2.2.6Communications
The UPS has a DB-9 (9 pin female) connector on the rear to allow UPS status communications with a computer system running MultiLink™ software. The DB-9 is capable of supplying serial communication, on battery and low battery signals. MultiLink, Liebert’s UPS monitoring and shutdown software, is shipped with the UPS, along with a 10-ft. (3m) DB-9 cable required for running MultiLink.
The UPS can signal “on battery” and “low battery” using opto-couplers. When the UPS is operating in Battery mode, it can receive a signal from the host computer system that will shut down the UPS (after gracefully shutting down the operating system on the host computer system) when the remaining battery run time is low. The timing of the signal depends on MultiLink’s configuration settings. This shutdown signal (5-12VDC) must have a duration of at least 1.5 seconds for the UPS to be shut down. The UPS communicates via serial communications using Liebert ESP II protocol.
The PowerSure PSA has a USB interface port for communication that will work with the built-in Microsoft Power Manager software on the user’s PC, if the PC is so equipped. It will provide UPS status and manages the automatic orderly shutdown of the computer. The UPS (USB) communications meets HID standard, version 1.11. All USB models are compatible with Microsoft Windows 2000, Windows XP and Mac OS 10.2 or later. All USB models ship with a 6- ft. (1.8m) USB cable.
The pin out configuration of the DB9 connector is:
Pin | Assignment Description |
1 | Low Battery (open collector) |
2 | UPS TxD (typical RS-232 levels) |
3 | UPS RxD (typical RS-232 levels) |
4 | Battery Mode Shutdown (5-12V) |
5 | Common |
6 | Any Mode Shutdown (short to pin 5) |
7 | Low Battery (open emitter) |
8 | AC Fail (open emitter) |
9 | AC Fail (open collector) |
Maximum voltage and current on Pins 1, 7, 8, and 9 is 55VDC; 10.0 mA.
PowerSure PSA | 8 | Guide Specification |
350 – 1000VA | | SL-23271 8/03 |