remote connection via analog phone line

[ltfordnr]

Multi-Tech MultiMobile USB MT9234MU-CDC-XR - Fax / modem - USB - 56 Kbps - V.92

 

[JaxGTO]

One of the Filler companies I work with use a Allen-Bradley switch with a built in analog phone link. Sorry don't have the part number.

 

[CapinWinky]

I've had some luck with a 6net modem that communicates via serial to the PLC in 3rd world countries. We dialed out with an analog line direct to the machine and could get connection. HOWEVER, the connection would drop regularly, so we eventually hooked the modem to a laptop and did TeamViewer so if the connection dropped it wouldn't screw up a project download.

Now, we would just use an e WON with a 3G modem in it. If you have a lot of locations, a family data plan is probably cheaper than a bunch of land lines dedicated to machines, just pop in the SIM cards and you're good to go.

 

[Firejo]

The problem with using a dial up (or leased line) “phone” modem is they require analog phone lines which are on their way out. My number one support call for the modems I support (that operate on Telco lines) is the phone line was changed from analog to digital (many times without customer notification). It’s not a matter of if but when. It will happen the question is how long before it does. The phone company can get many more connections on a single pair of copper in the digital world than the analog one and the more connections they get means the more money it generates. There are “digital phone line modems” (DSL for example) but if you’re going to go digital you might as well make the jump to the internet, which in most cases, is easier to get to most locations than a digital phone line and costs less.
I like the Spectrum option. It looks like it was designed to do exactly what you’re trying to do.