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Winter

Alternator Controller behaviour

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Agreed, except can't say 14.1V is ideal Vset.

Curve heading for taper current all looks good.

Is that graph from your Victron 702 bluetooth to phone?

Like it! IMO, another level or two up from Balmar SG200. :-(

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Lateral I like your idea of an on off switch on the regulator supply, might try that. 

The graph is from a Victron 712, cabled into a Victron Venus GX which uploads data to the cloud, graphs are then from the Victron VRM portal

See here https://vrm.victronenergy.com/installation/36577/advanced (not my boat)

 

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6 minutes ago, Winter said:

Lateral I like your idea of an on off switch on the regulator supply, might try that. 

The graph is from a Victron 712, cabled into a Victron Venus GX which uploads data to the cloud, graphs are then from the Victron VRM portal

See here https://vrm.victronenergy.com/installation/36577/advanced (not my boat)

 

Winter : I have the VRM portal as well (except I did it with a Rasp Pi) - its bloody brilliant isn't it?

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1 hour ago, bigal.nz said:

Winter : I have the VRM portal as well (except I did it with a Rasp Pi) - its bloody brilliant isn't it?

It is bloody brilliant, and Victrons willingness to open that up to rasp pi tinkerers is fantastic. the bmv 712 plus a rasp pi cant be beaten. 

puts Victron at the top of my list. their stuff is pretty good value!

 

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Two points among all the conversation. The 14.1V is a tad low. i would suggest 14.4V. All this will achieve is getting a tad more current going in. But 14.1V  is not a problem as such.
The slight differences in Voltages as it cuts in and out is probably an efficiency thing due to Heat. As the Charge load decreases, the ALT would cool somewhat and the heat can make a dramatic difference to it's efficiency. So as it gets a tad cooler each cycle, it is able to increase the output voltage a tad. The increase is not huge and I would not worry one little bit about it.

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On 5/04/2020 at 5:31 PM, wheels said:

Two points among all the conversation. The 14.1V is a tad low. i would suggest 14.4V. All this will achieve is getting a tad more current going in. But 14.1V  is not a problem as such.
The slight differences in Voltages as it cuts in and out is probably an efficiency thing due to Heat. As the Charge load decreases, the ALT would cool somewhat and the heat can make a dramatic difference to it's efficiency. So as it gets a tad cooler each cycle, it is able to increase the output voltage a tad. The increase is not huge and I would not worry one little bit about it.

What I have noticed  when charging from <80%soc,  is that what is supposed to be constant voltage (absorbtion phase) is not exactly.

It slowly build to from 14.5x to  Vset (max setting of regulator) and reaches it at~ 0.01C.

Similar to a line drawn through the tops of Winters V peaks. But +0.4v

My endurants are above 12.8 after 48hr of no load IF I get to specified  taper current.

If not, they are less. ( Not charged to 100%) Meaning, that I suspect voltage won't stop

increasing until emf's are balanced, or you cook your batteries.:wacko:

You relate this to efficiency as opposed balancing surface charge EMF's Wheels?

Whatever, I guess, the trend is there with mine. Thats what counts.

0.01C is such a PIA to get to. Hence you are predisposed to battery homicide.

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On 5/04/2020 at 5:31 PM, wheels said:

Two points among all the conversation. The 14.1V is a tad low. i would suggest 14.4V. All this will achieve is getting a tad more current going in. But 14.1V  is not a problem as such.
The slight differences in Voltages as it cuts in and out is probably an efficiency thing due to Heat. As the Charge load decreases, the ALT would cool somewhat and the heat can make a dramatic difference to it's efficiency. So as it gets a tad cooler each cycle, it is able to increase the output voltage a tad. The increase is not huge and I would not worry one little bit about it.

I've been meaning to comment on this for a few days. Its not often Wheels and I disagree on technical stuff, but in this case the voltage  of 14.1 is not a minor issue IMO. 

That voltage, rather than 14.4 -14.7 (whatever the PDS says for your specific batteries) will make an enormous difference to the time taken to charge the batts, and, in fact, they may NEVER get to 100% if not within the manufactures recommended voltages.

So, before replacing the reg, check the voltage sense connections and cables for correct connection and cable or terminal issues causing voltage drop. 

If the voltage cannot be corrected, change the regulator for one that can. Regs are still cheaper than new batts. 

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No disagreement IT. I thought I had made the same point about the 14.1 should be 14.4. I went back and re read my post and see I did not make that very clear at all and in fact messed up the comment completely. And I can't even use the excuse of posting in the early hrs of the morning either. I see it was 5.30PM. So I stuffed up there.
I don't know enough about what the Batteries are and the finer details of the Reg to personally say go to 14.7, but most certainly 14.4. is the essential Voltage point for the reg to be set to. If you go above 14.4, monitor the bank for a few charge cycles to ensure they are not over cooking. Or as IT said, if you can possibly get that information from the Battery manufacturer.

Question, does the Reg have Temperature monitoring of the Batteries ?? Temperature is very important. The ambient temperature between Summer and Winter can make an enormous difference with the current output that the Reg will make the ALT produce. I used to use the Ambient Temp setting when I wanted to push a higher charge current into the Bank and the Charge Voltage rose, so as the charge time was reduced. But that also means you have to monitor the Bank to ensure they are not getting hot and to watch the ALT that it is not being pushed too hard.  Ambient Temp will also make a huge difference in what the batteries will accept. So having an actual sensor can be a big advantage so as the Reg follows the Banks temp/ charge curve
 

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9 hours ago, lateral said:

You relate this to efficiency as opposed balancing surface charge EMF's Wheels?

 

Surface charge is not a thing in this instance. As a Plate charges, it starts from the surface and the charge works it's way in toward the center of the plate material. Surface charge is when the internals of the plate have no charge (a couple of reasons can cause this) and only the surface has a charge. The Battery can be voltage tested with a good reading of a charged battery. But the Battery actually has no Current available. So with a load placed on it, the Voltage will simply drop away.

The Efficiency part I was referring to is the Efficiency of the ALT itself in relation to the temperature of the ALT. If it is really hot, the resistance of the copper windings change and the magnetic field becomes weaker, thus the ALT will never deliver the Current that it would normally be capable of. Those time intervals where the ALT is not producing a current would be a cooling period on for those Windings. If you also note the graph, the initial leading current peak is higher than the end of the charge period and that could well be the heat rising causing that ALT charge efficiency dropping slightly. As the cycles continue, the peaks are ever so slightly higher ( I think, without going back to check)
There are other mechanical causes that can do this as well, so my comment is not something to take as fact without knowing a lot more about the installation.

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Ideally a reg that is completely voltage adjustable, and has temp sensors for the alt AND the batts, and hopefully a ramp up period to save on belt wear. Plus a hot rated alt. That's the ideal, but as you have discovered, its not inexpensive to do.

I had this on my old motor, although only with a 75amp balmar alt.

On the new D240, it comes with a 115 amp alt with temp sensing - it reduces output if to hot. However its a stupid reg, set voltage, although it has voltage sensing to allow for diodes etc.  I have added one of these http://nordkyndesign.com/product/nordkyn-electronics-vrc-200-charge-reference-controller/ it uses the standard alt voltage sense wire to control the alt, and makes it fully adjustable.

It keeps the temp sense for the alt as standard and has a battery temp sense option. Works great for anyone with a D2 series volvo...

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