Planning And Application; Behaviour During A Malfunction - ABB i-bus KNX Product Manual

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ABB i-bus KNX

Planning and Application

4 Planning and Application
In this section, you will find useful instructions concerning the planning and application of the Valve Drive
Actuator. Application examples and practical tips on the topic of temperature control etc. can be found in
the Application manual Heating/Ventilation/Air-Conditioning at www.abb.de/knx.
4.1

Behaviour during a malfunction

Fuse
Three outputs each (e.g. A, B, C) are internally protected in the device with a fuse. The fuse trips as soon
as a fault (short-circuit or overload) has been detected. All outputs of a group (e.g. A, B, C) are switched
off and sent a telegram with the value 1 via the communication object Overload/Short circuit by. An active
PWM control is interrupted.
Note
The response at short circuit and overload has the highest priority and deactivates an active manual
operation as well as an active safety function (forced operation or blocking) of an output in the
respective output group.
In case of a short circuit or overload the installation must be inspected and the fault remedied.
Test
After a fuse cooling time (about 25 seconds), the test of the outputs commences. For this purpose, the
outputs are switched on consecutively for about 4 seconds (LED on the output to be tested is on) and
tested for a short circuit. During the test, the red LED
performed on the outputs of a group, which are not parameterized or at which a Forced operation or
function Blocking is active. The test for the outputs of a group can take up to 60 seconds. The duration is
dependent on the temperature and the current flow in the event of a short circuit or an overload.
Reaction of the output after positive short circuit test
If the test has ended for all three outputs of a group, and at least one of the outputs has a short circuit, the
other outputs are enabled again and continue to operate normally.
The output that has the short circuit is switched off or blocked.
The bit no. 1 Short circuit in the status byte of the output or outputs concerned is set to 1.
The communication objects Overload/short circuit of the outputs not concerned send a telegram with the
value 0.
flashes slowly (SF = 1 Hz). The test is also
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