The Deltran will test the voltage of the battery when first plugged in, if below a pre-set voltage the tender charges to another preset level. When that level is reached the charge stops and the batt. voltage is monitored. If the voltage falls below the preset level the charge kicks in and the process continues, keeping your batt. at approx. 13.2v. I've used a Deltan product since 1999, their warranty is excellent.

 

AGM or lead acid?

 

You should get outside of the house once in a while and learn a few things about batteries and the use of battery tenders.

 

When I leave on an extended trip and I'm not taking the bike or hot rod, I plug the battery tenders into a lamp timer. Run the timer a few hours a day and they're good to go when we get home.

Ray

 

My mistake I was thinking trickle charger. The irony of your post is I was already outside ( well standing in line at a store ) when I did my intinal post

 

AGM. It was the Harley 65958-04.

 

Battery tenders charge the battery to a certain level and then just monitor the battery voltage. The only thing I found wrong with a battery tender junior, I had on the bike, was that the battery voltage would fall and the tender wouldn't go back into the charge mode to replace the juice that had been lost. I personally do not know how much loss has to take place before it will kick back into charge mode. If you don't believe that this actually happens, just go into the garage and unplug your tender and then reconnect it to your bike. Yeah, I know that the voltage drop isn't very steep but at times it took awhile to get it back to fully charged.
Fast forward to a couple of years ago, and I started hearing great things about another brand of charger/maintainer. So I bought 1 and it is a lot more responsive to what is going on with the bike than my previous one.
If I walk over to the bike, and punch the mileage button, the new maintainer will come on and starts to charge. It also can charge up to 5 amps and has a mode to keep the battery from freezing in really cold weather. So now I have 2 of them and the tenders always go straight to fully charged when I plug them in.
BTW Both installed batteries are AGM.

 

How many miles during those 10 years?

 

It appears that there are many that don't read the owners manual that comes with a tender.

First they are for lead acid and AGM batteries only.

2nd any instruction for any other type battery such as Li or Ni Cad has nothing to do with the type battery the tender is intended for.

3rd they are not remotely like a trickle charger that if left on too long will fry a battery.

Tenders highest and best use is to plug them in only disconnect them to go on a ride then plug them back in when returning.
The microprocessor knows everything relating to the status of the battery instantly. It does not need to "think about it". It can detect if the battery is sulfated and begin a process to dissolve it. No other system can do it.

The life of a new battery is limited by the number of times it can be charged and discharged. The tender used as instructed keeps the battery @ full charge then "floats" the battery at about 0.005 volts which is about what an installed drains at.

A battery can last 6 to 10+ years that way. How ever even the identical model of battery made in the same plant can have different life capacities due to built in defects. The connections between cells can fracture from vibrations/impact shock. Other defects may be in the battery.

As a collector of vehicles over several decades that started in the past with just recharging a low battery on a charger then latter when they came out with trickle chargers which took effort to manage each each day the introduction of tenders was amazing.

I currently have 25 in use. On average a vehicle spends a year on a tender before being used. The longest was three years Never a single failure

If your battery runs down with one one check the connections because they aren't connected. The series of red, green and yellow lights will communicate what is going on. Well if you read the manual anyway.

 

I bought in in 2015 with 5,900 miles. Since then I put 16K on it, and an educated guess would be around 1,500-2,000 starts.