ACR Wiring Question

[darleyhavidson]

Going to install a Blue Sea Systems 7650 ACR in the 2002 620VS. In the install directions it has a wire that goes from the start isolation terminal on the ACR to the start key switch. It has to be installed on the wire on the start switch that is only positive during cranking.

http://assets.bluesea.com/files/reso.../990310020.pdf

Question:
Which wire do I need to connect to in the start switch of a 2002 Ranger 620VS?

For those who have wired in an ACR, what other things do I need to keep in mind?

Any pictures you have would be helpful.

dh

[Marshfly]

That wire is optional and I have never hooked it up anytime I have installed that ACR. In reality, your batteries will rarely(never) be over the voltage necessary to engage the ACR while starting the engine anyway so they will be disconnected during start regardless.

Also, to make the most of that setup, you should also install the Blue Sea Dual Circuit Plus battery switch which will allow you to combine both banks for emergency starting as well.

[darleyhavidson]

That wire is optional and I have never hooked it up anytime I have installed that ACR. In reality, your batteries will rarely(never) be over the voltage necessary to engage the ACR while starting the engine anyway so they will be disconnected during start regardless.

Also, to make the most of that setup, you should also install the Blue Sea Dual Circuit Plus battery switch which will allow you to combine both banks for emergency starting as well.

The more I read on forums, the more confusion exists on the best way to install the ACR. You are correct, the more I read I do see that not everyone installs the starter isolation switch.

The 7650 is a kit that comes with the ACR and the battery switch you alluded to.

Thanks for the reply.

dh

[darleyhavidson]

I plan on placing the switch on the load side. What size fuses did you use and where in the circuit did you place them?

dh

[Lou r Pitcher]

A ghost charge can remain present on a cranking battery. The 120A SI ACR is not designed (or safe) to be able to carry starting currents. And neither are the wiring sizes specified as their intent is only for charging current and powering small boat accessories and lighting.

Why not hook up the start protection wire as designed by the manufacturer. [deleted optional reference]

[Marshfly]

It is literally called the “Optional Start Isolation Wire” on the wiring diagram. But what does the manufacturer know?

[Lou r Pitcher]

Wire is indicated as 'optional but is very necessary to provide the features included in the product's design and marketing. It is a fire safety risk to not wire ACR as shown.

[darleyhavidson]

Ok. Any feedback on inline fuses to use between the batteries and ACR or the batteries and switch?

[Marshfly]

Wire is indicated as 'optional but is very necessary to provide the features included in the product's design and marketing. It is a fire safety risk to not wire ACR as shown.

It would not be labeled as optional if it were a fire risk. The feature they are talking about is the words "start isolation" on the packaging. But we'll agree to disagree.

About the fusing. If it is all installed with batteries sitting next to each other, no fuse is needed. If your batteries are in different compartments, run on of these on each end of the cable at the battery. It sits on the terminal so is extremely compact. Size according to the chart on the link you posted.

https://www.bluesea.com/products/cat..._Battery_Fuses

[darleyhavidson]

It would not be labeled as optional if it were a fire risk. The feature they are talking about is the words "start isolation" on the packaging. But we'll agree to disagree.

About the fusing. If it is all installed with batteries sitting next to each other, no fuse is needed. If your batteries are in different compartments, run on of these on each end of the cable at the battery. It sits on the terminal so is extremely compact. Size according to the chart on the link you posted.

https://www.bluesea.com/products/cat..._Battery_Fuses

Perfect. The switch and ACR will be next to the batteries. Thanks for the assistance.

dh

[darleyhavidson]

When installing the switch and ACR combo, should I put the kicker on the House Battery or the Starting battery?

[Marshfly]

House is for house loads only. Put that dude on the starter.

[marlinpruett]

When I installed mine I ran the start isolation wire to my Mercury motor and hooked it into the starter wiring. Sorry I don't remember wire color but it's the same wire that runs to the switch. Was a shorter and easier wire run for me. I just ran up into the rigging tube into the motor.
As to fuses, I bought the recommended fuses by Blue Seas instructions. I mounted the whole setup on a board next to my batteries.

[darleyhavidson]

House is for house loads only. Put that dude on the starter.

The Blue Sea Systems Support technician indicated he connected his kicker to the House Battery on his personal boat. This was to ensure there is enough juice to start the big motor if using kicker motor all day. Figured I'd see what everyone else is doing.

[darleyhavidson]

When I installed mine I ran the start isolation wire to my Mercury motor and hooked it into the starter wiring. Sorry I don't remember wire color but it's the same wire that runs to the switch. Was a shorter and easier wire run for me. I just ran up into the rigging tube into the motor.
As to fuses, I bought the recommended fuses by Blue Seas instructions. I mounted the whole setup on a board next to my batteries.

Thanks for the info. That is a nice, clean install. Thanks again for sharing.

[Marshfly]

The Blue Sea Systems Support technician indicated he connected his kicker to the House Battery on his personal boat. This was to ensure there is enough juice to start the big motor if using kicker motor all day. Figured I'd see what everyone else is doing.

An engine should have enough charging current to replace what is lost while it is running. Even a kicker. If you run an engine to the house it is no longer a house battery but a second starting battery and you lose the entire point of a backup house battery.

[darleyhavidson]

[moetorola]

What is the advantage of this vs. say using something like this...????

It seems to me the minnkota style is better in the fact it will only will start charging the house battery (in this instance) only when the starting battery is charged. The SI-ACR is just a really connecting the starting and accessories battery in parallel, really no intelligence to it (am I correct?).

What if the house battery is drained slightly but not enough to go into lockout on the ACR. Once the relay is engaged with big motor running, the starting battery is dumping current plus the engine alternator to this house battery. I just don't see the advantage, and it appears the Minnkota MK1DC is about the same cost if not cheaper.

The Minnkota is current limited it appears.

https://minnkotamotors.johnsonoutdoo...Alternator.pdf

[Marshfly]

The largest benefit that I see is that an ACR will supply substantially more charging amperage than that Minn Kota thing. The Minn Kota only connects to your batteries with 16AWG cables so it can't be putting out more than 5 amps or so. You can get significantly more than that through an ACR. Your concerns about an ACR being "dumb" are exactly the reasons they work so well.

Actual 12v chargers waste a lot of amperage getting the voltage "right." Unless you have some weird battery that doesn't charge well on normal alternator voltage you are better off with an ACR.

[Lou r Pitcher]

Moetorola,

Yes.

Observing returned failed batteries after their cases have been removed sometimes shows us an obvious reason for their failure.......internal warped, distorted internal metal components caused by excessive high amperage flows (heat) in the battery. A jump switch or ACR may have been used in the circuit.

Jumping a dead battery with alligator style jumper cables though seems to get by fine........when measured for peak flows the rather poorly made contact points on the battery terminals limit and help prevent the highest currents from the charged battery to the dead battery. The jumper cables often need to be in place for a few minutes to transfer enough power into a fully discharged cranking battery to permit productive starting of an engine.

High amp capable jump/combine switches and ACRs simply bridging the batteries as if one though do not offer much of any limiting to excessive currents other than the minimum internal resistances of the dead battery and the donor battery. Especially in the case of AGMs and lithiums with very low internal impedance, a dead battery can appear much like a dead short across the fully charged high amp capable battery. An AGM can output a short circuit current of over 2500 amps.