Blue Sea Systems Add-A-batterijkit

No deficiencies observed after several months in service charging large batteries on a boat.

Works great easy to install

After much reading and actually calling and talking to Blue Sea's tech support I'm very impressed with this product and their support. I know others have worried about the small voltage drain from the ACR unit. The ACR unit uses a small amount of current and over a VERY long time and it can drain the batteries it’s monitoring. I talked to the Blue Sea's Tech about this, and they had estimated about 4 months of just sitting there monitoring the battery voltage before the voltage drop would start to cause problems starting the engine. (This would depend of course on the condition of the battery and size/rating of it). However, when talking to the tech about this, there are a few things you can do to completely turn off the ACR. First if you hook it up like they show in the product picture you will need to hook up a small toggle switch to one of the three spade connectors on the unit to turn it off. Or if you are like me and want to KNOW everything is turned off when you put your boat away, you can wire as I have diagramed in the picture attached. By putting the ACR on the "downstream" side of the switch, you can turn everything off when you turn off the main switch. This will still allow the ACR to monitor the batteries when you have the boat in use and will function normally. The only thing would be if you put a charger on one of the batteries when in storage, you would want to leave the master switch to the “on” position so the ACR could function and allow current from one battery to the other. Otherwise, if you had the master switch in the off position you would only be charging the one battery that the charger is hooked up to. The batteries would be isolated from each other and from the ACR.Also, when I was speaking to the tech I mentioned I was I was worried about the 120 amp rating of the unit when the ACR engages. If there is a big voltage differential between the two batteries, there would be a surge of current across the ACR when it connects the two batteries. This 120 Amp is a continuous rating and the ACR will not engage the circuit if there is too big of voltage difference. This would be a case where one battery is bad, has a bad cell or has an extremely high load on it and cannot maintain a high enough voltage. The ACR will disengage and will try to isolate the batteries in that case. In continuous operation the ACR would really only see the total amount of output that the alternator could generate. In my case this is about 100 amps so the 120 amp ACR unit is sufficient.For the product itself, it is very solidly made, and has been working flawless. I had a Pergo basic 1, 2, 1+2, Off switch in my boat, and got tired of trying to remember to flip the switch to 1 when anchored out, then back to 1+2 when cruising around. With this no need for any of that. Just turn the main switch on when I’m getting all the stuff loaded in, and off when we put it in storage. SIMPLE SIMPLE SIMPLE.

great product, quick delivery

Blue sea electrical equipment is always well made. This is no exception