ABB i-bus KNX Product Manual page 50

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ABB i-bus KNX
Planning and Application
Reaction of the output after negative short-circuit test (no short circuit test)
If a short circuit could not be determined after the fuse trips and the three outputs are tested, after about
40 seconds the 3 outputs of a group are checked for a possible overload. A 7 day test cycle commences.
Should the fuse trip 3 times within a period of 7 days, but a short circuit is not determined on any of the
outputs, an overload is assumed. Then all 3 outputs of a group are switched off or blocked. The red LED
and the output LEDs of the output group concerned flash quickly (5 Hz). The bit no. 2 Overload in the
status byte of the output or outputs concerned is set to 1.
For all outputs of the group, the communication objects Overload/short circuit are written with a 1. In this
case, the reason for the overload, e.g. to many valve drives, must be remedied. Subsequently, on the
corresponding group of outputs, the outputs will need to be reset via the button
communication object no. 4 Reset overload/short circuit. The red LED
normal operation, and the LEDs indicate the respective status.
If a fault does not re-occur within a 7 day period, the test cycle is automatically reset. The communication
objects Overload/short circuit and bit no. 2 in the status byte of the output or outputs concerned is set to 0.
X
FF
48 2CDC 508 101 D0201 | VAA/S x.230.2.1
Y Z
X-Z
Remark
FF FF On Overload detected. All outputs of the group concerned are blocked or switched off.
FF = Fast flashing (5 Hz). SF = Slow flashing (1 Hz):
or via the device
goes off. The outputs operate in