Robur GAHP Line AR Series, Инструкция по установке, эксплуатации и обслуживанию

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GAHP-AR – Installation, start-up, use and maintenance manual
58
Edition: 2014-08
4.5 USE OF THE DIRECT DIGITAL CONTROLLER (DDC)
This paragraph illustrates the operations to be performed when one or more
appliances are connected to a Direct Digital Controller (DDC). For specific
information regarding the DDC, refer to the specific manuals supplied with it.
The appliance and the DDC communicate with each other via a CAN bus network.
The CAN bus network is characterized by a series of elements (appliances or DDCs)
called nodes, connected to each other by a three-wire cable. The nodes are of two types:
terminal nodes and intermediate nodes.
- Terminal nodes are appliances or DDCs that are connected to one other element only.
- Intermediate nodes are appliances or DDCs that are connected to two other elements.
Figure 23 - Examples of CAN bus with: a) 2 nodes = 1 app 1 DDC; b) 3 nodes = 2 appl 1 DDC
The diagram illustrates 2 cases of connection on a CAN BUS network:
a) 1 appliance is connected to 1 DDC. The two elements, appliance and DDC, are
terminal nodes of the network, as they are each connected to one other element only.
b) 2 appliances are connected to each other and to 1 DDC. Appliance "B" and the DDC
are terminal nodes, while appliance "A" is an intermediate node as it is connected to 2
elements, which are appliance "B" and the DDC.
It is possible to place one DDC at any point of the CAN bus network: appliances and
DDCs may act equally as terminal or intermediate nodes.
One DDC can control and monitor up to 16 appliances. If there are more than 16
appliances on the network, it is necessary to connect more than one DDC on the
same network, up to a maximum of 3.
The CAN bus cable
The CAN bus cable must meet the Honeywell SDS standard.
The following table gives details of some types of CAN bus cable, grouped according to
the maximum distance covered by each single type.
CAN BUS CABLE
(available as ACCESSORY,
see SECTION 6, page 81).
2
DDC
1
st
SEGMENT OF CAN BUS
CABLE
(available as ACCESSORY,
see SECTION 6, page 81).
2
DDC
2
nd
SEGMENT OF CAN
BUS CABLE
(available as
ACCESSORY, see
SECTION 6, page 81).
a) b)
A
GAHP-AR
1
B
GAHP-AR
3
A
GAHP-AR
1