNs should be linked in a 'daisy-chain' fashion with twisted-pair signal cable using the
COMMS terminals A and B. Cascade mode needs to be selected in the Installer Menu. See section 4.3
For simple single heater control, relay connections not required, comms connections (A&B) are used only when several immerSUN
devices are to be linked. (Also see Alternative Mains Wiring diagram).
9
240V AC MAINS SUPPLY
From 16A MCB or
13A fused outlet
IMMERSION HEATER
Max. Load 3kW
CLAMP
Install onto incoming mains
Live cable to building
Single Immersion Heater
COMMS LINK
For linking several
ImmerSUN devices
ISOLATOR
Must be double-pole
5V GD
A
B
CT CT
COMMS
RELAY
MAINS
NO
C
NC
E
E
N
L
N
LH
CLAMP
PWR
