I’ve taken the plunge and gotten a TS-7670 ordered in a DIN-rail mount for monitoring the battery. Not sure what the shipping will be from Arizona to here, but I somehow doubt I’m up for more than AU$300 for this thing. The unit itself will cost AU$250.
Some will argue that a Raspberry Pi or BeagleBone would be cheaper, and that would be correct, however by the time you’ve added a DIN-rail mount case, an RS-485 control board and a 12V to 5V step-down power converter, you’d be around that figure anyway. Plus, the Raspberry Pi doesn’t give you schematics. The BeagleBone does, but is also a more sophisticated beast.
The plan is I’ll spin a version of Gentoo Linux on it… possibly using the musl C library to keep memory usage down as I’ve gone the base model with 128MB RAM. I’ll re-spin the kernel and U-Boot patches I have for the latest release.
There will be two functions looked after:
- Access to the IPMI/L2 management network
- Polling of the two DC power meters (still to be fully designed) via Modbus
It can report to a VM running on one of the hosts. I believe collectd has the necessary bits and pieces to do this. Failing that, I’ve written code before that polls Modbus… I write such code for a day job.