Is the Blue Sea 7605 battery charger/isolator a good base for a simple dual battery system?

[James86004]

Just to add another datapoint, I installed the 7605 in our Dormobile since it had the ACR and charger in a small foot print, and space was a premium. It has worked well for two years. We have this, a combiner switch, and the starting and house batteries under the left front seat. Not much room for anything else. Also the alternator is a 65 amp Delco 10Si, which is an upgrade from the original 22 amp generator.

 

[Rico24/7]

Sounds like the OP found his Solution. I gained some insights from the Responses, yet, I’m still a bit confused on my Most Cost Effective, SAFE options for my (Jeep) Build. Simple solenoids are too .... Basic. VSRs (Voltage Sensitive Relays) don’t ‘manage’ the charging of two different battery types on one vehicle (I think). DC-DC Chargers ..... ? Smart Battery Mgmt .... pushing extreme limits of Budget.

Vehicle ~ ‘96 Jeep Cherokee XJ
Charging ~ Dodge 130A Alternator (?)
Batteries ~ BCI 51R AGM for “Cranking” BCI 34 Deep Cycle AGM for “House”
Battery Maintenance ~ Alternator when driving, (Possibly) Solar for Off-grid, AC “shore” power on INFREQUENT occasions.

Thoughts ? Blue Sea mentioned ? A CTEK option ? $400+ is simply out of a homeless person’s Budget ....

 

[DiploStrat]

This isn't hard, just a bit complex. Your comments suggest that you do not understand some of the basics. This may help.

https://cookfb.files.wordpress.com/2016/09/dual-battery-slides-2016.pdf

There are additional guides to system design and lead acid battery charging on the same page.

To your points:

-- Basic is good. The biggest advantage of an intelligent relay (aka voltage sensing relay) is that it automatically combines the batteries, especially when the charge is on the camper battery. An ignition controlled relay will only combine when the ignition is on. (Scholars debate the importance of this, but it is most useful for rigs that may stay parked for months between trips. E.g., a rig stashed overseas.)

-- No relay "manages" the charge process, that is done by your alternator/voltage regulator/vehicle computer.

-- Battery to Battery chargers, aka DC-DC or B2B, are generally used to boost the voltage to the camper battery when the vehicle's charging voltage is too low. Grossly, they do this by giving up some amps to gain more voltage.

-- Solar chargers require light, but they have the advantage of charging all the time there is light and many offer a more exact profile for your battery.

-- Shore chargers require shore power (duh!) but may offer a better profile and more amps. An inverter/charger is one way to achieve a kind of two for one.

Hope this is helpful.

 

[Bayou Boy]

Sounds like the OP found his Solution. I gained some insights from the Responses, yet, I’m still a bit confused on my Most Cost Effective, SAFE options for my (Jeep) Build. Simple solenoids are too .... Basic. VSRs (Voltage Sensitive Relays) don’t ‘manage’ the charging of two different battery types on one vehicle (I think). DC-DC Chargers ..... ? Smart Battery Mgmt .... pushing extreme limits of Budget.

Vehicle ~ ‘96 Jeep Cherokee XJ
Charging ~ Dodge 130A Alternator (?)
Batteries ~ BCI 51R AGM for “Cranking” BCI 34 Deep Cycle AGM for “House”
Battery Maintenance ~ Alternator when driving, (Possibly) Solar for Off-grid, AC “shore” power on INFREQUENT occasions.

Thoughts ? Blue Sea mentioned ? A CTEK option ? $400+ is simply out of a homeless person’s Budget ....

Both of those AGMs will need the same charging voltage. An ACR is fine for your setup.

 

[FlipperFla]

Blue Sea Systems make great products. Before I retired I did marine electronic/electrical installs. Never had anything by Blue Seas fail. One product I really like is their battery post fuse mounts. The 10A charge on the AC side might take overnight to bring up two large AGMs. I just have the ACR with a marine Xantrex 20A dual bank charger so each battery will get a 10A charge when on shore power and a 175W solar panel that gives me about 9.5A charge that I can A/B or charge both while camping. You cant go wrong with Blue Seas.

 

[Rico24/7]

Appreciate the Responses to (my) Query. Read through link provided by DiploStrat, thanks. OutbackJoe, as referenced also has some great info. I like that (he) doesn’t “push” products.
With the BlueSea product(s), I must be missing something, other than people’s allegiance. They seem to do Less, for Considerably More $$s than say, a Wirthco 20092 ..... ? https://www.wirthco.com/battery-doctor/battery-isolators-testers-monitors/battery-isolator-series

 

[DiploStrat]

What you may be missing: ampacity and, perhaps, reliability.

The bigger Blue Sea units can hold 500A. This may or may not matter for your rig. The Wirthco product may be excellent and your system may only need a smaller relay.

Many of us use various Blue Sea products because the failure rate is very, very low. Sadly, this is not always the case with some others.

 

[Rico24/7]

Appreciated ...... and Noted.

 

[James86004]

Many of us use various Blue Sea products because the failure rate is very, very low. Sadly, this is not always the case with some others.

That is exactly why we used a Blue Sea ACR 7610 in our Range Rover when we drove to Central America. The last thing we wanted was problems in Guatemala. Even though it is mounted under the hood, it still works perfectly 4 years later. We have forded quite a few deep creeks since then, too. We rely heavily on our dual battery system and our Engel fridge, and they have been awesome.

The alternator in the vehicle is 95 amps, so I felt we could use the much less expensive 7610. We also installed Blue Sea USB ports which still work perfectly. Our daughter likes bragging to her classmates we have a fridge and 8 USB ports in our 26-year-old vehicle.

I will add all the decisions we made were in consultation with this subforum, the folks here are great.

 

[DiploStrat]

Appreciated ...... and Noted.

To avoid being too much of a Blue Sea phanboi, you may find this article interesting; http://www.smartgauge.co.uk/choosesb2.html

With the car stereo wars, there are lots of relays out there and some may be great, but there is a reason that some of us are conservative curmudgeons.