Boss’nX alarm rules: compare two KNX measurements in bulk

The Comparison trigger type on the Alarm rules page creates, in each component, an alarm that compares a source datapoint with another datapoint of the same component, identified by its tag, for example a supply temperature and a return temperature. A single operation thus covers all the components whose datapoints carry these tags.

Intended for the administrator or installer authorized to manage components. To set up a single comparison in one component, follow the comparison in a component alarm instead.

Before you start

• The measurements, units and parameters of the two datapoints allow the comparison you want.
• Both datapoints are KNX datapoints that have a read address. The source datapoint must be compatible with this mode: a boolean source datapoint is shown as incompatible.
• The selection, the limit of five hundred datapoints and the handling of partial results are described in the creation guide.

Choose the two tags and the condition

1. Open Menu → Alarm rules.
2. In the Tag field at the top, choose the tag of the source datapoints. Check the Create view.
3. In a new preparation, choose Comparison under Trigger type. If you had already filled in another type, leave and reopen this page before sending anything, to start again from a definition to check.
4. Under Compare to (tag B), choose the tag of the partner datapoints.
5. Under Operator, choose the comparison you want: greater than ( > ), greater than or equal ( >= ), less than ( < ), less than or equal ( <= ), equal ( == ) or not equal ( != ).
6. Fill in Hysteresis (tolerance) according to the planned setting; you will check its effect in the confirmation preview. If the expected condition remains ambiguous, consult support before creating the alarm.

Fictional example: compare Supply temperature and Return temperature of the same boiler, with the corresponding tags. Use the datapoints actually configured and the condition planned for your installation.

Check the pairing of each row

The partner is searched for in the same component as the source datapoint, excluding the source datapoint itself. In Measure points, expand the locations or use Expand all.

Result on a row	Action
Partner shown with its label and address	Check that it is the right datapoint. A single partner is offered automatically.
Ambiguous — pick the target:	Open the — pick — list, then select the right label and its address. The row may then become eligible and be checked automatically.
No “…” point in this component	Check tag B and the datapoints of this component: a datapoint located in another component does not qualify. This row cannot be created without a partner.
Incompatible datapoint	Check the DPT and the expected type of monitoring. Do not change the DPT to make the row artificially eligible.

Uncheck unwanted rows, even if their partner is offered automatically. The paired, ambiguous and without partner totals help you check the batch. Collapsed branches keep their selections.

Changing the source tag, tag B or the trigger type clears the manual choices of partners. Check each pairing again after such a change.

Confirm the creation

1. Check Severity and Trigger delay (min). Comparison mode shows Auto-reset once the condition is no longer true. and does not offer the Reset delay (min) field.
2. Fill in the options you want, the Alarm names and the Tag of created alarms.
3. Click Apply to selection (…). In Confirm creation, check the names, the number of components and the condition with the partner shown.
4. Use Back to correct before sending, or Confirm, then wait for Report.
5. Check the results and the rejections before clicking Close.

Check the result

Choose the tag of the created alarms and find the new datapoints in Existing alarms. Each new item is a comparison alarm datapoint: the creation adds no command to the monitored datapoints. Then test the condition on the installation.

Troubleshooting

After a partial result, check the datapoints already created and do not recreate the items already present.

For a partner that cannot be found, an uncertain condition or a persistent failure, contact support@can-nx.com with the supervision, the component, the two tags and the desired result.

French labels: Comparaison, Comparer à (tag B), Opérateur, Hystérésis (tolérance), Ambigu — choisir la cible :, — choisir —, apparié, sans partenaire.