Battery Tender jr not good?

[abusive throttle cranker]

I bought a Big Crank ETX-18 for my 1st gen. When I received it I wasn't ready to install so I thought to put it on the battery tender. Ya I know its supposed to be full up and ready to go. But what the heck right? And when the green light comes on I can be assured its full up. Well......it was on charge for 1.5- 2 hrs and the light is still red. I went over and touched it and the battery tender was HOT! Not hot enough to keep from grabbing it to remove from the wall but close. So- isn't the battery tender jr compatible with AGM tech? Its lead/acid right? Do I need a special purpose charger?

[midnightventure]

The Battery Tender Jr is a maintainer. If the battery was way down the junior would be pushed to provide the amperage needed to bring it to full charge.

[XV1100SE]

I don't believe the Junior supports AGM batteries.

Canadian Tire has the Plus at 25% off and DEFINITELY supports AGM batteries.

[Prairiehammer]

I don't believe the Junior supports AGM batteries.

Canadian Tire has the Plus at 25% off and DEFINITELY supports AGM batteries.

 

Battery Tender website says the Jr. is for AGM.

 

http://batterytender.com/battery-tender-junior-12v-at-0-75a.html

[XV1100SE]

When I read the packages in the store I didn't see AGM on the Jr... it did mention "only for lead/acid".

 

The Plus specifically indicates AGM on the package. That's what I based my purchase on... plus the wiring to connect permanently to the battery.

 

I see on the Canadian Tire (CT) description of the Plus says :

"Perfect for charging and maintaining all 12V lead-acid batteries including AGM and gel cell"

and the Jr says :

"Perfect for maintaining all 12V lead-acid batteries including AGM and gel cell"

 

Plus is on sale at CT for $50. http://www.canadiantire.ca/AST/browse/4/Auto/3/Batteries/BatteryChargers/PRD~0111941P/Battery+Tender+Plus,+1.25A+Charger%2BMaintainer.jsp?locale=en

 

The Jr. is on sale for $30

[Brake Pad]

got the answer, (CHECK THE FUSE ON THe IN LINE) maybe burnt out or damaged

[Snaggletooth]

I've been getting several bikes ready for the season lately and dug out my Tender Jr. to charge a few up. This is what I'm seeing.

 

As stated the Tender Jr. is NOT a charger. For a serverly discharged battery they will not bring it back to a full charge. Not designed for that. With batteries just needing to be topped off they work fine.

 

I'm seeing similar results with both L/A and AGM's during the top off process.

 

The Tender I use is 750ma's. The indicator lights show as they should during the charge according to instruction. I'm using a muiltimeter and a digital voltmeter to monitor the charge voltage using the Tender.

 

With a low battey of either type the Tender is showing at 14.5 volts during the initial charge then dropping to 13.2 volts as it tops off in the float mode. That's as it should be. They dont shut off, just maintain a charge.

 

With a severly discharged battey of either type the Tender will charge over a longer period of time. 24 hours or more. BUT.... what I'm seeing is with the Tender only charge the displayed volts will not hold and drops much quicker sitting dormant after the charge.

 

Using a regular battey charger first to bring the battery to full charge gives the battery a deeper charge and holds the voltage stable for a longer peroid of time sitting dormant.

 

All I know is what I've been told by battery supplier and what I've read. The AGM's reguire at least 14.5 volts to charge propery. The Tender does do that.

 

My Tender does get warm on some batteries, but never hot to touch. Never blown a fuse on it either.

[Prairiehammer]

Larry,

Although the AGM SHOULD have come with a decent charge, the instructions that came with mine said to charge it if the voltage was less than 11.5 volts. It also said to use a 2 amp charge rate for 12-14 hours or until the voltage was above 12.75. Only then should a maintainer be used.

Another thing I have read on the forums concerning the maintainers: many will NOT charge if the battery voltage is less than 9 volts. One must charge that battery with a conventional charger to bring the voltage up into the operating range for the maintainer.

I accidently discharged my AGM last summer because I left the trunk open on the '90. When I discovered my mistake the AGM was less than 2 volts. Researching the internet I found that the AGM must be charged from that low voltage with a NON-automatic charger as most automatic chargers will not charge if it senses such a low voltage. I charged the nearly dead AGM with an old Schumacher manual charger for a few hours at 6 amps. Put the maintainer on when the voltage was about 12 volts and let 'er cook over night. Next morning, battery voltage was 13.7 volts. That discharged AGM has performed as new ever since.

Have you checked the output of the Junior? Have you taken a voltage reading on the AGM?

[abusive throttle cranker]

I'm sorry- I didn't make myself clear. This battery of which I speak is brand spankin' new. I put it on the tender just to make sure it was topped off as I'm not yet ready to install it the battery box/coil tray/valve covers etc all removed from the bike. And no- I have no electrical tester. As a matter of fact I am working with an absolute minimum of tools. The 7.5amp fuse in the tender line appears good. The unit plugs into the wall so there is no input line. Is there a fuse inside the tender jr itself?

[straycatt]

According to Deka (East Penn) there is more to charging a VRLA (Valve Regulated Lead Acid) battery than just xx number of amps. Temperature, and degree of charge have a lot to do with it as well.

 

From the Deka website, everything you could possibly want to know about VRLA (AGM) batteries.

 

http://www.dekabatteries.com/assets/base/0139.pdf

 

There's lots more, but here is a taste...

 

How do VRLA batteries recharge?

Are there any special precautions?

While our VRLA batteries accept a charge extremely well due to their

 

low internal resistance,

any battery will be damaged by continual

under- or overcharging. Capacity is reduced and life is shortened.

Overcharging is especially harmful to any VRLA battery because of

the sealed design. Overcharging dries out the electrolyte by driving

the oxygen and hydrogen out of the battery through the pressure

relief valves. Performance and life are reduced.

If a battery is continually undercharged, a power-robbing layer of

sulfate will build up on the positive plate, which acts as a barrier

to recharging. Premature plate shedding can also occur.

Performance is reduced and life is shortened.

Therefore,

it is critical that a charger be used that limits voltage.

The charger must be temperature-compensated to prevent underor

overcharging due to ambient temperature changes.

(See Charging

Voltage vs. Ambient Temperature chart on page 11.)

Important Charging Instructions

The warranty is void if improperly charged.

Use a good constant

potential, temperature-compensated, voltage-regulated charger.

Constant current chargers should never be used on VRLA batteries.

How critical is recharge voltage?

Why are all VRLA batteries so charge

sensitive?

All lead-acid batteries

give off hydrogen from the negative plate

and oxygen from the positive plate during charging.

VRLA batteries have pressure-sensitive valves. Without the ability

to retain pressure within the cells, hydrogen and oxygen would be

lost to the atmosphere, eventually drying out the electrolyte and

separators.

Voltage is electrical pressure. Charge (ampere-hours) is a quantity

of electricity. Current (amperes) is electrical flow (charging speed).

A battery can only store a certain quantity of electricity. The closer

it gets to being fully charged, the slower it must be charged.

Temperature also affects charging.

If the right pressure (voltage) is used for the temperature, a battery

will accept charge at its ideal rate. If too much pressure is used,

charge will be forced through the battery faster than it can be

stored. Reactions other than the charging reaction occur to

transport this current through the battery—mainly gassing.

Hydrogen and oxygen are given off faster than the recombination

reaction. This raises the pressure until the pressure relief valve

opens. The gas lost cannot be replaced. Any VRLA battery will dry

out and fail prematurely if it experiences excessive overcharge.

Note:

It is the pressure (voltage) that initiates this problem—

a battery can be “over-charged” (damaged by too much voltage)

even though it is not fully “charged.”

This is why charging voltage must be carefully regulated and

temperature compensated to the values on page 11.

 

 

[kevin-vic-b.c.]

no a battery tender will not charge a "dead" battery.

[Snaggletooth]

I'm sorry- I didn't make myself clear. This battery of which I speak is brand spankin' new. I put it on the tender just to make sure it was topped off as I'm not yet ready to install it the battery box/coil tray/valve covers etc all removed from the bike. And no- I have no electrical tester. As a matter of fact I am working with an absolute minimum of tools. The 7.5amp fuse in the tender line appears good. The unit plugs into the wall so there is no input line. Is there a fuse inside the tender jr itself?

 

The Tender Jr. only has fuses on the two links that can be plugged into the main lead.(one with lugs to the battery terminals and second one with the clamps.)

 

Nothing internal, of anything that can be checked that I know if.

 

The only way to be sure of finding the problem would be checking the volts directly off the battery and again off the Tender with a meter. Or if you have a head light handy jump the light connections from the Tender clamps and see if it lights up. Then jump the plug from the Tender to the head light. See what happens.

 

I've never seen an AGM dead to the bone out of the box. Not impossible but with a DEKA, I'd be surprised. But it's possible.

 

And you're right the solid red shuold indicate the battery is charging. The solid green shows fully charged.

 

But HOT! Something ain't right. But the Tender you have will be fine for the AGM but once you find your problem I doubt you'll ever need it. My ETX18L is going on five years old and never been charged. Never dropped low enough to worry about it.

[Brake Pad]

no a battery tender will not charge a "dead" battery.

 

it will take 4 days, but it will recharge a battery. I did it with mine

[abusive throttle cranker]

Yeah the temperature of the thing is what got me. And I have been using this BT to maintain the 1 yo WestCo battery in my (just sold) Suzuki VL1500. In which app it worked fine! And recently too- 3 days ago!