Level Alarm
medium
Produce Hi and Lo alarm outputs around setpoints with a deadband to avoid chatter.
What it teaches
Two independent latched comparators with deadband — Hi alarm sets at HiSP, clears at HiSP - deadband; Lo alarm sets at LoSP, clears at LoSP + deadband. Teaches multi-threshold alarming and process-control deadband.
Inputs and outputs
| Tag | Type | Default | Description |
|---|---|---|---|
| In_Level | REAL | 50 | Process variable level |
| Cfg_HiSP | REAL | 80 | High alarm setpoint |
| Cfg_LoSP | REAL | 20 | Low alarm setpoint |
| Cfg_Deadband | REAL | 5 | Deadband applied to clearing alarms |
| Sts_HiAlarm | BOOL | — | High alarm flag |
| Sts_LoAlarm | BOOL | — | Low alarm flag |
Required behavior
- Sts_HiAlarm sets to 1 when In_Level is greater than or equal to Cfg_HiSP.
- Sts_HiAlarm clears to 0 when In_Level is less than Cfg_HiSP minus Cfg_Deadband.
- Sts_LoAlarm sets to 1 when In_Level is less than or equal to Cfg_LoSP.
- Sts_LoAlarm clears to 0 when In_Level is greater than Cfg_LoSP plus Cfg_Deadband.