ABB SA/S 12.16.6.1 Product Manual - Knx Commissioning
ABB i-bus
®
KNX Commissioning
98 2CDC 505 056 D0207 | SA/S
• only with a closed contact: An undershoot or overshoot of the set
current threshold is only evaluated when the contact is closed.
As a result, by a contact opened via the KNX (current flow
interrupted), a current threshold undershoot (as error) is never
detected. Precondition for the correct evaluation is that the
contact is closed via a switch action via the KNX. Manual
switching is not recognised, the current threshold is not
interrupted. Thus manual switching is interpreted as a circuit-
breaker or load fault. The evaluation occurs in accordance with
the time set in parameter Evaluation delay (0...255s) after contact
closing.
• only with an opened contact: An undershoot or overshoot of the
set current threshold is only evaluated when the contact is
opened.
In this way, for example, you can immediately detect when a
switched off contact is inadmissibly switched on manually.
Evaluation occurs about one second after opening the contact.
The time is fixed for system reasons and cannot be influenced.
The monitoring occurs not just once after a contact change, but
rather continuously (about once a second).
How does evaluation function?
The detection of the current value occurs in accordance with
the parameterised contact position. Should a different contact
position than parameterised be the case on the output of the
SA/S, the current value is not detected and not evaluated.
Furthermore, the current value is also not recorded during the
parameterised evaluation delay, whereby a comparison with
the setpoint is also not undertaken during this period. After
completion of the evaluation delay, the present current value is
recorded and compared with the current threshold.
The status of the current threshold is only sent if there is a
change in the status in comparison to the previous status value.
When only with a closed contact is selected, the current is only
detected with a closed contact, compared to the current
threshold and sent on a change. When the contact is open,
there is no current detection and thus no evaluation. A
prerequisite is that the contact is opened by a switching
telegram initiated via the KNX. Manual switching will not be
detected.
In this case, the SA/S assumes that there is an open circuit or a
fault on the load. The current detection continues; the detected
current value is compared to the current threshold and sent on
a status change.