Communications Alarms Occur Repeatedly
- Verify that cable connections are correct and secure.
- If basic serial communications seem to be occurring on the industrial network, then the problem may be too low a setting for the communications alarm trip delay.
- The amount of time communications with a specific channel may lapse is dependent on many factors. One of the main factors is how many channels are active. An RTU scanning 256 channels may require a communication alarm trip delay of 200 seconds or more to avoid nuisance alarms.
- One practical approach to determining a suitable initial setting for the communications alarm trip delay is to query the RTU for the channel scan time with Keycode 9 0 2 N 1, where N is the Net number (usually 1). It is suggested that you configure twice that value for the communication alarm failure trip delay, which can be accessed using the Protocol Port tab under Configuration | Devices in Alarmware™.
See Also
Channel Operations Testing
Failed Network Communications
Net 1 (Industrial Networks) Settings
Scan Time and Channel Latency