Remote UPS Shutdown Signal Buttons Always Available

• Microsoft Windows NT Advanced Server, version 3.1
• Microsoft Windows NT operating system, version 3.1

The uninterruptible power supply (UPS) service in Windows NT has an unexpected behavior in the user interface. If the Remote UPS Shutdown check box is not selected, the signal level option buttons are still available. This article describes how and why this unusual behavior is required.

MORE INFORMATION

The UPS service is started from the Control Panel. It is used to configure desired options and operation of the UPS hardware. You can enable the service by selecting the "Uninterruptible Power Supply is installed on:" check box.

The Remote UPS Shutdown configuration option allows the Windows NT system to tell the UPS to turn off. This is done when Windows NT is gracefully shutting down.

If the Remote UPS Shutdown check box is selected, this indicates that the UPS device supports this functionality; the appropriate signal level must then be selected to indicate how it works.

If the Remote UPS Shutdown check box is clear (not selected), the signal level option buttons are still available. The expected behavior is that if the option is disabled, the option buttons would be unavailable; but this is not the case. If the Remote UPS Shutdown check box is clear and the signal level option buttons are available, there are two possibilities:

• The UPS device does not support this functionality. Therefore, it doesn't matter what the signal level option buttons are set to.

  -or-

• The UPS device does support this functionality, but you do not want to use it.

  In this case, you still need set the signal level option button that the UPS expects so that the UPS does not work incorrectly. Even if you do not want to use this feature, the UPS is still going to interpret the signals on this line. If it receives a certain signal, it will shut itself down.