Blue Sea Systems 7601 m-Series Automatic Charging Relay, 12/24V DC, 65 Amp

Have been using it to charge my trolling motor battery. After many months of use I am very satisfied. The connection is simple. Out of sight, out of mind.

I am using this to auto charge the secondary battery in a marine application. I added the secondary battery to provide independent power to all but the engine ignition, starter, and electric fuel pump. The alternator is also on the primary battery side. I originally used a manual 1-2-all switch, but when I would crank the engine, the voltage drop caused my electronics to reboot. I changed the switch to a Blue Sea Systems e-Series Dual Circuit Plus Battery Switch and added this switch to auto charge and isolate. Works very well. My crank battery always maintains enough power to start the big v8. After running lights and electronics all night off the secondary battery, the engine starts off the primary. After a few minutes of recharging the primary, this switch engages the secondary for charging as well and the lights all brighten. When in storage, I keep a 1.5amp auto charger on the secondary battery, since I often run lights and radio while working on the boat. Have noticed this switch will engage the primary battery and keep it charges as well, given enough time. This works even with the battery switch turn off, using the wiring recommendations from Blue Sea. Great solution to a dual battery isolation issue. No more forgetting to disengage the primary battery and waking to a no start situation. I used the Blue Sea Systems 285-Series Surface Mount 50A Circuit Breaker to protect the secondary circuit.

It works good.I held off one star because it also needs a manual override. Once a battery discharges too much it will NEVER reconnect. They do make one that has this feature but it costs a lot more $$$. For most applications, this will work well just keep this in mind that you may want a manual switch in line also.

Installed as a acr between on engine battery and the house battery. No problems with the installation but needed rt angle (flag) 0.25 " terminals for the GND and SI connections otherwise the cover interferes that I did not anticipate. They should have been supplied or noted.

Bought this for my Yamaha Rhino side-by-side. I needed to add another battery that could handle my winch use, especially during the winter. Most offroad smart relays like this are almost double the price. Blue Sea makes great products for the marine world that see more water than *most* offroad users, so it only makes sense to use them for offroad vehicles.This is easy to install and wire up. Instructions are pretty straight forward. I have dual voltmeters, one for each battery and you can see where after the primary starter battery reaches a charge and and the relay kicks on, that the second battery instantly climbs. It works perfectly. I'd recommend this for just about any use where you need two batteries.

Bought it for my boat and it works great

I bought this, hooked it up, and no lights. I went through tech support, and metered everything out. They say it’s working, but with no status lights, I can’t tell if there the batteries are combined, charging, or dead.Blue Sea knows this is an issue but seems unwilling to do anything about.Beyond return window, so tossing it and getting a replacement at a third the cost of this.

I have been storing my boat where it is difficult to charge the trolling motor battery without removing it, and was looking for a way to charge it while underway. I installed the Blue Sea relay and it has been a life saver. Running the main engine keeps the trolling motor battery sufficiently charged to fish like I want to. On the last trip the battery was running low, so I just ran the boat at a bit above idle for about 10 minutes and was good to troll again.I did install a cut-off switch that removes the ground wire (and disables the device) so it doesn't drain the batteries when in storage for a long time.The biggest challenge for the install was finding the right gauge wire and connectors to run between the batteries and the switch.