Nibe S1256PC Installer Manual page 22

NOTE
When several heat pumps are connected together,
an external supply temperature sensor (BT25) and
an external return line sensor (BT71) must be used.
Connect the communication cables between the heat pumps
in series to terminal block X30:1 (GND), X30:2 (+12V), X30:3
(B) and X30:4 (A) on the base board (AA2).
The example shows the connection of several S1256PC .
Main unit Heat pump 2
Huvudenhet Värmepump 2
1 2 3 4 1
AA2-X30 AA2-X30
Connecting accessories
Instructions for connecting accessories are provided in the
manual accompanying the accessory. See section "Accessor-
ies" for a list of the accessories that can be used with
S1256PC. Connection for communication with the most
common accessories is shown here.
Accessories with accessory board (AA5)
Accessories with accessory board (AA5) connect to terminal
block AA2-X30:1, 3, 4 in S1256PC.
If several accessories are to be connected, or are already
installed, the boards are connected in series.
Because there can be different connections for accessories
with accessory board (AA5), you should always read the in-
structions in the manual for the accessory that is to be in-
stalled.
22 Chapter 5 | Electrical connections
Heat pump 3
Värmepump 3
2 3 4 1 2 3 4
AA2-X30
S1256PC
AA2-X30
1 2 3 4
Accessory 1
AA5-X4
1 A
2 B
GND
3
4 A
5 B
6 GND
7
8
Accessory 2
AA5-X4
1 A
2 B
3 GND
4 A
5 B
6 GND
7
8
Network cable for myUplink (W130)
In instances when you want to connect to myUplink using
a network cable instead of via wifi.
1. Connect the shielded network cable to the display.
2. Route the network cable to the top of S1256PC.
3. Follow the flow meter's cable out at the rear.
SELECTABLE OUTPUTS/INPUTS
S1256PC has software-controlled AUX inputs and outputs
for connecting the external switch function (contact has to
be potential-free) or sensor.
In menu 7.4 - "Selectable in/outputs", you select the AUX
connection to which each function has been connected.
For certain functions, accessories may be required.
NIBE S1256PC