Battery Tender recommendation
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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C-Tek 3300. They are excellent battery maintainers 
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
I have read that other people are not happy with the Wal-mart Schumacher tenders but I have 4 of them and have not had an issue with any of them yet, 5 years running.
another option is the solar chargers;
I use them where ever power is not readily available and they keep batteries topped off as well.
another option is the solar chargers;
I use them where ever power is not readily available and they keep batteries topped off as well.
Burning Brakes
Joined: Sep 2009
Posts: 1,124
Likes: 140
From: Western New York
I, too, have the Walmart battery tenders @ $19.95 each. I have 7 of them that I've used for at least 9 years and have never had any problems with them. They're all hooked up to batteries on the work bench for the Corvette, boat, tractors, lawn mower, and trolling motors. If I didn't have them, it would cost me an arm and a leg to replace everything.
Duane
Duane
Drifting
Joined: Aug 2013
Posts: 1,453
Likes: 88
From: Easton Pennsylvania
This is the one I use on my vehicles. It mounts with a supplied l-bracket right up against the battery and all you do is just plug it into an extension cord. Cant be any easier. And they run under 30 bucks on Amazon.
Schumacher SE-1-12S0CA
Schumacher SE-1-12S0CA
Last edited by persuader; Feb 4, 2015 at 08:08 PM.
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Drifting
Joined: Mar 2011
Posts: 1,347
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From: Kernersville NC
I have used the BatteryMinder model 12117 (newer model 1500) for several years with good results. I leave one on each Vette when they are sitting for a while. I put one of them on my generator for a few days about once a month. The 12117 is at Northern Tool for $29 if you can find them in stock. The newer 1500 is $49.
edit: 12117 is available online
edit: 12117 is available online
Last edited by flyeri; Feb 4, 2015 at 09:02 PM.
Drifting
Joined: Oct 2009
Posts: 1,725
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From: marietta, GA
I had a bad experience with my C-tek. Had one on my 2003 Corvette, the other on the Harley. We had a storm and the power must have gone off. When I got home the lights on the chargers were off and the circuit breaker was ok. Both chargers were cooked but the Corvette's EBCM was fried. Cost me almost $600 to replace. C-Tek replaced the chargers but would not pay for the damage to the Corvette. I never used the replacement chargers they sent. Through them out.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
I believe C-Teks intention was that their charger would not overcharge your battery. There is no way it would protect your circuits from a high voltage spike caused by lightning unless they added a MOV (metal oxide varistor) to it. A standard circuit breaker won't protect the circuit either, its a current sensing device not voltage hence why it hadn't tripped. If you are in a high lightning affected area I would suggest fitting a surge protection device to your supply, these divert voltage spikes to earth.
Racer
Joined: Nov 2003
Posts: 430
Likes: 60
From: Central KY
With the exception of gasoline, auto batteries are probably one of the most dangerous items on our cars. I too have used "tenders" and have had success with batteries maintaining their charge. But what happens when an extraordinary condition occurs, i.e. a huge electrical spike or a prolonged brownout. Are the "cheap" tenders designed and manufactured to handle these conditions and protect the batteries in our cars? Or for that matter are the expensive models?
Perhaps a electrical engineer can chime in with some advice.
FYI, the last Schumacher battery chargers I purchased never worked as it should and ruined at least one battery.
Perhaps a electrical engineer can chime in with some advice.
FYI, the last Schumacher battery chargers I purchased never worked as it should and ruined at least one battery.
Le Mans Master
Joined: Nov 2016
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From: Lake Tahoe, CA
Le Mans Master
Joined: May 2003
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From: Fernandina Beach FL
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The problem is- taking AC from your house- converting to DC to charge the battery.
If the power surges to the battery tender from lightning/brown outs-it can torch the internal rectifier(s) or go through to the car's electrical.
When that happens- the battery tender is sending AC or high voltage DC to your car's electronics and battery. The battery can handle some - but not the electronics.
IF you are gong to run a tender- I would think a SURGE PROTECTOR should be a requirement.
If the power surges to the battery tender from lightning/brown outs-it can torch the internal rectifier(s) or go through to the car's electrical.
When that happens- the battery tender is sending AC or high voltage DC to your car's electronics and battery. The battery can handle some - but not the electronics.
IF you are gong to run a tender- I would think a SURGE PROTECTOR should be a requirement.
Melting Slicks
Joined: Jul 2004
Posts: 3,248
Likes: 48
From: westland mi
Been using the Battery Tender Jr's for 15 yrs and never a problem till the Transformer blew, had
the Vette and Bike and DD hooked up at the time, all 3 Battery Tenders fried but no damage to any of the Vehicles.
the Vette and Bike and DD hooked up at the time, all 3 Battery Tenders fried but no damage to any of the Vehicles.
