Victron Battery Monitor problem

[DanM]

Friends,

I've recently installed a Victron Battery Monitor in my Catalina 30 and it's working well but it is failing to keep any data on:

1. Depth of Last Discharge
2. Depth of Average Discharge
3. Number of Charge Cycles

After much effort and finally just a blast mail to every salesman listed worldwide on the Victron site I finally got a response telling me that it would seem that the Monitor is not recognizing a fully charged state and to check a few settings. I check those settings (tail current, charge detection time and charge voltage) and all seems well there.

The documentation says that it will automatically sync itself when the batteries reach a fully charged state and it does report that it has sync'd itself four times since I've installed it.

I'm wondering if I need to manually sync it, or perhaps remove power from it altogether and sort of "re-boot" it, if that makes any sense.

BTW, the Peukert Exponent for Sam's Club 6 volt lead acid golf cart batteries made by Interstate is 1.07 and inputting that info to the monitor made it much more accurate in the state of charge field.

Thanks! Dan.

 

[Stu Jackson]

You should also read this: http://c34.org/bbs/index.php/topic,4922.0.html

 

[DanM]

Thanks Stu, I need to spend some time on the C34 site given how similiar many of the C30 issues are.

In the case of my Victron monitor though it doesn't look like I'd be subject to the "gotcha".

I did find a five page monitor thread and posted my question there, sorry to start another thread here, I should have done a more thorough search first.

Take care, DanM.

 

[Stu Jackson]

It's not the monitor, it's the defaults in the algorithms. As I mentioned in the Roger's thread, it's how YOUR boat is set up that will determine what you may (not always) need to change.

 

[Maine Sail]

Guys,

Depending on the monitor to always self reset will cause lots of frustration especially when you get into small solar panels & such. The most simple and accurate way I know of keeping them calibrated is to do a manual re-set when your charge acceptance current is less than 1.5% - 2% of the banks 20 hour Ah rating. I manually re-cal once per week even if it has self re-set. I also set my monotor to automatically re-set at 1% of bank acceptance as opposed to the standard default of 2%..

So when a 200 Ah bank is only taking 4 amps of charge current you can, for all intents and purposes, effectively consider it full and re-set. They will eventually take less than 1% but this takes time so anywhere below 2% is a safe re-set zone. Remember this is 2% acceptance with no loads turned on. I prefer 1% but 2% is "industry" full...

You can also get your own baseline for "full" by watching your known full bank with the alt running and NO loads on. Once you get close to that type of accepted current consider that your re-cal current..

 

[DanM]

Thanks R.C., I did just manually sync my Victron BMV-600s although I'm typically on a Xantrex 20a charger in my slip and the monitor seems to be doing a great job of monitoring so far, syncing itself as advertised an all.

Would you have any idea why I'm not getting any info in the history menu for average depth of discharge? It is showing tracking that it is syncing itself and showing 100% SOC, I'm just stumped on why I can't get the average depth of discharge in the history menu. I'm leaning toward thinking there might be a problem with the unit.

Also, it would appear that Victron doesn't have any kind of tech support number either which is a real downside for me for owning their monitor. I guess that's one of the reasons I don't cringe (too much!) when I pay Blue Sea Systems prices because I know I can pick up the phone and get an answer.

 

[Maine Sail]

Thanks R.C., I did just manually sync my Victron BMV-600s although I'm typically on a Xantrex 20a charger in my slip and the monitor seems to be doing a great job of monitoring so far, syncing itself as advertised an all.

Would you have any idea why I'm not getting any info in the history menu for average depth of discharge? It is showing tracking that it is syncing itself and showing 100% SOC, I'm just stumped on why I can't get the average depth of discharge in the history menu. I'm leaning toward thinking there might be a problem with the unit.

Also, it would appear that Victron doesn't have any kind of tech support number either which is a real downside for me for owning their monitor. I guess that's one of the reasons I don't cringe (too much!) when I pay Blue Sea Systems prices because I know I can pick up the phone and get an answer.

Did you talk to Chris R. in Maine (207 ) 354-0493 ? That History Mode is a feature I have never used nor really care about much. Do keep in mind that the SAME button used to access the "H" features is the button used to clear/reset the "H" features. Holding that button for just 5 seconds clears all your history.

The most important screen is your SOC/Sate of Charge screen not your CE screen as the SOC screen calculates for Peukert effect and CE/Consumed Energy/Consumed Ah's does not.


Also think about what you paid for the Victron vs. a similar system with Blue Sea or Xantrex.

 

[DanM]

I emailed Chris and never got a response, I'll try calling him. Thank you for the number.

The monitor is a great value for sure though, I just have a hard time mentally with installing something and then not having it do what the book says it should do.

Agreed though that the history features I'm trying to make work are just sort of trivia anyway, the SOC feature works great!

Thanks for your time!

DanM.

 

[DanM]

Just to put an end to this thread I'll answer myself!

I got a resonse from Johannes from the Victron Energy office in The Netherlands and he was able to help me get to the bottom of the monitors history menu which is not documented in the owners manual.

I'll just list the fields that were reporting odd data, some of the fields are self explanatory.

H2: The depth of the last discharge. This field will be reset to zero each time the monitor determines the battery is at 100% SOC.

H3: The depth of the average discharge. This field will only average discharges that take the battery below 65% SOC and then return to more than 90% SOC. I was getting a zero in this field because I had not taken my house bank below 65% since installing the monitor.

H4: The number of charge cycles. The monitor measures a cycle as a discharge below 65% SOC and then a recharge to at least 90% SOC.

As far as set up goes, I only had to make changes to the size of my battery bank in ah and the Peukert Exponent of my batteries to get it to produce a very accurate state of charge. Nice little gizmo!

DanM.

 

[IanJ]

I installed one of these recently, but am still not sure if it is calibrated correctly. Anyone have anything on how to do this apart from the postage stamp sized manual?

 

[Roger Long]

Just to put an end to this thread..

Excellent info. I'll print it out and fold it up in the manual, if I can get the print small enough and cut the paper small enough to fit Thanks for tracking it down.

Too good a thread to end so I'll ask a question to keep it going. Does anyone know if the red wire just called "12 V. supply" is simply power supply or does it sense voltage and therefore needs to be on the battery terminal for greatest accuracy. My monitor is right next to my battery switch and it would be nice to just attach the wire there and not have a small wire running all the way back and into my battery box.

Seems like there would be less voltage drop in the big, fat battery cable than in the small wire but maybe it's calibrated for the known drop in the wire they supply.

 

[Maine Sail]

Just to put an end to this thread I'll answer myself!



DanM.

Thanks Dan. Great info!

 

[Maine Sail]

Excellent info. I'll print it out and fold it up in the manual, if I can get the print small enough and cut the paper small enough to fit Thanks for tracking it down.

Too good a thread to end so I'll ask a question to keep it going. Does anyone know if the red wire just called "12 V. supply" is simply power supply or does it sense voltage and therefore needs to be on the battery terminal for greatest accuracy. My monitor is right next to my battery switch and it would be nice to just attach the wire there and not have a small wire running all the way back and into my battery box.

Seems like there would be less voltage drop in the big, fat battery cable than in the small wire but maybe it's calibrated for the known drop in the wire they supply.

You are best to connect it to the battery terminal as any resistance when that cable is under load would give a different reading at the long end vs. the battery post.

 

[Roger Long]

You are best to connect it to the battery terminal as any resistance when that cable is under load would give a different reading at the long end vs. the battery post.

That little red wire has got to have more resistance than my huge battery cable. What if I were to measure the resistance of my battery cable and the Victron wire? Could I then proportion the length of the Victron wire so that it would give me the same voltage drop when coiled up and connected to the switch end of the battery cable right next to the display unit?

Or, is the behavior of the wire under load more complex than that? It would be nice not to have that little wire snaking all the way back to the battery box.

 

[Maine Sail]

That little red wire has got to have more resistance than my huge battery cable. What if I were to measure the resistance of my battery cable and the Victron wire? Could I then proportion the length of the Victron wire so that it would give me the same voltage drop when coiled up and connected to the switch end of the battery cable right next to the display unit?

Or, is the behavior of the wire under load more complex than that? It would be nice not to have that little wire snaking all the way back to the battery box.

But there is virtually no current running through that little wire thus no voltage drop as all it is doing is powering the meter, milliamps, and measuring voltage of the battery terminal. The main battery cable could be seeing VD at the switch end depending upon condition & loads and you'd then be measuring that. Can it work, sure, is it the ideal connection point, no but there are worse thing you could do...

 

[Roger Long]

Oh, I get it. Big flow through big wire can result in more voltage drop, even upstream of the loads, than micro load through very small wire. I was thinking that the voltage drop in the battery wire would be strictly a function of its resistance.

This is a lot like the difference between static and indeterminate analysis of structural loads. In the first, you assume that everything is perfectly rigid and just look at the geometry. In the later, you consider how everything flexes and compute the stresses after it's all settled into its new shape.

 

[Maine Sail]

Oh, I get it. Big flow through big wire can result in more voltage drop, even upstream of the loads, than micro load through very small wire. I was thinking that the voltage drop in the battery wire would be strictly a function of its resistance.

This is a lot like the difference between static and indeterminate analysis of structural loads. In the first, you assume that everything is perfectly rigid and just look at the geometry. In the later, you consider how everything flexes and compute the stresses after it's all settled into its new shape.

Big flow, plus two or more connections, plus any corrosion can create some drop and you'd then be measuring that drop. You'll likely be fine but having switched boats from 2GA wire to 1/0 or 2/0 and then having them ask if I had installed a new starter, well.... VD happens even on big wire..

 

[Roger Long]

Is there any problem with induction in a sensing wire like that? The neat installation solution for my situation would be to take the wire across to the battery switch and then cable tie it to the battery cable back to the terminal.