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myster 10-10-2008 05:15 PM

Echo Charge drawbacks?
 
I've seen the Xantrex Echo-Charge battery charger device highly recommended on this site as an alternative to a battery combiner relay. I have several questions about them:

1) The manual for the echo-charger says it has a no-load current draw of 50 milliamps (as opposed to 12 milliamps for the Blue Sea combiner relay). For someone who doesn't leave their boat plugged into shore power regularly, should this be a concern? This will drain down a 260 AH battery bank to 50% in a little over 100 days. I'm not suggesting that anyone would want to go that long without cranking the engine, or plugging into shore power - BUT, it still concerns me that there is a constant drain on the batteries. (I don't have any system to trickle charge my batteries yet - apart from leaving it plugged in to shorepower, which I try to avoid).

2) The recommended setup for the echo charge is: direct all charging to the house bank (alternator and shore power charger), then the echo charge will charge the starting bank when it senses >13.0V on the house batteries. What if you have a severely depleted house bank? Wouldn't the house bank pull all the current from the alternator, leaving the starting bank with no current until the house batteries get back to 13V? (am I not understanding this correctly?)

3) How do you test that the echo-charger is functioning? With a combiner, you can test the voltage of each battery bank....when they're combined, it should be similar, right? How can you tell that the echo charger is working?

Thanks for any info you can provide. I'm just about to install the echo-charger, but am wondering if I should exchange it for a Blue Seas ACR.

camaraderie 10-10-2008 05:56 PM

1. A wet cell bank of 260 amps will draw itself down by more than that each day. If you have a concern about leaving the boat unattended and without shore power for long periods of time, I would suggest a 20 watt solar panel to keep things topped off.

2. Once the alternator starts charging...the echo charge will sense over 14V rather than the actual state of charge of the house bank. So...both will be charged with the alternator on.

3. Suggest you get a voltmeter or Link system to monitor each bank. From my point of view, I don't care to monitor my start battery as it uses so little current and can thus be checked infrequently as long as I KNOW that my house bank is in good shape...'cause I can always start with my house bank if there is a problem. Still...a small voltmeter is cheap and easy to install if you need that assurance.

Go with the echo charge!

denverd0n 10-13-2008 01:55 PM

Quote:

Originally Posted by myster
Wouldn't the house bank pull all the current from the alternator, leaving the starting bank with no current until the house batteries get back to 13V? (am I not understanding this correctly?)

This is the part of the whole Echo Charge thing that has always seemed backwards to me. In my mind it makes more sense to charge the starting battery and then the house battery. First and foremost, no matter what else happens, I want the starter battery fully charged so that I can always start the engine whenever I need to. Then, after that is covered, charge up the house bank with whatever excess current you have available. That's how it makes sense to me.

Okay, so maybe I've got this all backwards. I've had people tell me that I do, and they've explained why, but the explanations never quite added up to me. Still makes sense to me that you would want to charge the starting battery first, and the house battery after that.

travler37 10-13-2008 02:07 PM

Sense to me to
 
Quote:

Originally Posted by denverd0n (Post 383464)
This is the part of the whole Echo Charge thing that has always seemed backwards to me. In my mind it makes more sense to charge the starting battery and then the house battery. First and foremost, no matter what else happens, I want the starter battery fully charged so that I can always start the engine whenever I need to. Then, after that is covered, charge up the house bank with whatever excess current you have available. That's how it makes sense to me.

Okay, so maybe I've got this all backwards. I've had people tell me that I do, and they've explained why, but the explanations never quite added up to me. Still makes sense to me that you would want to charge the starting battery first, and the house battery after that.

I have allways thought the same.Just wire it up so it thinks "house" is actually the start.Am leaning more towards multy alts and banks presently.

Mark

k1vsk 10-13-2008 03:27 PM

Denverdon

Reversing the eco-charger could have the unintended consequence of over-charging the start battery, leading to a premature death usually when you will most need it.
Reversing the charge scheme (putting the Eco-charger on the house bank) would severely limit the rate at which the house bank would charge.

The purpose of the Eco-charger is to ensure the start battery is not cooked as without it, the start battery would be charged at the same rate as the house bank. If, as most of us do, you have a large house bank, large charging source and a somewhat depleted house bank, the net flow of current into the house bank would be at a rate such that the start battery (presumably not equally discharged) would suffer.

In most respects, every boat should be able to start off a house bank if necessary. There is nothing sacred about a fully charged start battery as long as you have a means of switching over to a house bank for starting when needed.

travler37 10-13-2008 04:28 PM

Quote:

Originally Posted by k1vsk (Post 383507)
Denverdon

Reversing the eco-charger could have the unintended consequence of over-charging the start battery, leading to a premature death usually when you will most need it.
Reversing the charge scheme (putting the Eco-charger on the house bank) would severely limit the rate at which the house bank would charge.

The purpose of the Eco-charger is to ensure the start battery is not cooked as without it, the start battery would be charged at the same rate as the house bank. If, as most of us do, you have a large house bank, large charging source and a somewhat depleted house bank, the net flow of current into the house bank would be at a rate such that the start battery (presumably not equally discharged) would suffer.

In most respects, every boat should be able to start off a house bank if necessary. There is nothing sacred about a fully charged start battery as long as you have a means of switching over to a house bank for starting when needed.

So the dunb newbi needs something explained to him,
Way i understand this the charger charges one bank to max the kicks to the other.How does that fry a start batt if you reverse it?
Thank You
Mark

k1vsk 10-13-2008 05:30 PM

A better explanation can be had by reading the mfg web site description, a portion of which is quoted below.

I highlighted the relevant part:

"Xantrex’ digital echo~charge (part#82-0123-01) is designed to charge auxiliary or starting batteries from an inverter/charger or other charging source with limited voltage drop. The Xantrex echo~charge detects when the house battery bank is being charged and directs a portion of the charge current to auxiliary or starting batteries. The maximum charger current offered by echo~charge is limited to 15 amps.
  • 15 A maximum charge current
  • Automatically switches on/off without affecting the in-house battery bank or over-charging
  • Utilizes excess current from the primary charging source"
The start battery should never be discharged significantly and could cook while the house bank gets charged slowly.

btrayfors 10-13-2008 07:02 PM

As K1VSK said, it makes no sense at all to reverse the EchoCharge device. Among other things, you'd limit your charge on the house batteries to no more than 15 amps (the capacity of the EchoCharge), even if you had upwards of 100 amps available for the house batteries. Dumb, for sure!

Cam said it well, but it bears repeating: starting batteries require very little charging. They only draw a miniscule amount of power when starting the engine (lots of amps but only for a few seconds). Typically, this power is replaced in just a few minutes after you start the engine. After that, what's the alternator to do? Idle?

EchoCharge devices will typically begin sampling and charging the start battery when the voltage exceeds about 12.8. It doesn't have to be 13.0 or more. Furthermore, the charging voltage on your house batteries will reach that threshold very soon, even if they're badly depleted. Remember...it's not the resting voltage of the batteries which causes the EchoCharge to activate; it's the charging voltage. That will reach the necessary 12.8V in just a few minutes after the engine starts and the alternator begins charging the house bank.

Finally, the 50mil draw on the house batteries is for all intents and purposes negligible in a properly designed system. As Cam correctly pointed out, if you anticipate being off shore power for long periods of time, you must provide some other charging source (solar panels, wind generator, etc.) to keep your batteries topped up, otherwise you're gonna kill your batteries through sulfation, stratification, and the other ills which attack chronically undercharged batteries.

Bill

Stillraining 10-13-2008 07:48 PM

But dont the chargers do this inherently on there own?

The specks in the truecharge 40 says that the voltage delivered to the three banks possible to charge at one time remains the same... but the current flow wont..as the majority of current flow go's to the most depleted bank..resistance is the key here not voltage. Im I wrong?

camaraderie 10-13-2008 08:57 PM

Still...you have SEPARATE hookups for charging each battery with the truecharge and MONITORING each battery and DIVERTING current as appropriate. With a single bank charger and no electronic testing and diverting, the TOTAL charge of ALL banks is all the battery charger sees...So... if you have a house bank of 200 amp hours and a 100ah starting battery and you are down 100ah's on your house bank but full on your starting battery...a STANDARD 3 stasge 40 amp charger will see the 300 amp hour total charge down 1/3 and apply a full 40 amps to the total bank...not 1 amp to the starter and 39 to the house.
A bit oversimplified...but that is the reason to use an echocharger if one doesn't have a really sophisticated charger like yours.


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