Additional UPS Features
31
NCR 4072 UPS Site Preparation, Installation, and Operation Manual
S
05147374 Rev C
Uncontrolled Copy
DB-9 Communication Port
To establish communication between the UPS and a computer, connect
your computer to the UPS communication port using the supplied
communication cable.
When the communication cable is installed, power management software
can exchange data with the UPS. The software polls the UPS for detailed
information on the status of the power environment. If a power
emergency occurs, the software initiates the saving of all data and an
orderly shutdown of the equipment.
The cable pins are identified in Figure 20 and the pin functions are
described in Table 2.
3
8
7
9
1
6
2
4 5
UPS Rear Panel
Figure 20. Communication Port
Table 2. Communication Port Pin Assignment
Pin
Number
Signal Name
Function
Direction
from the UPS
1
Low Batt
Low Battery relay contact; 20 mA,
30 Vdc contact rating
Out
2
TxD
Transmit to external device
Out
3
RxD
Receive from external device
In
4
DTR
PnP (Plug and Play) from external
device (tied to Pin 6)
In
5
GND
Signal common (tied to chassis)
—
6
DSR
To external device (tied to Pin 4)
Out
7
—
No Connection
—
8
AC Fail
AC Fail relay contact; 20 mA, 30 Vdc
contact rating
Out
9
Power Source
+V (8 to 24 volts DC power)
Out
