The Falcon & Eagle make it easy to keep track of important events when certain values exceed an expected range. This is made possible with the Analog Threshold feature.
Core components of an Analog Threshold:
There are 2 components which must be configured for an Analog Threshold to operate. These are:
- Analog Input: The analog input which the threshold will be evaluated against.
- Enable Low/High Threshold: The bounds of the threshold which would trigger an alarm.
Settings of an Analog Threshold:
- Analog Input: Select the analog input value which will be evaluated with a threshold. When the value of the chosen analog input exceeds the specified range, an alarm is raised which can be handled in a configurable manner.
- Enable Low Threshold: Set the lower boundary of the threshold range. If disabled, the lower boundary becomes infinitely low which will not be exceeded. If both thresholds are disabled, the threshold will never be exceeded.
- Enable High Threshold: Set the upper boundary of the threshold range. If disabled, the upper boundary becomes infinitely high which will not be exceeded. If both thresholds are disabled, the threshold will never be exceeded.
- High Threshold Value: Set the value of the upper threshold boundary.
- Low Value Threshold: Set the value of the lower threshold boundary.
- Upload On Event: Upload on triggered alarm due to the value exceeding the threshold range for the first time. The alarm will remain active until the value returns to the desired threshold range. A record is automatically logged when the alarm is activated.
- Log Record On Event End: Log a record on end of alarm due to the value returning to the threshold range for the first time.
- Upload On Event End: Update a record on end of alarm due to the value returning to the threshold range for the first time.
- Log Record Every Event: Log a record every time the value is checked, regardless of alarm state.
- Upload Every Event: Upload a record every time the value is checked, regardless of alarm state.
- Hysteresis: The value below the upper / above the lower boundary which the analog input value must return to before turning off the alarm. This prevents constant alarm triggering when the analog value is hovering around a threshold boundary value.
- Digital Alarm Input: Select a digital input which will store the current value of the alarm.
Create an Analog Threshold:
To create a new Analog Threshold, add one of the ‘Analog Threshold’ parameters to the system parameters. Disable (or change) the heartbeat period if it is not required.
Analog Threshold example:
Say you wanted to monitor the temperature range of a temperature sensor mapped to analog input 10, ensuring it stays within a 20 - 30 degree Celsius range with uploads whenever the alarm state changes. You would set the Analog Input to "Input 10", set Enable Low Threshold and Enable High Threshold to "Yes", set the High Threshold Value to "3000" and the Low Threshold Value to "2000". You would also set Upload On Event to "Yes" and Upload On Event End to "Yes". Finally, you could set Hysteresis to "500" (5%) to prevent constant alarm triggering.
These settings can be changed in the system parameters on the OEM server. The default settings are shown below: