Table of Contents
Advertisement
5.8
CAN-BUS
The various circuit boards in the heat pump and hwdu
are connected by a CAN-BUS communications cable.
CAN (Controller Area Network) is a two-wire system for
communication between microprocessor based
modules/circuit boards, which are connected in series.
The Greensource outdoor unit holds the PCB - IOB
board, all other pcbs are located in the indoor HWDU.
CAUTION: Interference.
B The CAN-BUS cable must be screened
and laid separately from the power cable.
A suitable cable for the external connection is a CAT 5
E FTP 2x2x0.5A. The cable must be multi-core and
screened. The screen may only be earthed at one end
and only at the casing.
The cable may be up to 20 m long.
Fig. 4
Switch S1 highlights the beginning and end of the CAN-
BUS cable. This means that the CPU board in the internal
unit and the IOB board in the heat pump must be
terminated by S1. For this, set S1 to Term.
6 720 641 467 (2010/01)
For latest prices and delivery to your door visit MyTub Ltd - www.mytub.co.uk - info@mytub.co.uk 0844 556 1818
CAN-BUS cable must not be laid alongside power supply
cables. Minimum distance 100 mm between cables.
They may be laid alongside sensor cables.
Ensure that the external CAN- BUS cables when routed
into the hwdu are not in connect with the mains cable.
CAUTION: Do not mix up the 12V and CAN-
BUS connections!
The processors are destroyed if 12V is
connected to the CAN-BUS.
B Check that the four cables are connected
to the contacts with the corresponding
marking on the circuit board.
The connection between the circuit boards is by four
wires, because the 12V-supply between the circuit
boards must also be connected. The circuit boards have
markings for both the 12V and CAN-BUS connections.
GENERAL
6 720 0614 056-03.1D
9
Advertisement
Table of Contents
