new digital duo charge......by balmar

[bigbad4cyl]

http://www.balmar.net/page20-Duocharge.html ; this is what im looking at for my situation......i have a optima starting battery ...and will be using two 6 volt golf cart batterys as the house bank............it fits the bill saying it handles two different battery types ...............how ever in the description it says connect as usual ,when house battery charge excedes 13 volts ,a regulated current of up to 30a brings the start battery to full charge.......................ok my problem understanding this is ........what if my house batterys have drained essesivly and cannot be recharged for at least 2 hours .......that means with this unit my starting battery wouldnt see any current for over 2 hours or longer ..........that is kinda wrong isnt it .......shouldnt the starting battery be charged first if anything...........

 

[LubeDude]

Re: new digital duo charge......by balmar

This shouldnt be a problem as your starting battery likely will never drop low enough to not start your engine. Make sure that your charger will only charge your Optima at a low rate, they do not like being charged for extended periods over 3 amps. This is not normally a problem as they are just charged for short periods after starting, the red top is "NOT" a deep cycle, and even the deep cycle needs to be charged slowly.

 

[Dunaruna]

Re: new digital duo charge......by balmar

I see your point bigbad. I have a pulse isolator that charges the motor battery (main) first and then when it reaches a certain voltage (programmable) it starts charging the house banks, if the main batt falls below a certain voltage (also programmable) the isolator stops charging the house banks and starts charging the main batt - the bottom line is that the main batt is always first in line for a top up. The isolator in your link does it the other way, strange. BTW, if it stops charging the the house bank at 13v then they won't be fully charged.<br /><br />So whats stopping you from simply connecting the wires from the isolator visaversa so that the main batt gets fed first and foremost?<br /><br />How much is this unit?<br /><br />Aldo

 

[bigbad4cyl]

Re: new digital duo charge......by balmar

i thaught the same thing but i work from 5;30 in the morn till 6 pm 6 days a week ....and i dont do cell phones.....and i drive a big dirt truck....so i have no way of contacting any tech suport .....the west marine guys just look at me and always say call tech support.............it costs 169? .....and i thaught about hooking it up reversed like you say...but i got to ask first ....and the link to the product pdf never works in that ad......duna runa how much is a pulse isolator

 

[bigbad4cyl]

Re: new digital duo charge......by balmar

i also have a balmar external reg that sences voltage at the battery[one of the bat] i can set the charging voltage with it ,,,and it soft ramps up and down etc.....I was thinking of using a normal isolator with it but it is only able to sence 1 battery so i could be over charging one bat while recharging the other [right?]

 

[Dunaruna]

Re: new digital duo charge......by balmar

My isolator came in a package deal with lots of other toys so I don't know how much it was - I'll check (somewhere in the dark recesses of my brain I'm thinking $100.00 but its a guess). I agree that talking to their techs is the next step, be interesting to know WHY they have set it up that way. Lubedude makes some good points but IMO I like to ensure the starting battery is kept full first, after all, the house batteries won't cause you to be stranded - in the dark maybe - but not stranded.<br /><br />Aldo

 

[Don S]

Re: new digital duo charge......by balmar

The best thing to do is get away from using an isolator completely and go to a charge relay, battery combiner, voltage sensitive relay, (They have many different names)<br />I installed one on my boat with 3 on/off battery switches for controlling house and starting current. Now when I start my engine, full charge goes into my starting battery till it reaches 13.7 V then the relay engages allowing amperage to go to the house battery also. In this way the start battery is always able to start the engine and with the 3 switches I cannot accidentally run down my start battery.<br />Here's the system on my boat.<br /><br />

 

[bigbad4cyl]

Re: new digital duo charge......by balmar

that looks great don s ..however i am using two different types of batterys [wet],[optima]....and i was just trying to be nice to the optima...................im thinking of using the <br /><br />voltage regulator with the sencing probe [just wondering wich battery to hook it to......,and a combiner ............what if i keep pumping 13.7 volts into the optima all day will it hurt it .....once it reaches 13.7 does it need to be shut off.............what voltages do optimas,,,,and wet batterys like............why cant some one design somthing logical

 

[Don S]

Re: new digital duo charge......by balmar

You shouldn't have any voltage problems between the optima and regular flooded batteries, the problems arise with Gel cell batteries which operate on a lower voltage. the problem with battery isolators is they work on diodes, and diodes cost you around a volt. (either .6 or .9 don't remember which). It's common to put a diode in the alternator sensing line in order to fool the alternator into not seeing the voltage drop in the isolator (Diodes).