Battery Tender Mortality - Am I Killing Them, Somehow?

[kudzu]

I have been a big fan of Battery Tenders for years. Suddenly, I've got at least three that seem to have died. Anybody else have a high Battery Tender mortaility rate? Could I be killing them somehow?

[SC_Jack]

Have you had any lightning/thunder storms? I lost one last summer when lightning ran into the garage while mine were plugged in. I had three going but it only got one of them. Apparently, it ran from the ground, through the concrete and directly to the one that got fried. I didn't realize what had happened until I noticed that it wasn't working and I smelled a faint smell of burned electronics.

Since then, I unplug all of them when we're going to have storms.

[kudzu]

Have you had any lightning/thunder storms?

Good question! While I can't confidently rule out that possibility, I don't think so. However, the rural area in which I live is served by an electric co-op notorious for brown outs, hiccups and surges. But, I haven't had problems with other electrical appliances.

[johnt650]

I had one fried by lightning as well and didn't catch it until I found my battery cooked dry. The unit went to the charge mode after the strike.

[KMG_365]

Are they "frying" or just ceasing to work? Reason is the little screws that hold the wires to the terminals under the cap of the BMW-plug end are notorious for working their way loose as the wire expands and contracts from the initial tension originally applied when they were first assembled. Unscrew the cap end and tighten the screw and see if that fixes it.

 

That's the best case scenario. Otherwise, you might try putting a surge protector in-line between the BT and the house wiring to eliminate the possible damage coming from that end, and you might set the unit on a piece of thick cardboard or foam if its on a bare concrete floor in case you've got some sort of leak there.

 

Good Luck!

[Rinkydink]

I've had the same one for years with no problem. Knowing you can't always get home in time to unplug b4 those afternoon storms pop up, you might try a surge suppressor.

[SageRider]

Forgive me if I am asking a stupid question, but have you confirmed that AC input power is present when plugging in the chargers?

[johnt650]

Fried was the wrong terminology for mine. My next door neighbors house took a direct hit and I had a very close strike which caused me to lose my ethernet board, the next day I noticed that the steady red light was on the battery tender. I took the bike for a short ride, and after a stop it would not restart, when I added water to the battery it fired right up. Apparently the tender went from the steady green maintenance light to the charge position and stayed there. I drew the assumption that it was also a victim of the lightning as my neighbor had significant damage. Perhaps this was just coincidence but I'm using a surge protector for the future just in case.

[tallman]

What Jamie said.

It's happened probably 10 x over last 2 years.

[SC_Jack]

FWIW: I had mine mounted on a wooden board and hooked to a surge suppressor but the lightning went directly to the charger & fried it but it didn't do any damage to the bike, the surge suppressor or the other charger that was connected to the same surge suppresor. Just a straight, direct hit to the battery charger. Unplug your charger when there's lightning in the area.

[kudzu]

Forgive me if I am asking a stupid question, but have you confirmed that AC input power is present when plugging in the chargers?

Yes.

[KMG_365]

Forgive me if I am asking a stupid question, but have you confirmed that AC input power is present when plugging in the chargers?

Yes.

So I assume then that you've also checked the terminal screws and they are not loose? Rats.

 

This next comment probably doesn't apply to you, "kudzu" (since you've replaced the tenders and they've then worked fine), but everyone else reading this should know that the BMW Battery tender also won't charge a completely dead battery. The tender has to sense SOME residual charge on the input to begin charging the battery. If you've totally killed your battery, you might need to "jump" it a bit with something else to give it at least a minimum surface charge before the tender will kick on.

[kudzu]

...BMW Battery tender also won't charge a completely dead battery. The tender has to sense SOME residual charge on the input to begin charging the battery.

Interesting! Since the batteries that I am using Battery Tenders on are relatively new, that's not my problem. But, I didn't know that and it is useful information. Thanks.