The Tripp Lite SmartPro cable (part number 73-0743) is a proprietary intelligent serial cable used to connect a Tripp Lite SmartPro UPS to a PC running PowerAlert monitoring software. The cable carries bidirectional serial data on Tx, Rx, and GND lines using a non-standard pin mapping on the UPS-side DB-9 male connector. It was designed for the SMART port (LAN 4.1) fitted to late-1990s SmartPro rack and tower UPS units. The PC end presents a DB-9 female connector with several pins shorted together to satisfy the PC serial port’s handshake requirements.
9 pin D-SUB male connector to the UPS
9 pin D-SUB female connector to the computer
| UPS Signal Name | DB-9 Male (UPS end) | DB-9 Female (PC end) | PC Signal Name |
|---|---|---|---|
| Tx | 7 | 2 | RxD |
| Rx | 9 | 3 | TxD |
| Common | 8 | 5 | GND |
Notes
- Pins 7 and 8; pins 1 and 4 and 6 shorted at the PC end connector.
- The UPS uses non-standard pin assignments: Tx on pin 7, GND on pin 8, and Rx on pin 9, rather than the RS-232 standard positions.
- Shorting pins 1, 4, and 6 at the PC end satisfies the DCD, DTR, and DSR handshake lines expected by the PC serial port.
- Standard straight-through and null-modem cables are not compatible; only the proprietary 73-0743 cable or an equivalent wired to this specification will function correctly.