The Hardware:
When I plug the UPS into RB’s USB, I can see it in /system resource usb.
Moreover, when I play with plugging-unplugging the UPS, it appears and disappears in /system resource usb of WebFig in real time, so the USB has enough power to work with UPS.
But I can’t make RB to work with UPS. When adding a new UPS entry I can see only “serial0” port.
You need SmartUPS for this.
From RouterOS manual:
“The UPS monitor feature works with APC UPS units that support “smart” signalling over serial RS232 or USB connection”
From APC BackUPS CS 500 technical specification:
“Simple Signalling RS232 cable, USB”
Thank you for reply.
Are you sure?
My UPS does support some kind of smart signalling, but a reduced set of commands. For example it cannot cut the power off at the command from computer.
Actually APC BackUPS CS 500 supports one kind of USB cable and two kinds of RS232 cables: simple and smart, and all three work with computer. When I experimented, I made a smart one, and communicated with UPS in a terminal program very well. I ended my experiments when discovered that RS232 smart cable does not give any advantages over USB cable. So, it can communicate, can report it’s battery drain precisely, everything depends on software (may be some ID string reported by UPS by which all non SmartUPS devices are rejected).
Install USB-hub (even passive) between router and UPS, then reboot router. Sounds like crazy, but it work.
However, in my case, UPS does not show in /system resource usb until plug USB-hub.
I guess that legacy series Back-UPS CS support only USB 1.x at lowest speed 1,5M. But RouterBoard not support it.
PS Better late than never 