I was looking for a portable 120V charger to replace my cheap Vector which has a fan that usually doesn't work, and when it does sounds like a Mack truck. So I bought a $113 Schumacher Speed Charger that bills itself as deep-cycle capable. I hooked it up to a couple of deep-cycles I knew had been seriously disharged. In 15 minutes it told me they were 100% charged. I hooked my Vector up to the same batteries and found they were not fully charged, but still serious discharged.

I figured there was something wrong with the Schumacher so I took it back and got another. Again, it told me the batteries were charged 100% in about 15 minutes. So I took that one back and got my money back.

My Vector is old and rumbly, but it puts a full charge on my batteries. I was pretty disappointed in the Schumacher. Not sure why this charger wouldn't charge my deep cycles. The manual and box clearly states it will.

If you buy an electronic Schumacher, be cautious whether or not your batteries really are fully charged.

Had a cheap $50 one for years with no issues...................batteries always charged!

Had a cheap $50 one for years with no issues...................batteries always charged!

me too i still use it, has 2 amp-10amp- automatic and manual switches on it, i don't think it is a speed charger though.so thanks for the warning.

Don't know which model you have.  I spent half that much on my Schumacher electronic and have been pretty pleased.  Off course, I've still got my old 10a model that's around 15+ years old that I also use. 

I'm not knocking Schumacher.  Tehy make good products.  Just the Speed Charger doesn't appear to handle Deep-Cycles well, despite what's written on the box and manual. 

I may be wrong, but I don't think Deep-Cycle batteries were meant to be Speed Charged. :-/

The Speed Charger I had allowed a setting for deep cycle or conventional batteries. I had the 2-6-10-manual. Speed Charger is just a name and are made in different capacities and charge rates.

It worked very well for several years and I gave it to the person that bought one of my boats.

The one I have is very particular as to placement of the alligator clips.  If they're not just right on the posts, the charger will give a false reading.

I have the $50 one as well. Still use it. It has never let me down.

My schumacher charger sometimes does the 100% charge thing in 20 minutes or so but I think its a battery issue and not the charger. Mine only does this during the cooler winter months and when the battery has been sitting for awhile....battery going on its forth year. I'll often charge at 2amp when cold and it seems to help with the issue.

Serioulsy discharged batteries can be damaged from being seriously discharged, they drop the charge in an eyeblink so it may not be the charger but the battery. I killed a couple of batteries for not charging them full after use and leaving them there for months without charging, then I plugged them to the charger, charged them for use a couple of days later and to my surprise they were discharged, took them to the place I bought them and that what the first thing they asked me, if I charged them before storage, said no, the technician took a look at them and gave me a bonus ticket for 20 dollars discount per battery in the purchase of a new one.