Yamaha Crank/House battery charging with supplied harness or VSR/ACR

[whistler12]

Hi,

I have a new boat boat with twin engine Yamaha F200 (2021). Each engine has a crank battery and then there's a house battery to run the electronics on boat, fridge, livewell etc. It is currently wired so each engine charges it's respective crank battery and only the starboard engine is set up with a VSR/ACR to charge the house battery which is a larger AH to the crank battery. I believe there's a better way to wire up the system.

Is it more advantageous to purchase the additional yamaha wiring harness that I believe will connect to these engines for the purpose to charge the house, is this better than using a VSR/ACR? Could someone explain to me how the charging system works on an F200 with regards to charging the crank and then house battery.

I assume it also makes sense to use the charging capabilities of both engines to charge the larger house battery than just the one engine?

Any advice is greatly appreciated.

[fairdeal]

I assume it also makes sense to use the charging capabilities of both engines to charge the larger house battery than just the one engine?

Certainly it makes sense to offer the output from both engines to the house battery;
other than the initial expense to arrange it,
there is no downside.

The Aux output of the I4 F200 is different from most Yamaha models,
it actually functions similar to a non-Yamaha VSR,
connecting or disconnecting the output to the house battery
based on the voltage that the cranking battery is receiving.

So whichever you choose makes no functional difference;
it may be easier to install the ACR, than thread the Yamaha cable through a rigging tube,
the ACR may be a bit less to purchase,
you may feel a benefit - even if only aesthetically -
of having matching connections for both engines.

[boscoe99]

Is there a concern that you might not have adequate electrical power to keep your house battery fully charged?

[whistler12]

Certainly it makes sense to offer the output from both engines to the house battery;
other than the initial expense to arrange it,
there is no downside.

The Aux output of the I4 F200 is different from most Yamaha models,
it actually functions similar to a non-Yamaha VSR,
connecting or disconnecting the output to the house battery
based on the voltage that the cranking battery is receiving.

So whichever you choose makes no functional difference;
it may be easier to install the ACR, than thread the Yamaha cable through a rigging tube,
the ACR may be a bit less to purchase,
you may feel a benefit - even if only aesthetically -
of having matching connections for both engines.

thanks for your response, is that wiring diagram specifically for this particular I4 F200 yamaha? If so it appears it does not parallel the batteries, a VSR or ACR will parallel batteries.

My concern is parallel charging of dissimilar batteries and the potential issues with that and relay cycling.

based on the diagram you've provided the yamaha cable would be a better option. Any idea on how much these cost?

thanks,
tom

[whistler12]

Is there a concern that you might not have adequate electrical power to keep your house battery fully charged?

My concern is that if we have all electronics on at once, when the VSR switches over to charge the house battery because of the significant load the voltage will drop and the VSR/ACR will disengage.

My other concern is I've heard parallel charging batteries of different size is not ideal. they will only differ in amp hours, which i know is not as bad as different types of batteries but I have heard is not ideal.

[Keithbaja]

U want to use cranking or dual purpose batts of the same size and manufacturer. I'm sea this issue all the time. Also in RVs. Some very newest high horse o/b can have regulator set for deep cycle batts. Read your owners manual....... And Don't use a Zener diode battery isololater with pwr in and two outs for battery's. U lose 1VDC across the diode and your batts never get correctly charged. I highly recommend "BLUE SEA SYSTEM" ACR. Batterys, Fish, Women are loved by men. But SOO misunderstood......

[fairdeal]

My concern is that if we have all electronics on at once, when the VSR switches over to charge the house battery because of the significant load the voltage will drop and the VSR/ACR will disengage.

Well, the Blue Sea ACR once connected,
will not disconnect until both batteries are >12.75 and stay that way for 30 seconds.
Since the engine is running and providing power,
that does not usually occur -
although I have heard of it happening with a large house,
when the engine is at idle and alternator output at its lowest.
all the more reason to have ACRs on both engines,
to double the amps available.

As for concerns about 'parallel charging' -
if you have more than one battery,
(unless they are connected in series ie. two 6 volt batteries)
they are going to be charging in parallel.

It makes no difference to either battery,
whether or not they are the same "type"
or "size" or manufacturer.


Perhaps Boscoe will chime in to elaborate.
Besides being by far the most knowledgeable person here in matters Yamaha,
few people on the internet have as much actual expertise
in the real world behavior of alternators and batteries

[Keithbaja]

Well, as a fuel injection and electrical spe******t with over 40 years in the biz that designs, repair and upgrades electrical systems on patrol vessels (SAR) boats, yachts, motor homes, off grid systems. I at 95 a hr I sure in hell better know what the hell I'm doing. You do NOT want to miss match battery's for a host of reasons. ain't up for debate !!!

[fairdeal]

...with over 40 years in the biz that designs, repair and upgrades electrical systems...I sure in hell better know what the hell I'm doing.

Please then, help me understand;

here's a simple example -

why exactly, would this be a problem?

[boscoe99]

U want to use cranking or dual purpose batts of the same size and manufacturer. I'm sea this issue all the time. Also in RVs. Some very newest high horse o/b can have regulator set for deep cycle batts. Read your owners manual....... And Don't use a Zener diode battery isololater with pwr in and two outs for battery's. U lose 1VDC across the diode and your batts never get correctly charged. I highly recommend "BLUE SEA SYSTEM" ACR. Batterys, Fish, Women are loved by men. But SOO misunderstood......

In a system that parallels two or more batteries only while they are being charged (current flowing from the motor to the batteries), how does the electrical generation system know that the batteries are not of the same type, the same size, the same age or from the same manufacturer? What might the electrical generations system do differently?

[boscoe99]

To maximize use of the current that is available from twin F200 isolator leads to one house battery, here is a Yamaha suggestion.

[boscoe99]

My concern is that if we have all electronics on at once, when the VSR switches over to charge the house battery because of the significant load the voltage will drop and the VSR/ACR will disengage.

It is not abnormal for a VSR/ACR to cycle on and off. Engage and disengage. I would go so far as to say that is is normal. Because that is the way that it is designed to work.

The VSR/ACR is normally open. No current can flow from the starting battery side to the house battery side.

The motor is started. The electrical generation system starts to output electrical power. Power to the starting battery only.

When the VSR/ACR senses a voltage greater than X at the starting battery side the VSR/ACR will close and allow current to flow to the house battery. If the electrical system is powerful enough to provide current to both the starting battery and the house battery while maintaining X voltage, the VSR/ACR will remain closed/on/engaged. Both batteries will be receiving whatever current they will.

Now if the electrical system is not powerful enough to provide current to both batteries while maintaining X voltage, the VSR/ACR will open/disengage. Because the starting battery always takes priority. Once the voltage comes back up above X on the starting battery side of the VSR/ACR, the VSR/ACR will close/engage. Again providing current to both batteries.

If the electrical loads on the house battery are so great that the motor cannot keep up with those loads, then the VSR/ACR may continually open and close/disengage and engage. No harm no foul.

[whistler12]

It is not abnormal for a VSR/ACR to cycle on and off. Engage and disengage. I would go so far as to say that is is normal. Because that is the way that it is designed to work.

The VSR/ACR is normally open. No current can flow from the starting battery side to the house battery side.

The motor is started. The electrical generation system starts to output electrical power. Power to the starting battery only.

When the VSR/ACR senses a voltage greater than X at the starting battery side the VSR/ACR will close and allow current to flow to the house battery. If the electrical system is powerful enough to provide current to both the starting battery and the house battery while maintaining X voltage, the VSR/ACR will remain closed/on/engaged. Both batteries will be receiving whatever current they will.

Now if the electrical system is not powerful enough to provide current to both batteries while maintaining X voltage, the VSR/ACR will open/disengage. Because the starting battery always takes priority. Once the voltage comes back up above X on the starting battery side of the VSR/ACR, the VSR/ACR will close/engage. Again providing current to both batteries.

If the electrical loads on the house battery are so great that the motor cannot keep up with those loads, then the VSR/ACR may continually open and close/disengage and engage. No harm no foul.

Firstly, thanks all for the advice, I'm definitely learning a lot.

Could undervoltage lockout occur (below definition is taken from bluesea website)? I guess if the alternator output is good enough to stop this from happening then not an issue, although as it stands only 1 engine is charging the house battery, which could pose an issue for me

• What does “Undervoltage Lockout” mean?
  As a safety feature, some ACRs prevent combining into a severely discharged battery. A dual-sensing ACR will monitor the voltage on both batteries and will not connect if either battery is below the undervoltage lockout level. Use caution when combining into a battery with extremely low voltage, because this might represent a faulty battery or a problem elsewhere in the system.

[whistler12]

To maximize use of the current that is available from twin F200 isolator leads to one house battery, here is a Yamaha suggestion.

So does the 1 - 2 switches allow each engine to be started from either start battery? I guess adding an emergency parallel switch would improve this option further?

In my opinion this is a better setup than using VSR's. Would you agree?

[99yam40]

So does the 1 - 2 switches allow each engine to be started from either start battery? I guess adding an emergency parallel switch would improve this option further?

In my opinion this is a better setup than using VSR's. Would you agree?

Well I would think having a switch that you could select which battery you want to use is a good idea, but paralleling the batteries may not be a good idea.

Like the other post mentioned, what happens if a battery goes bad or a short happens when they are paralleled?
it will negatively affect the good battery if one goes bad.
or both batteries in the case of a short in wiring