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6. SYSTEM SOFTWARE COMMANDS
(via the rear panel RS232 interface)
For sophisticated applications, the Mesta UPS system provides an RS232 communications interface
which can link the microcontroller with a remote computer or terminal. This two-way link allows users to
1) collect detailed information on power usage and other characteristics of the load to which the UPS is
connected and 2) remotely control the UPS or the load. (For example: a software package can be
developed to alert the computer to automatically save data and shut itself down when the UPS battery
power is dwindling and no emergency generator is available.)
Any computer or terminal equipped with an RS232 serial port capable of a 1200 baud rate can be used
to communicate with the UPS. If a terminal is being used, one can begin sending commands to the
UPS as soon as a 3-wire hardware interface is in place. Once communication has been established
with the UPS, the UPS will provide a ">" prompt, which signals the operator to enter a command.
By typing
S <enter>
to obtain the UPS' operating status, the following typical screen appears:
Software Commands:
UPS information may be examined using the following commands:
Sn
Status command displays the present status of a parameter. To display the status of a
particular parameter, type
Sn<enter>.
"
S
" indicates the status command, "
n
" represents a
letter from A to Q designating the parameter you desire to observe, and
<enter>
indicates
an enter key, which is used to terminate the command. Table 4 contains the list of available
parameters that may be examined. As an example, if the present AC line voltage is to be
examined, one would type
SA
followed by striking the
<enter>
key. One can also just enter
S<enter>
with no parameter letter and obtain a status update of 12 of the most useful
parameters all at once.
Vn
View
command is similar to the Status command except the View command will continually
display the status of the selected parameter until one presses the escape key on the
computer or terminal keyboard. To continually view the status of a particular parameter, type
Vn<enter>
. "
V
" indicates the View command,
"n"
represents a letter from A to Q
designating the parameter to be viewed, and
<enter>
indicates a carriage return (or Enter
key) which is used to terminate the command. Again, Table 4 contains the list of available
parameters that may be examined. As an example, if the AC line voltage is to be viewed
continuously, one would type
VA
followed by striking the
<enter>
key. One can also just
enter
V<enter>
with no parameter letter and continually view the status of 12 of the most
useful parameters all at once.
<Esc>
The escape key can be pressed at any time to abort any command. After pressing the
escape key, the UPS will display
<Esc>
to indicate such a key was pressed followed by a
new ">" prompt. At such a time a new command can be entered.
*** MESTA UPS STATUS ***
LINE_VOLT AB/BC/CA= 210.8/210.6/210.9 LINE_AMPS A/B/C = 11.4/ 10.1/ 11.4
LOAD_VOLT AB/BC/CA= 212.8/212.1/211.8 LOAD_AMPS A/B/C = 0.0/ 0.0/ 0.0
FREQ_HZ LINE/LOAD= 60.01/60.04 LOAD_PERCENT A/B/C= 0%/ 0%/ 0%
BATT VOLT/AMPS/CHG= 274.5/ 0.4/100% LOAD_PWR KW/KVA/PF= 0.0/ 0.0/ .00
TEMP HSA/HSB/HSC = 24.8/ 26.3/ 26.7 TEMP ROOM/AMBIENT= 23.1/ 25.4
UPS= * ON AC LINE* NORMAL OPERATION AC_LINE_STATUS= GOOD
