Calling on Optima Red Top experts

[foxfire42]

I wish I had one of those simple meters that Tom Wesenberg posted.

I searched for Optima problems but found nothing like the problem I have. I hope it something simple like my eye sight. I have two Optima 6V Red Tops. I charged them on a 6V Battery Tender. I also have a Napa 6V battery I charged with the Tender.

I accidentally stepped on my Harbor Freight free meter so had to use the one with way too may settings. I went to check the voltage on the Optima I was going to install and the darn thing read 17V. Thinking it was my eye sight as I've only had my one eye de-cataracked so far I checked my Napa battery.....6.4V. In disbelief I rechecked the Optima and also checked the other one and BOTH read in the 17+V range.

Now is this possible

[Big hammer]

3 times the volts needed? Electrons are wanting to get out! Can't wait for the experts!

[super flat]

Are you checking them when the charger is charging them? Gary

[Mike V. Florida]

Bad meter or wrong meter setting.

Have a pic of the meter?

[foxfire42]

I have it set on DCV. I did not change the setting but used the same setting for both measurements. The Optima reads 17.1 and the Napa reads 6.2

Here's a picture of the meter and the batteries. Like I said I only have this fancy meter and not real good at setting it properly. With an appropriate reading on the Napa and the bazaar reading on the Optima I'm assuming the meter is set correctly.

[jax55]

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Put a headlight or something across the battery to take the surface charge off and see if it changes. No load on the Optima but the Napa appears to be installed in the car.
Might make a difference in the readings.

[foxfire42]

JAX55, I'll try the load on the Optima and see what happens. You're right, the NAPA battery is in the A but I checked the voltage on it before I installed it as I was going to install the Optima originally.

[Ulysses6]

is the photo on the left reading millivolts dc and the one on the right reading volts ?

[jmeckel]

Originally Posted by Ulysses6

is the photo on the left reading millivolts dc and the one on the right reading volts ?

Hard to tell as the picture of the display is not great, but I think it looks that way also, one is volts, one is millivolts. Which would mean the Optima battery is not charged.. as in dead.

[BILL WILLIAMSON]

I "think" I read somewhere, to charge a DEAD Optima, hook it in parallel with a charged up lead acid battery?? Go to Optima's website to make sure!!
Bill W.

[waxhead]

Yeah, looks like the Optima is reading - 17.1 milli Volts to me also, which as stated above, means that it is not holding any charge. (Unless there is a bad connection in your meter leads or some other problem)

[foxfire42]

OK now I feel STUPID and embarrassed. Out goes that meter, unless someone wants it. I'm going shopping for a nice simple meter that's "fool" proof (me being the fool of course). I don't know how the meter changed settings since I took the Optima reading again to make sure I read it right. Then I walked out front and put the meter on the Napa battery. How could the meter change settings from the garage to the carport????

Maybe I'd have seen the M if my other cataract had been done.

[Mitch//pa]

you accidentally pushed one of the buttons switching the scale

[Bob C]

It says on the meter under the selector switch "Autoranging"
it selects the proper range automatically.

Bob

[jmeckel]

Nothing wrong with the meter, just remember to read the scale. You will have issues with any meter until you get used to reading what it is telling you, or in the case of a fully manual analog meter (for example Simpson 260), you will either burn it out or learn to operate it. I do not mean to be disrespectable here, just stating the facts. In Electronics we leaned how to build and repair analog meters as well as calibrate them. This was a good thing because there was a lot of them burned out by students not remembering how to properly set the scale for whatever was being measured. We used a lot of Simpson 260 meters, there was a time when we all could fix them in a few minuets.

[J Witt]

An open circuit Optima 6V battery (no loads) should read about 6.7 Volts. In spite of their construction, they are still lead acid cells in chemistry and result in the same voltage ranges as other lead acid cells. That is from about 10 volts functionally dead to about 14.5 volts at max charge. The construction gives the Optima battery very low internal resistance, which makes them good for high burst currents and rapid recharging.

Be aware that almost any lead acid cell (even mostly discharged ones) can make 800 to 1000 amps if short circuited, making for a dangerous situation.

Some safety tips when working on your battery:

Wear safety glasses.

Remove the chassis terminal first and cover the battery post with some kind of insulator -- I keep some of those plastic caps the battery came with.

No wrist watches, bracelets and especially, no finger rings. If you short circuit one of those you can have an instant third degree burn all the way around your arm or finger. Bad deal!

John

[Mike V. Florida]

What kind of charger are you using?

OPTIMA® REDTOP® Charging Information

The following charging methods are recommended to ensure a long battery life. Always use a voltage-regulated charger, with voltage limits set as described below.
REDTOP® Type: 6V
These batteries are designed for engine starting applications. They are NOT recommended or warranted for use in deep-cycle applications.
Recommended charging information:
Alternator:
6.65 to 7.5 volts, no amperage limit.
Battery Charger:
6.9 to 7.5 volts, 10 amps maximum, approximately for 6-12 hours.
Rapid Recharge:
Maximum 7.8 volts (regulated), no current limit as long as battery temperature remains below 125°F (51.7°C). Charge until current drops below 1 amp.
Float Charge:
6.6 to 6.9 volts, 1 amp maximum current, time indefinite (at lower voltage).

Strictly adhere to all limits.