BE650MC and Motorola Netopia 2210-02 ADSL Modem - unhappy combination...

[Anonymous user]

I have the following items attached to my APC BE650MC Back-UPS

Motorola Netopia 2210-02 ADSL Modem
MagicJack Plus
D-Link WBR-2310 Router
D-Link DSS-16+ Switch

That's it. All items are plugged into the battery backup ports. I doubt there are very many volts in the combined total of the items plugged into the UPS. The d-link switch will likely be set to the surge-only plug outlets later.

All the above items work flawlessly on the backup unit except the modem. Even with power on, the modem does not function correctly. If I plug the modem into the wall socket instead, everything else plugged into the UPS works fine. The idea behind buying the UPS was so that while I'm on the phone and we get a quick brown out or one of the inevitable two-second power outages that happen every Sunday, I won't be disconnected on the MagicJack phone. That means the modem needs to work nicely with the UPS. When tested with my multimeter, each plug outlet on the UPS shows ~120 Volts. (119 to 123). When unplugged, the voltage drops down to 80v with everything except the modem plugged in. According to UPS phone support, this is within normal parameters for this UPS unit.

The modem looks like it's functioning properly when you look at the blinking lights while it's connected to the APC. However, the homepage for the modem and the entire web are not available. The router home page and local ethernet/print services are available. Again, when I plug the modem directly into the wall instead, everything else functions normally. Only when I plug it into any socket on the UPS does my web connection go away.

I would be grateful for any insights as to why my modem doesn't function correctly when plugged into this unit and what can be done to rectify the situation. This is true whether or not the DSL phone line is connected through the UPS's RJ11 ports.

Is the problem more likely specific to the 2210 modem or 650 UPS?

Further, I've been thinking about going back to Cable internet, using a Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem. I'm curious if this modem will function reasonably well with this UPS.

[BillP]

Generally speaking, the UPS doesn't care what is plugged into it as far whether it will provide power or not. Of course if the device caused it to overload, that's a different story. Based on what you've noted here, that is not the case. I've heard of issues with modems not working(sending data through the phone lines)with the phone lines going through the UPS but I've not heard of issues with the UPS POWERING the modem. The UPS is either outputting power or it's not. Have you tried the modem in multiple outlets?

[Anonymous user]

I've tested each outlet on the unit for power. They are all similar.
I've tested several outlets with the modem, both the battery and surge-only side.

The only thing I can guess is that there is flaky interference transmitting through the UPS that is conflicting with the working of the modem. In other words it's a bum UPS.

I'm going to swap it at the store where I bought it, try out the new one and see if that will make a difference.

Is the UPS supposed to hum like that?

[Anonymous user · Accepted solution]

I brought the unit back and got a replacement. That one works perfectly.

For future reference, a flaky UPS can impact the functionality of a modem that is powered by it, probably due to frequency interference with the modem.

I'm posting with the replacement UPS on-line now.

Thanks, Chrisri30