quote:

Originally posted by konata88:
Hey, sorry another dumb question.

Can I use two of the 25' Battery Tender extension leads in-line?

I want to place the Battery Tender in a particular spot near the AC outlet and use it for two cars. I can reach one car with a single 25' extension. But to reach the other car, I need an additional extension. Okay to use a second extension in-line (for long periods - days at a time - just driving to lubricate stuff / avoid tire flat spots / etc).

If there is a spot from which the Tender could reach either car, you'd probably be better off moving the Tender to that spot and running a light-duty extension cord to power it. For instance, if the Tender is providing 3 amps at 13VDC (realistic float) and the Tender itself is 80% efficient, then the total power draw is around 49 watts. At 110VAC, that's less than 2.5 amps, no real challenge for even a light-weight extension cord.

If the above is not an option, then once again, Mr. Fluke is your friend with regards to your question. Install the Tender w/o using an extension on the output and measure the voltage being impressed across the battery. Then extend it and measure again at the battery. I'm not sure what an acceptable delta would be but I'd suspect not too much.

Good luck with your project.

For now, I've been placing the Tender in the walkpath. It's okay but inconvenient to walk around it. But fine for testing.

But I'm trying to put it in a more permanent location that avoids where we walk in the garage.

Another alternative may include the use of AC extension cords and mounting the Tender to the ceiling above the cars.... Hmm, maybe mount it to the garage door opener....?

I own a 1953 Dodge M 37 24 volt military truck. I have for the past 10 years used 2 battery tenders to keep the batteries charged. No problems yet. I have replaced the batteries 5 years ago and they are still taking a charge, I just have to maintain the battery acid.

The tender reads battery voltage and charges based on condition.
Using only one on two different battery’s at the same time is a no go.