IP SNMP Temperature Probe

We’ve been looking for IP-based temperature sensors for some time. Our existing temperature solutions are either of two types: 1) environment monitoring systems or their equivalents from APC, or 2) massive building management systems that among many other things also include temperature probes. The latter is far too clunky, and while the former is a lot smaller and simpler, what we really want to have is something a whole lot simpler. Just a temperature probe. Plus humidity perhaps.

A basic criteria, for us, is that the device must be IP-enabled and support SNMP. It also has to be cheap, of course, otherwise we might as will continue with our existing not-so-elegant solutions. The idea is that we want to be able to monitor ambient temperatures throughout our buildings. We, being IT people, would very much prefer an IT type of solution. We believe IT solutions would probably be cheaper and more scaleable than those built on building management systems.

There’s a big gap between the IT world and the BMS world. After some effort searching the Internet, we identify some candidate devices. But they are mostly not available locally, their manufacturers are not represented locally, and sometimes, even if we do manage to contact a supplier or distributor, they aren’t even eager to sell it.

We did manage to get a HWg-STE device pictured above. It works as described, except that we have a little problem with DHCP. It’s supposed to be able to obtain its TCP/IP settings via DHCP, but we were unable to get that to work. But nevertheless, it provided us temperature data via SNMP. We’re still unsure about its cost though, so we haven’t been able to determine if this is an economically viable solution.

More interesting, we’re also trying to find a device that acts as a gateway between IT world of SNMP and the BMS world of Modbus. What we want is a device that will poll field devices via Modbus for data values, and make these values available via SNMP MIB so that we (being IT people) can read using our favourite SNMP manager software. If we can SNMPSET values to the MIB and have that translated into a write operation into the Modbus field devices, that would be even better.

Let me know if you know any suitable products (IP SNMP temperature probes and/or SNMP-Modbus gateway).