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[booster]

Originally Posted by GallenH

Yes. Don't know how I managed to do that but I had to flip the shunt as my cables were carefully selected to avoid excess. But that worked fine. You know I always wondered why my amp consumption would read 2amps and not -2amps. Unfortunately had to resync the Victron since you're supposed to do that when it's been disconnected. So this reading of amps consumed and % is undoubtedly false. Looks like my battery voltage has dropped again.

Attachment 14886

Shunts get wired backwards a lot, I think. I have done a couple of times.


Where do you have the battery reference wires for the shunt connected on the none shunt ends?

[GallenH]

Not sure what you mean by battery reference wires. Before the shunt, the negative battery wire simply went to the loads (I'm assuming the chassis ground). The shunt was inserted into this circuit (battery -->shunt-->loads). The + wire from the shunt goes directly to the battery + terminal. I have the battery temp monitoring option but it's not set up.

[booster]

Originally Posted by GallenH

Not sure what you mean by battery reference wires. Before the shunt, the negative battery wire simply went to the loads (I'm assuming the chassis ground). The shunt was inserted into this circuit (battery -->shunt-->loads). The + wire from the shunt goes directly to the battery + terminal. I have the battery temp monitoring option but it's not set up.

That is the right place for it. How close to the battery is the shunt so the negative reference is seen.


Is the positive wire connected to the correct connection on the Victron terminal strip? It should be on the one that is closest to the cable connection to the head unit.

[GallenH]

Originally Posted by booster

That is the right place for it. How close to the battery is the shunt so the negative reference is seen.

The cable is about 3-4' going from the battery to the shunt. "battery cable" gauge.

Is the positive wire connected to the correct connection on the Victron terminal strip? It should be on the one that is closest to the cable connection to the head unit.

Yes. Positive wire from shunt in correct location on shunt.

This last reading (1+ hr. out) appears to show that the monitor is functioning.
Shows that I'm consuming amps, and the amound consumed reflects a 4% reduction (96%) in battery state of charge (100Ah battery). But it's obviously not at 96Ah since the voltage is now 12.04.

IMG_4036.jpg

[booster]

Originally Posted by GallenH

The cable is about 3-4' going from the battery to the shunt. "battery cable" gauge.



Yes. Positive wire from shunt in correct location on shunt.

This last reading (1+ hr. out) appears to show that the monitor is functioning.
Shows that I'm consuming amps, and the amound consumed reflects a 4% reduction (96%) in battery state of charge (100Ah battery). But it's obviously not at 96Ah since the voltage is now 12.04.

Attachment 14887

When a battery does that, as in looks to be fully charged based on off charge voltage, but drops voltage very quickly with much less ah use, it is typically an indication that the battery has lost it's capacity to hold charge.


You may be able to recover at least some of the capacity if you can provide a "conditioning" charge, which is similar to and equalization in a wet cell.



You put a high voltage of about 15.1v on a fully charged battery for a relatively long time. The tech manual explains it well.


It is worth a try, but you need to be able to supply that voltage and many chargers can't do. You also need to disconnect the van electronics or remove the battery from the van to protect them.


For right now, as long as the monitor is working now, I would turn on the shore charger to see if it will actually charge, as that hasn't been confirmed at this point. Once that is done, you can address the battery issue.

[GallenH]

Fantastic help! I can't tell you how much I appreciate your helping me with this and the speed at which you reply. Many many thanks. I can't believe that my monitor has been set up incorrectly for years. Rookie error.

I was just thinking that it would be good to connect the shore power and the charger/convertor. It should show now as incoming on the monitor. Might try running the engine after that to see what's coming from the alternator.

I don't have the capacity to try to do a reconditioning. LifeLine recommends that it should only be done by a true tech (obviously not me) and I don't have a charger with that capability anyways. The pic at the end is another reading an hour after the last. It shows proper consumption and overall amps drawn but the voltage has dropped even more.

Time, I think, for a new battery. I'm going to replace it with a lithium. I replaced the convertor/charging section of my old Magnetec with one from
Progressive Dynamics with the charge wizard about 5yrs ago. IIRC it has a switch or jumper on the back to set for lithium. I'm assuming that I need a DC-DC convertor for the line coming from the alternator. I'm thinking 40A since I have a 40A breaker on that line. Don't know if any spike coming from the DC-DC would trip breaker, though. I'm also assuming that I can replace the isolator with a bus bar since the DC-DC is one-way. Does that plan make sense to you? Any suggestions?

Very best,
Glenn

IMG_4037.jpg

[booster]

Originally Posted by GallenH

Fantastic help! I can't tell you how much I appreciate your helping me with this and the speed at which you reply. Many many thanks. I can't believe that my monitor has been set up incorrectly for years. Rookie error.

I was just thinking that it would be good to connect the shore power and the charger/convertor. It should show now as incoming on the monitor. Might try running the engine after that to see what's coming from the alternator.

I don't have the capacity to try to do a reconditioning. LifeLine recommends that it should only be done by a true tech (obviously not me) and I don't have a charger with that capability anyways. The pic at the end is another reading an hour after the last. It shows proper consumption and overall amps drawn but the voltage has dropped even more.

Time, I think, for a new battery. I'm going to replace it with a lithium. I replaced the convertor/charging section of my old Magnetec with one from
Progressive Dynamics with the charge wizard about 5yrs ago. IIRC it has a switch or jumper on the back to set for lithium. I'm assuming that I need a DC-DC convertor for the line coming from the alternator. I'm thinking 40A since I have a 40A breaker on that line. Don't know if any spike coming from the DC-DC would trip breaker, though. I'm also assuming that I can replace the isolator with a bus bar since the DC-DC is one-way. Does that plan make sense to you? Any suggestions?

Very best,
Glenn

Attachment 14892

Yeah, the PD should have a basic lithium program, probably with float. Although not ideal, it is probably like about 98% of the other chargers out there because of economics and the market place, especially for a small battery bank setup. The PD will also enable you to reactivate a BMS shut down battery as it is a power supply type charger that when it isn't on Wizard is just a fixed 13.6v supply.


Yes you would need a B to B charger to replace the isolator you have and some control of it with either the ignition run power or switches, I think.

[GallenH]

Booster, I forgot to ask. I know you converted from LifeLines to lithium. Been reading your updates, etc. Wanted to ask what brand Li.

[booster]

Originally Posted by GallenH

Booster, I forgot to ask. I know you converted from LifeLines to lithium. Been reading your updates, etc. Wanted to ask what brand Li.

I used SOK, mainly because they had a low temp cutout, which many don't, and because the top can be removed so you can balance or replace cells and BMS. All lithium is getting so cheap now that the being able to disassemble is less important, though.


All the lithium is getting very cheap, but I would not base just on cost. Read reviews and try to wade through the "bought and paid for" reviewers, as there are huge numbers of them writing this stuff.

[SteveJ]

A note on DC/DC charger. A 40 amp charger will draw somewhere around upper forties from the alternator.

Also, floating charge into a lifp battery is not recommended. I have a separate switch to control both a DC/DC charger and shore power charger to shut them down when desired. Our solar controller is Victron, nicely configurable. I set the float voltage at 13.3 with rebulk set at 13.0. Absorb is ten minutes at 14.2. The 13.3 float effectively is a no float on full batteries, then it gets dark.

Battery bank is three 100 AH Li Time group31 "Trolling Motor" batteries. High surge ability and cold weather shut down. Highly rated by Will Prouse.