The cMT3108XP Event Display cannot natively record alarms with millisecond resolution. For a sequence-of-events application, capture the event timestamp in the SEL Axion 2240 PLC, transfer that value to the HMI, and associate it with the alarm through EasyBuilder Pro's Event Alarm Log and Multi-Watch features.
Define the Timestamp Boundary
The tested configuration uses a cMT3108XP HMI with EasyBuilder Pro V6.09.02.651 and communication to an SEL Axion 2240 PLC. The tag map imports successfully and communication is established, but the Event Display object does not provide millisecond alarm recording.
| Function | Assigned device or feature |
|---|---|
| Capture the event with millisecond precision | PLC, if its event-recording capability supports that precision |
| Transfer the captured timestamp | Mapped PLC-to-HMI value |
| Save the value with the alarm | Event Alarm Log and Multi-Watch |
| Present the event list | HMI using the transferred value |
Configure the PLC-to-HMI Data Path
- Configure the alarm and event-capture logic in the PLC.
- Confirm that the PLC can record the required events with millisecond precision.
- Expose the captured millisecond timestamp as a value that EasyBuilder Pro can read.
- Map the Multi-Watch address to the corresponding PLC address.
- Configure the Event Alarm Log to save the watched value with the alarm.
- Set the alarm-message display syntax so it inserts the transferred value correctly.
This architecture uses the PLC as the timestamp authority. It does not make the cMT3108XP Event Display a millisecond-resolution recorder; the HMI stores and displays a value captured elsewhere.
Verify Sequence-of-Events Operation
Test the configuration while connected to the PLC. Trigger known events, confirm that the mapped watch value changes, verify that the Event Alarm Log saves the value with each alarm, and check that the displayed message reproduces the PLC timestamp correctly. If milliseconds are missing or incorrect, inspect the PLC source value, address mapping, and message syntax in that order.
The evidence confirms successful tag import and communication, but it does not confirm a completed PLC-connected Multi-Watch test. Treat millisecond display and event association as unverified until the online test demonstrates both.
FAQ
Can the cMT3108XP Event Display record alarms in milliseconds?
No. The HMI does not natively record alarms down to the millisecond; capture the timestamp in a capable PLC and transfer it to the HMI.
How do I show a PLC millisecond timestamp in EasyBuilder Pro?
Map the PLC timestamp to a Multi-Watch address, save that watched value through the Event Alarm Log, and use the correct message syntax to display it.
What should I check when the alarm timestamp is missing?
Confirm that the PLC created the millisecond value, verify that the watch address maps to the correct PLC address, and then check the alarm-message display syntax.