Hi

It should be close to 14 volts when they are charging. If it is lower then you have a problem. Make sure the charger has been on for at least 20 mins before you measure them. If the voltage is low, I subspect the charger is not up to the joke.

They PO on my boat did an excellant job installing the battery system. I look for his drawings and post them.

Nancy, what charger do you have? That is the very first thing we NEED to know for us to be able to help you.

If you haven't yet, I highly recommend that you download and read the Ample Power Primer from the technical documents tab, here: [url]www.amplepower.com[/url] You will find that claims that the voltage "[I]...should be close to 14 volts when they are charging. If it is lower then you have a problem...[/I]" is simply incorrect.

Mine is always above 13 volts on charge. Check each battery with a meter, but make sure the battery slector is not set to all. They should both read the same. My e-mail is [email]droopman_98@yahoo.com[/email]. If you want help e-mail me and we'll talk. I am an electrical engineer, or I was at one point in my life.

[url]http://www.windsun.com/Batteries/Battery_FAQ.htm#Battery%20Voltages[/url]

Battery charging takes place in 3 basic stages: Bulk, Absorption, and Float.
Bulk Charge - The first stage of 3-stage battery charging. Current is sent to batteries at the maximum safe rate they will accept until voltage rises to near (80-90%) full charge level. Voltages at this stage typically range from 10.5 volts to 15 volts. There is no "correct" voltage for bulk charging, but there may be limits on the maximum current that the battery and/or wiring can take.

Absorption Charge: The 2nd stage of 3-stage battery charging. Voltage remains constant and current gradually tapers off as internal resistance increases during charging. It is during this stage that the charger puts out maximum voltage. Voltages at this stage are typically around [B]14.2 to 15.5 [/B]volts.

Float Charge: The 3rd stage of 3-stage battery charging. After batteries reach full charge, charging voltage is reduced to a lower level (typically 12.8 to 13.2) to reduce gassing and prolong battery life. This is often referred to as a maintenance or trickle charge, since it's main purpose is to keep an already charged battery from discharging. PWM, or "pulse width modulation" accomplishes the same thing. In PWM, the controller or charger senses tiny voltage drops in the battery and sends very short charging cycles (pulses) to the battery. This may occur several hundred times per minute. It is called "pulse width" because the width of the pulses may vary from a few microseconds to several seconds. Note that for long term float service, such as backup power systems that are seldom discharged, the float voltage should be around [B]13.02 to 13.20 volts[/B].

I simply submit that "[I]Mine is always above 13 volts on charge[/I]" and [I]"...always above 14 volts. If it is lower then you have a problem..[/I]" are pretty much two different things. Important distinctions, I would say.

The description of the stages of charging are helpful.

Stu, we keep out frig on all the time. That keeps a load on the system and I notice my batteries are aways around 13 - 13.9 volts on charge, right where they should be. ;)

If you batteries are not at least 12.8 volts on charge, (after the ramp up time) you have a problem in the charging system.

Now... I supect the charger is not connected corrected or there is a load problem with the problem battery. Ihere could be a load that drains that battery down all the time. You could test if with a amp meter. I would consider installing a Links battery monitoring system.

Jimmy, you've now introduced yet another "number" in the charging routine: [I]"If you batteries are not at least 12.8 volts..."[/I]

The question Nancy asked appears to be about her charger's performance, rather than a question about "what is the correct process for charging batteries?" It seems to me that we ought to let Nancy answer first as to what her charger is, before we go off on a wild goose chase about how to properly charge batteries.

I completely agree with you that a battery monitor should be an important, if not first, piece of equipment. [I tried to save your fingers some typing time by providing the Ample Power link, because it has all that information. Some times folks don't read the links provided during these discussions, for some reason, and we end up repeating ourselves unnecessarily.] PWM -- our folks have found that it doesn't work. Proper charging and regular equalization (with wet cells only) is appropriate battery maintenance.

Nancy, are you still there?

Nancy,
It is really hard to offer any suggestion on your charger troubles, electrical de-bugging should only be done live and in person with a good meter.

But something you just said seems wrong to me. I have to repeat, wrong to me, it may be fine, but I have to mention it.

I have the same charger and batteries that you do but my charger is wired directly to each battery (positive) and (negative) terminal . I don't have any battery charger wires going to my master switch.

I would imagine all kinds of funny stuff can happen if you wire your charger to the master switch. I'd say take (1) red charger wire to one positive side of battery bank number one and a second red charger wire to battery bank number two. It doesn't matter which order or which red wires from the charger you use. Cover the end of your 3rd red charger wire with electrical tape.

Attach your single black charger wire to a black (negative terminal) wire on battery 1 [U]and[/U] to a black wire from battery number 2.

This (I believe) is the solution to your battery charger problems. Oh by the way, don't forget to set the little switch on the Xantrax charger for the type of batteries you have. (Wet cell, Gell cell, AGM cell)

Do your rewiring with shore power cord disconnected, check your work twice, then power up to shore.

good luck

Nancy, once again, what specific model of Xantrex True Charger? There is the older TrueCharge 20 or 40, the newer TrueCharge2 and the new XBM. Which one do you have?

There is really little difference in connecting the charger to the posts on the switch, as compared to directly to the banks, because it is simply the different end of the same wire! Most charger manufacturers recommend what Bill suggested.

That said, have you checked that the connections from the charger to each the banks, regardless of which end of the wire to the 1-2-B switch, is correct? (i.e., to the proper post on the switch - could be miswired to the B or common output post)

It is odd that you discuss using the switch in relation to battery charging. If you follow Bill's advice, and move the charger outputs away from the switch to the banks, that'd be a good first step, 'cuz then the switch is taken out of the equation. I assume from your description that you leave the fridge running, with the switch on 1.