|1||RS232 Receive Data||Receives incoming RS232 communication data.|
|2||RS232 Transmit Data||Sends outgoing RS232 communication data.|
|3||Normally Open On-Battery Contact||A normally open contact that closes 15 seconds (pulls to Common) after the UPS switches to battery power.|
|4||Signal Ground (Common)||The signal ground for all signal pins.|
|5||Normally Open Low-Battery-Alarm Contact||A normally open contact that closes (pulls to Common) during a Low Battery Alarm.|
|6||Plug and Play Sense for Windows 95||--|
|7||Remote Shutdown||Connecting this pin to Common for at least 5 seconds, while the UPS is operating on battery, shuts the UPS off after 120 seconds.|
|8||Normally Closed On-Battery Contact||A normally closed contact that opens (releases from Common) after the UPS switches to battery power.|
Contacts consist of open collector circuits capable of switching up to +30 VDC, 6 mA resistive load.
Note1: for connection of this UPSes to the computer, using the proprietary closed software Best Power CheckUPS II Suite, is necessary the cable INT-0001 for smart signalling (CheckUPS II Advanced), or the cable INT-0051 for voltage signalling (CheckUPS II Basic).
Note2: for additional information how to connect this UPSes to the computer, using the open source software, please look APCUPSD Voltage Signalling Simple-Custom Cable for Best Power Fortress Rackmount 750 VA, 1050 VA, 1425 VA, 1800 VA, and 2250 VA.