Nibe S1255-12, Installer Manual, Page: 25 / 92

TIP
The AXC accessory is required if more than
one function is to be connected to the AUX
output.
Optional functions for external connection:
Indications
• alarm indication
• indication of common alarm
• cooling mode indication (only applies if there are
cooling accessories)
• holiday indication
• away mode for "smart home" (complement to the
functions in menu 5.3)
Control
• control of circulation pump for hot water circulation
• control of external circulation pump (for heating medi-
um)
NOTE
The relevant distribution box must be marked
with a warning about external voltage.
Connecting external circulation pump
An external circulation pump is connected to the AUX
output, as illustrated below.
S1255 External
1
2
3 NO
C
NC
AA2-X27
L N PE
L
N
PE
Settings
ELECTRICAL ADDITION - MAXIMUM OUTPUT
Number of steps, maximum electrical output and supply
on connection for the immersion heater varies depend-
ing on model. See tables.
The electric additional heat may be restricted depending
on the selected country.
The immersion heater's power is split into steps (four
steps, if the immersion heater for 3x400 V is switched
to maximum 9 kW), according to table.
Setting maximum output in the electric additional heat
is done in menu 7.1.5.1.
Power steps of the immersion heater
The tables display the total phase current for the immer-
sion heater at start up. If an immersion heater has
already been started, and is not being used to its full
capacity, the values in the table can be changed because
the control initially uses this immersion heater.
Switching to maximum electrical output
If more than the maximum power (7 kW) for the immer-
sion heater connected on delivery is needed, the heat
pump can be switched to maximum 9 kW.
Move white cable from terminal block X7-2:N to terminal
block X9:L(2) on the PCB (AA2).
3x400 V (maximum electrical power, connected on
delivery 7 kW) for S1255-12 / -16)
Max phase
current
L3(A)
Max phase
current L2(A)
Max phase
current L1(A)
Max electric-
al addition
(kW)
– – – 0
4.3 – – 1
– 8.7 – 2
4.3 8.7 – 3
8.7 8.7 – 4
13.0 8.7 – 5
8.7 8.7 8.7 6
13.0 8.7 8.7 7 1
1
Factory setting
3x400 V (maximum electrical power, switched to
9 kW) for S1255-12 / -16.)
Max phase
current
L3(A)
Max phase
current L2(A)
Max phase
current L1(A)
Max electric-
al addition
(kW)
– – – 0
– 8.7 – 2
8.7 8.7 – 4
8.7 8.7 8.7 6
15.6 15.6 8.7 9
25 Chapter 5 | Electrical connections NIBE S1255