Insulation alarm relay acknowledgement (Ack Al. Relay)
You can set the insulation alarm relay acknowledgment as per the usage of loads connected to the relay.
When the relays are connected to loads (for example, horns or lamps), it is advised to turn off these external signaling devices before the insulation level rises back to a level above the setup thresholds. This can be done by pressing the acknowledge button while in insulation alarm state.
In certain system configurations, it is required to prevent this type acknowledgement and only retrigger the relays when the insulation level rises above the setup thresholds. This is done by changing the corresponding parameter.
The allowed values for this parameter are ON and OFF. The default value is ON.
To set the acknowledge alarm relay ON, select .
To set the acknowledge alarm relay OFF, select .
The device monitors the ungrounded power system insulation in accordance with the following timing diagram:
Acknowledge alarm relay ON
| 0 | An insulation decrease is detected on the system. The insulation resistance drops below the preventive insulation alarm threshold. The preventive insulation alarm relay switches and the preventive insulation alarm indicator light lights up. |
| 1 | An insulation fault is detected on the system. |
| 2 | Once T (insulation alarm delay) has elapsed, the device switches to the insulation alarm state. The insulation alarm relay switches and the insulation alarm indicator LED turns ON. |
| 3 | Press the  button to acknowledge the
insulation alarm. Both the insulation alarm relay and the preventive
insulation alarm relay revert back to their initial state. |
| 4 | The insulation fault is corrected. The alarm LED turns off. The device reverts to normal status. |
Acknowledge alarm relay OFF
| 0 | An insulation decrease is detected on the system. The insulation resistance drops below the preventive insulation alarm threshold. The preventive insulation alarm relay switches and the preventive insulation alarm indicator light lights up. |
| 1 | An insulation fault is detected on the system. |
| 2 | Once T (insulation alarm delay) has elapsed, the device switches to the insulation alarm state. The insulation alarm relay switches and the insulation alarm indicator LED turns ON. |
| 3 | Press the button to acknowledge the
insulation alarm. Both the insulation alarm relay and the preventive
insulation alarm relay does not revert back to their initial state. |
| 4 | The insulation fault is corrected. The alarm LED turns off. The device reverts to normal status. |