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What events can cause a datapoint's status to be AL_UNKNOWN on the i.Lon100?
Question Detail
Sometimes I see AL_UNKNOWN as the status from the Alarm Generator on my i.Lon100. What events can cause a datapoint's status to be AL_UNKNOWN on the i.Lon100?
Solution
The alarm type is set to an higher alarm condition after the set time UCPTalarmSetTime is elapsed. The alarm is set to a lower alarm type when the clear time UCPTalarmClrTime is elapsed.
This functionality is recommended for binary inputs like SNVT_switch or SNVT_lev_disc only.
Example 1 Binary Input:
Definition SNVT_switch:
| SNVT_switch.value | SNVT_switch.state | Binary state |
| 100.0 | 1 | ON |
| 1.0 | 1 | ON |
| 0.0 | 1 | OFF |
| 100.0 | 0 | OFF |
FN_GT selected; CompValue = SNVT_switch; Data Value = SNVT_switch
| Data Value | CompValue | Alarm Output alarm_type | Alarm2 Output alarm_type |
| OFF | ON | AL_NO_CONDITION | AL_NO_CONDITION |
| ON | ON | AL_NO_CONDITION | AL_NO_CONDITION |
| ON | OFF | AL_INVALID | AL_INVALID |
| AL_OFFLINE | ON/OFF | AL_OFFLINE | AL_OFFLINE |
| AL_INVALID | ON/OFF | AL_INVALID | AL_INVALID |
| AL_NUL | ON/OFF | AL_NUL | AL_NUL |
| AL_ERROR | ON/OFF | AL_ERROR | AL_ERROR |
| AL_INVALID | ON/OFF | AL_INVALID | AL_INVALID |
| AL_CONSTANT | ON/OFF | AL_CONSTANT | AL_CONSTANT |
| ON/OFF | AL_OFFLINE | AL_UNKNOWN | AL_UNKNOWN |
| ON/OFF | AL_INVALID | AL_INVALID | AL_INVALID |
| ON/OFF | AL_NUL | AL_UNKNOWN | AL_UNKNOWN |
| ON/OFF | AL_ERROR | AL_UNKNOWN | AL_UNKNOWN |
| ON/OFF | AL_INVALID | AL_UNKNOWN | AL_UNKNOWN |
Example 2 Binary Input:
FN_EQ is selected ; CompValue is not bound; Default value of CompValue is ON; Data Value =SNVT_switch
| Data Value | CompValue | Alarm Output alarm_type | Alarm2 Output alarm_type |
| OFF | ON | AL_NO_CONDITION | AL_NO_CONDITION |
| ON | ON | AL_ALM_CONDITION | AL_ALM_CONDITION |
| AL_OFFLINE | ON | AL_OFFLINE | AL_OFFLINE |
| AL_INVALID | ON | AL_INVALID | AL_INVALID |
| AL_NUL | ON | AL_NUL | AL_NUL |
| AL_ERROR | ON | AL_ERROR | AL_ERROR |
| AL_INVALID | ON | AL_INVALID | AL_INVALID |
| AL_CONSTANT | ON | AL_CONSTANT | AL_CONSTANT |
This solution applies to the following products:
- i.LON 100 e2 (Ver 1.1)
- i.LON 100 e3 (Ver 3.0)
Last Modified:
Solution: KB625
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