MILPOWER SOURCE
110BA1UM, REV(B)
15
8.2
RS-232 Communication Interface
The RS232 serial communication interface is available through connector J4 ( a DB9 female
connector located on the rear panel of the UPS.) This interface allows control and monitoring of the
UPS by a host computer through the serial RS232 communication link. For further information
about this feature refer the M120BA-1 Software User Manual. Table 3 shows the standard RS232
pin assignment.
Table 3 - RS232 Connector J4 Pin Assignment
Pin
I/O
Symbol
Description
1
Internally shorted to J3 pin 5. (not used by RS232 link)
2
Input
RXD
Receive Data
3
Output
TXD
Transmit Data
4
Output
DTR
Data Terminal Ready
5
---------
SG
Signal Ground
6
Input
DSR
Data Set Ready
7
Output
RTS
Request To Send
8
Input
CTS
Clear To Send
9
Internally shorted to J3 pin 9. (not used by RS232 link)
8.3
Remote ON/OFF Interface J5
Important note: The M110BA-1 is shipped with a matting connector plugged into J5, with a jumper
that enables the unit. If remote ON/Off is not desired, do not remove it.
The
remote ON/OFF Interface J5 provides a mean for turning the UPS ON and OFF by a remote
panel switch. When pin 8 or 15 of J5 are connected to pin 7 or 14 of J5 (8 is internally connected to
15 and 7 is internally connected to 14) the UPS is enabled. It will be ON only if the Master ON/OFF is
also ON. When pins 8 and 15 are not connected (externally) to pins 7 or 14 the UPS will be OFF
regardless of the position of the switches on the front panel.
To control the UPS by the remote switch, leave the front panel switches in the ON position and turn
the UPS ON and OFF by closing (ON) and opening (OFF) the remote switch.
The remote switch should be rated to 28Vac, 0.5AMP.
Pin
Symbol
8,15
Remote ON/OFF
7,14
Remote ON/OFF RTN
1
÷
6
9
÷
13
Not used
