IOTA Battery Charger Question

eherlihy · #1 11-02-2010

Situation:

Because it was very favorably reviewed in this forum, I purchased an IOTA DLS 30 Battery Charger with the built in IQ4 circuit. (follow links for manufacturer's information)

I can see that it is a good battery charger. However, what wasn't mentioned to me is that this charger is set up for a SINGLE bank of batteries. It also does not feature temperature compensation or have an AMP OUT meter - as required by ABYC. In fact, this battery charger is aimed at the RV market, and not the boating market.

The IOTA also cost 1/2 of what a similar Victron would have

The Victron, however, has an AMP meter, supports 3 banks, and supports temperature probes

. I cannot return the charger, and I don't want to lay out another $350 for a Victron. (at least not now)

My new to me boat has 2 banks; a starting battery, and a house. The house is a relatively new Trojan, and the starting is a WM special. Connecting the IOTA to both banks in parallel will most likely leave the house bank perpetually under charged, as the starting battery comes up to charge more quickly than the deep cycle Trojan.

Test:

I needed to charge the house battery, so I brought it home and hooked it up to the charger on the workbench. Initially the IQ4 blinked rapidly indicating a bulk charge. So far, so good.

After a minute, I moved the charger. Because I didn't tighten the terminal screw enough, one of the DC leads pulled out. I noticed that the charger switched to float charge mode. I re-inserted the DC lead, and the charger STAYED in float charge mode.

OK - I thought, "I'll cycle the AC power to get it back into bulk charge mode." WRONG! I pulled the AC plug, waited about 30 seconds and the IQ4 stayed in float mode (I presume because it was connected to the battery). I re-inserted the AC plug, and it stayed in float mode.

I ended up disconnecting both the AC, and the DC from the IOTA, waited 10 seconds for the IQ4 LED to go out, and then re-connected the DC, then the AC, and it started the bulk charging cycle again.

Problem:

My working theory is that the IQ4 circuit seems to want to be reset by removing all power before it will change modes.

Work-Around?

I'd like to bounce this idea off the forum to see if I can make use of the IOTA and not fry, or under charge, either battery. My thought is that I could run the output of the IOTA to the common terminal of the "1, both, 2, off" battery switch. When I want to charge the house bank, leave the switch in the house (2) position, and when I want to charge the starting battery, leave the switch in the starting (1) position.

Therefore, to charge on the boat I believe that I will need to:

Shut off the battery charger breaker on the AC panel
Turn the battery switch to OFF
Turn the battery switch to the bank that I wish to charge
Flip the battery charger circuit breaker to ON

To change banks, I will need to repeat this entire switching process.

This is a little more complex than I would like, but I think that it should work....

Comments???

Maine Sail · #2 11-02-2010

Get an ACR (voltage sensitive relay) or an Echo Chager and the Iota will charge two banks just fine plus you'll gain all the other benefits of "behind the scenes" charging of both banks. If you add an Echo Charger you will need to route your alternator output and Iota to the house bank, which is a good idea anyway to prevent fried diodes..

As for ABYC A-31 it reads:

31.5.2.2 A battery charger shall be provided with an
ammeter or an alternate indicator of the output current
or charger output status.

The Iota with IQ4 has an LED that tells you the charger output status.

LED ON = Float
LED Slow Flash = Absorption
LED Fast Flash = Bulk

If the IOTA is connected to the bank and the bank was recently receiving a charge current then the surface charge is high enough to make it think it needs float voltage when it comes back on this is why you don't want to interrupt the charge. Let the battery rest for a while, or as you found out disconnect it from the bank, and it will start back up in bulk mode if the surface charge has been wiped.

I personally dislike "multi-bank" output charges that don't allow options for single bank config as they more often than not divide the amperage between two or three banks meaning that 30 amp three bank charge is often really three 10 amp chargers when connected to three banks.

P.S. Congrats on the new boat, what is she?

arf145 · #3 11-02-2010

Even when an item is favorably reviewed here, it's a good idea to check out the particulars. Even a casual review of the Iota online would show that it has no meter and mentions no temperature compensation or multibank capability.

Setting it up as Mainesail suggests, which is what I did, uses the Iota to its best advantage.

sailingdog · #4 11-02-2010

I'd second what MS said about multi-bank chargers. Most are pretty pathetic units and not worth the extra money they cost. Also, if you're really concerned about getting the info from the battery charger, buy a good battery monitor, like a Victron BMV 601 unit.

eherlihy · #5 11-02-2010

Excellent! Thanks guys (and 'Dog.)

[EDIT]
Actually, no one has yet commented on the problem, or my work around.

Since there is experience with this charger here, has anyone else noticed that it needs to be disconnected to reset. Was I simply too impatient...

What did I miss?

Maine Sail · #6 11-02-2010

Quote:

Originally Posted by eherlihy

Excellent! Thanks guys (and 'Dog.)

[EDIT]
Actually, no one has yet commented on the problem, or my work around.

Since there is experience with this charger here, has anyone else noticed that it needs to be disconnected to reset. Was I simply too impatient...

What did I miss?

You must have missed my post. The charger monitors both line and DC voltage. Not just one or the other. Both apparently need to be disconnected to re-set it. If still connected to DC, but not AC, and a recently charged battery and disconnected/re-connected, it WILL read the surface charge while the unit is off and upon return may go into float mode.

Simply disconnecting the line voltage does not change the fact that you may still have a high DC voltage from surface charge therefore forcing it into float. I would rather have it fire back up in the safer float mdoe than equalize or bulk if it feels it may not need it.

I like the Iota, they are built like tanks but they have their limitations. they are a great charger for the PRICE. I have no problem using them on wets but do not use them on AGM's, gels or in situations where I need a custom charge profile or temp regulation.

eherlihy · #7 11-02-2010

Correct... I missed the paragraph on surface charge.

Thanks again!!