SNMP Monitoring of a Transfer Switch relay

Seth Mattinen sethm at
Fri May 14 18:51:25 UTC 2010

On 5/14/2010 10:59, Tom Beecher wrote:
> I'm presently doing some research into a SNMP-enabled device to monitor
> a set of aux contacts on our transfer switch in order to be able to
> monitor it's status (on generator or on commercial) from our monitoring
> platform. I've seen a few interesting devices out there that can
> accomplish this, however I thought I'd query the list to see if anyone
> has thoughts about a particular unit they've worked with.

I went a different way with my electrical gear and used modbus. For me,
the benefits are multiple devices on the 485 bus, monitoring lots of
parameters and I can execute remote commands. I paid something like $300
for the xfer switch modbus card, which was cheaper than any SNMP contact
closure device I could find at the time. I talk to it using Perl
Modbus::Client with my monitoring server as the modbus master. It ended
up being less of a hassle and much more flexible in the long run.

You may or may not have your mind set on dry contact monitoring, but
it's something to think about.


More information about the NANOG mailing list