ICP DAS USA ISN-101, Руководство пользователя

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iSN-101/104 User Manual
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Host Watchdog
Host Watchdog is used to monitor the RS-485 communication status; if the host
(PC) does not send command “~**” in the time period of WDT Timeout setting, the
enabled Host Watchdog will announce the timeout error and turn the relay output
to Safe value to avoid an unsafe act. Users can not control the relay until the
command “~AA1” is sent to clear the WDT timeout status.
On this tab:
1. Set the time period for WDT timeout, check the checkbox next to Enable WDT
and click the Set WDT button to enable the Host watchdog.
2. Check the checkbox next to Send Host OK to send the “~**” command.
3. Uncheck the checkbox next to Send Host OK to stop sending ~** command, the
Host watchdog timeout will occur and relay will turn to Safe value.
4. Click the Reset WDT button to clear the Host watchdog timeout status.
5. Uncheck the checkbox next to Enable WDT and click the Set WDT button to
disable the Host watchdog.
Note
The relay will not turn to Safe value when alarm for detected liquid is enabled. If
the alarm is enabled, the relay will be linked to the Alarm status. In case an Alarm
occurs, the relay turns ON, it can be used to turn on the user’s alarm light or
beeping alarm or other device.