Downloads: Technical Bulletin 029 - Latching of Non-Latched"

Summary: The non-latched function on the ZXSe control panel cannot be used to provide a non-latched function using the event logic.

Systems affected: This affects ZxSe networks of panels using V855 firmware or higher where the “non-latched” event type has been used together with “event logic” to combine non-latching events. An example has been seen where a user has created a function that is intended to update when the input conditions change without the need for reset to restore outputs to quiescent status.

Issue Identifi ed: Event logic can be used to create inter-dependencies of multiple inputs. If these events are transmitted across a network the output of the event logic conditions will remain active when conditions are met until the system is reset.
Non-latching events were introduced in version 855, this details a limitation to their use.

Recommended Action This is a limitation of the use of event logic that will not be rectifi ed with updated fi rmware. Other ways to create non-latching conditions with multiple dependencies may be used, including using physical interfaces to link output and inputs as separate events.

Please contact Technical Support for further advice on +44 (0) 845 528 0464.