ABB i-bus KNX Product Manual page 12

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ABB i-bus KNX
Device technology
Note
Current values less than 25 mA are indicated as a 0 mA value on the KNX (starting current). For small
load currents that are just above the minimum detection threshold of 25 mA, it is possible that a value of
0 mA is displayed due to the inaccuracies, even though a current is flowing.
The Energy Actuator is only suitable for recording measured values of Loads, i.e., the meters only
record positive energy. Negative power values are discarded with load control, and negative instrument
and power values (feedback) cannot be monitored with thresholds.
Important
Threshold value monitoring should not be used for safety-relevant applications. The Energy Actuator
cannot assume the function of a circuit-breaker or RCD (earth-leakage circuit breaker).
With communication objects that can be written via the bus (e.g. threshold value limits), the range of
values is not limited, i.e. even if the values that can be entered in the ETS for a threshold value or load
limit can only be entered within defined limits, any value can be written to the communication object
over the bus. It is therefore necessary to ensure that only permitted and useful values can be written to
the communication object.
If the threshold value monitoring is to be used for equipment fault detection that only causes a slight
change of less than 30 mA (7 W), mains voltage and current fluctuations due to ambient influences (e.g.
temperature) and natural ageing of the load play a significant role. Even when the current changes are
detected by the Energy Actuator, the detected current changes do not necessarily mean that a device
has failed.
The outputs are electrically isolated from each other, i.e. they can be connected to different phase
conductors within the voltage ranges permitted in the technical data. There may not be potential differ-
ences between the neutral conductor connection of the load and the neutral conductor connection on
the Energy Actuator to ensure that useful measured values are delivered.
(Also refer to the note under
In order to avoid dangerous touch voltages, which originate through feedback from different phase
conductors, all-pole disconnection must be observed when extending or modifying the electrical connec-
tions.
10 2CDC 505 084 D0203 | SE/S 3.16.1
Circuit diagram, page 11.)
Danger