Intesis
TM
Modbus Server - KNX
User Manual r1.2 eng
© HMS Industrial Networks S.L.U - All rights reserved
This information is subject to change without notice
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KNX interface
In this section, a common description for all Intesis KNX series gateways is given from the point of view of KNX
system, which is called from now on
external system.
The Modbus system is also called from now on
internal system
.
Description
Intesis KNX interface connects directly to the KNX TP-1 bus and performs as any another device in the KNX system,
with the same configuration and operational characteristics as other KNX devices.
Internally, the circuit part connected to the KNX bus is opto-isolated from the rest of the electronics.
Intesis KNX interface receives, manages and sends all the telegrams related to its configuration to the KNX bus.
On receiving WRITE telegrams of KNX Group Addresses associated to internal datapoints, the corresponding
messages are sent to the internal system (Modbus) to maintain both systems synchronised in every moment.
When a change in a signal of the external system is detected, a WRITE telegram is sent to the KNX bus (addressed
with the Group Address associated to the corresponding Group Object), in order to maintain both systems
synchronised at every moment.
The status of the KNX bus is checked continuously and, if a bus drop-down is detected, for example due to a failure
in the bus power supply, after the KNX bus is restored again, Intesis will send READ telegrams on all group objects
marked with
"Ri"
. The behaviour of each individual point into Intesis is determined by the flags configured for the
point. See details in section 2.2.
Points definition
Every internal datapoint to define has the following KNX properties:
Property
Description
Description
Descriptive information about the Communication Object or Signal.
Signal
Signal's Description. Only for informative purposes, allows identifying the signal
comfortably.
DPT
It is the KNX data type used to code the signal's value. It will depend on the type of
signal associated in the external system in every case. In some integrations, it is
selectable, in others it is fixed due to the intrinsic characteristics of the signal.
Group
It is the KNX group to which the point is associated. It is also the group to which the
read (R), write (W), transmit (T), update (U) and read on init (Ri) flags are applied. It is
the sending group.
Listening
addresses
They are the addresses that can write on the group object, apart of the main group
address.
R
Read. If this flag is activated, READ telegrams of this group address will be accepted.
Ri
Read on Init. If this flag is activated, the object will trigger corresponding READ request
(on associated group address) on initialization.
W
Write. If this flag is activated, WRITE telegrams on this group object will be accepted.
T
Transmit. If this flag is activated, when the group object value changes, due to a change
in the external system, a WRITE telegram of the associated group address will be sent
to the KNX bus.
U
Update. If this flag is activated, UPDATE telegrams (response to READ telegrams) on
this group object will be accepted.
Active
If activated, the point will be active in Intesis, if not, the behaviour will be as if the point
is not defined. This allows deactivating points without the need of delete them for
possible future use.