RS232 Communications Protocol & Command Set
Communications Protocol
Baud rate:_______2400 bps | Stop bit:_______________1 bit |
Start bit: ____________1 bit | Parity:________________None |
Data length:_________8 bits | Flow control:____________one |
|
|
Controller Commands
Commands and responses are in the form of ASCII character strings terminated with a carriage return <CR> ASCII character 13 (hex).
It is important to understand how the UPS circuitry switches power to the outlets in order to use the outlet switching commands effectively. The following diagram provides a basic illustration:
DB9 Pinout Diagram | ||||
5 | 4 | 3 | 2 | 1 |
6 |
| 7 | 8 | 9 |
PIN NO. |
| SIGNAL |
| |
1 |
|
| - |
|
2 |
| TRANSMIT | ||
3 |
| RECEIVE |
| |
4 |
| DTR |
|
|
5 |
| SIGNAL GROUND | ||
6 |
|
| - |
|
7 |
| RTS |
|
|
8 |
|
| - |
|
9 |
|
| - |
|
DTR - Data Terminal Ready | ||||
RTS - Request To Send | ||||
AC INPUT/BATTERY | To |
MAINNCL
Figure 2.1 UPS Power Switching
To Critical Load (CL) Outlets
The UPS provides one bank of switched outlets (Outlet Bank 1) that can be controlled independently. These are referred to as
The other outlet bank (Outlet Bank 2) will be referred to as Critical Load (CL) Outlets.
Note that NCL outlets cannot be energized unless the critical load outlets are on.
NCL outlets are designated for equipment that is considered
Power will be turned off if the battery charge falls below a set threshold (refer 2.5).
It is desirable to have the ability to switch the power to the outlets on and off to force a “hard” reboot of equipment. Devices such as satellite receivers often “crash” and must be reset.
The following are commands made by the controller to the UPS:
Main Power On
Send to UPS: | MAIN_ON<CR> |
If power is not switched off due to low battery conditions:
Action:AC power is switched ON to the CL out lets by closing the AC input relay or turn ing on the inverter.
Response from UPS: | CL_OUTLETS_ON<CR> |
| NCL_OUTLETS_ON<CR> (if NCL relay is |
| closed) |
If power is already switched off due to low battery conditions:
Action:None
Main Power Off |
|
|
| MAIN_OFF<CR> | |
Send to UPS: | ||
Action: | All outlets are | |
|
| necting the AC input relay and turning |
|
| off the Inverter. |
Response from UPS: | NCL_OUTLETS_OFF<CR> | |
|
| CL_OUTLETS_OFF<CR> |
Response from UPS: | LOWBATT<CR> |
USA & Canada (800) |
| 13 |
