yeah till you get a bad maintainer and it goes nuts and fry's a whole bunch of electrical things, ASK me how I know this LOL
any particular brand?
the one I had issue with was a Schumacher 1.5A 6V/12V Fully Automatic Battery Maintainer
exact model SEM1562A
and a link to them where I bought em!
was less than a yr old too, I contacted the company due to all the damages and was under warranty, at first they were great, even said they would PAY for any damages the tender caused
then they stopped responding to my phone calls, NEVER ever would return one, NOT returning emails, and to date, NOT once got back to me after saying they would work with me ! started a claim number with them, TRIED to send them unit back, and they again have NOT returned any of my calls, messages or emails!, even though they gave me a private number to call, (no call backs on that # ) or leaving any messages on the 800 number and voice mails. and emails to a private email, never get a single reply back either!
SO< IMO< they offered ZERO help and worse, straight up lied , and then they have been hiding from the issue's there product caused me( well over a grand in damage) which is bad enough, but to have a company, just run from a issue after they said they would help, without even a reason WHY there not getting back to me>>
Is some very BAD customer service IMO!
and I threw out the other 2 of there maintainers I had(bought 3 at the same time on sale at TSC) as I have NO faith in them, the second charger I caught charging my snowmobile's battery to 15.5 volts, so, that one also seemed BAD, as according to them should NEVER go past 14 volts!
they even told me to STOP using them! and they would refund me for them!
BUT again, NO response since and no standing behind there words I guess from them!
made a LOT of work for me and tech I had to hire to problem solve all the things that got damaged on my skid steer!
tenders/maintainers are great when they work right, but WOW the damages this one did to me, I could have bought a new battery ever 6 months for many yrs and NOT spent what the maintainer cost me in damages!