Join Date: Jan 2003
Location: Maine Coast
Thanked 287 Times in 220 Posts
Rep Power: 17
I would not call battery combining relays "inferior" just one of many options and not necessarily the absolute safest or best method.
I have used combining relays on my last four boats and never once had any issues with them. I stayed away from the Balmar Duo Charge only because I have personally had three of their voltage regulators fail on me and they don't stand behind the product so I no longer buy Balmar stuff.
I really do like the concept of either the Echo Charge or the Duo Charge and have installed both but the Duo needs to be re0-set if the bank needs more than 30 amps charge current..
I think on my next upgrade, if my Yandina combiner ever dies, I may install an Echo Charge as I never ever use my start battery so it would not be pulling much if any load off my alt or perhaps 1-2 amps at best.
Comparing ACR type relays to an Echo type charger is like comparing a Toyota to a Lexus. The Toyota is a great product but the Lexus just takes it to the next level..
The Echo Charger is relatively closely priced to combining relays but the Balmar Duo is more..
Here is a far fetched scenario where an ACR type relay could be an issue.
#1 You accidentally deplete your AGM house bank by leaving the fridge on over night after being on the hook for the last three days.
#2 You switch to the start battery and fire up the engine. Good thing for start/emergency batteries.
#3 Once the alternator ramps up the ACR relay combines both banks and the start battery, being nearly fully charged, now equalizes voltage, or attempts to, between the very large house bank and the start battery. Because they are AGM this process of equalization can happen very quickly due to acceptance
#4 You motor out of the anchorage and realize you're not spitting any water out of the engine exhaust so you drop hook, shut down the motor and clean the sea strainer.
#5 You finish cleaning the sea strainer and go to start the motor but all you get is click, click. This is because your group 24 battery with roughly 70 amp hours just tried to charge a 450 amp hour bank of dead AGM batteries and now the entire system is at about a 10% charge, mostly dead and unable to supply the 160+ cranking amps needed to start the motor. The short run time and the resulting alt output from this short run time was not enough to overcome the dead house bank enough in the short duration you ran the motor..
Again, far fetched but this could happen and Murphy is always waiting...
With an Echo charger this would not happen. Both are safe and both system work well.
-Maine Sail / CS-36T
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
© Images In Posts Property of Compass Marine Inc.
Last edited by Maine Sail; 11-09-2010 at 04:26 PM.