Interrupted charger output

[creativepart]

If this was mine, I would chalk this up to something it would be handy to know, but since it's not causing a problem I could just let i go... for now.

But I recognize not everyone operates the same way.

[Winterbagoal]

Originally Posted by creativepart

If this was mine, I would chalk this up to something it would be handy to know, but since it's not causing a problem I could just let i go... for now.

But I recognize not everyone operates the same way.

I do.

[Morich]

Got agree on chasing some of the things we see. Perhaps we are getting too many nice little things to monitor stuff but we don't fully understand what the stuff we learn really means in the overall deal.
When working in a big company mobile shop, we used to occasionally get a new piece of test gear and not really know why or what we were supposed to do with it! That was before the internet and there was no way to go online and try to find what a new gizmo was even supposed to do, so we just kind of entertained ourselves on slow days!

[AJMike]

Clearing up some loose ends.

Heat is not the issue. I removed the top of the cabinet under the seats to allow air movement and drove about 20 miles. During that time I saw the exact same sequence of dips in the current and voltage as I saw before. I then stopped and felt the charger to see if it was hot. It was warm, but not hot, and I put the top of the cabinet back on and drove home.

The dips are all evenly spaced. If I can accurately time by counting seconds in my head (1 Mississippi, 2 Mississippi, ...) then the dips are all 60 second apart and last for perhaps 5-10 seconds before the current and voltage jump back to "normal". It is hard for me to believe that a sequence of voltage and current drops, spaced 60 seconds apart, are not designed to do exactly that so I assume this is normal operation. As such I will just leave it alone, for now.

When I arrived back home I again removed the top of the cabinet to check on how hot the charger was, and it was considerably hotter than the last time I checked. Had it been much hotter I could not have kept my hand on it without fearing a burn. The specs for the unit say that it is OK up to 122 F and I don't think it was that hot, but I think I need to ventilate the cabinet or move the charger to some location open to the air.

As for the suggestion that this is something to remember but to leave alone for now, I agree. My concern all along has been that something was failing in the unit and that I needed to gather enough information to return it, either for a replacement or for a refund. I will continue to pursue this with Renogy just to nail down as much information as I can, but as long as the charger is doing its job I can live with this kind of operation.

As for the Lithium batteries themselves, this trip was an eye opener. We spent 2 days in the Arizona mountains boondocking in the shadiest spot my wife could find and using the inverter for minor chores - watching dvd movies and heating water using the electric kettle. Since we got almost no solar power (something on the order of 15AH during the day) I consider the extra power in the BB batteries to have been essential. We would have had to run the generator for several hours with our old batteries to charge them or we would have easily run out of power. As it was I assume we could have spent one more day, but there is only so much time I can take doing absolutely nothing.

[Bones2003]

Going back to a comment from al1florida, you have both the DC-DC charger and the solar panels trying to charge your lithium batteries. Is it possible to temporarily disable the solar charger and then monitor for the problem? Perhaps there is a battle going on between the two charging circuits for overall control.

EDIT: I don't know your exact configuration but I guess it is possible that you have four ways to charge your house batteries:
1. From the engine alternator and the DC-DC charger with the vehicle engine running.
2. From the solar panels.
3. While plugged into shore power from some type of converter/charger.
4. While running from your generator.
So somewhere in this mix there is an answer to your situation and we still haven't really determined if it is a problem or not!

[creativepart]

Originally Posted by Bones2003

Going back to a comment from al1florida, you have both the DC-DC charger and the solar panels trying to charge your lithium batteries.

Mike do you still use the Zamp 30-amp PWM solar controller? That could the the charge controller pulsing... maybe? That's the P in PWM.

I took mine out and put in the Victron 100/30 MPPT solar controller and it stops charging completely if the batteries are being changed via some other method.

[al1florida]

Originally Posted by AJMike

Clearing up some loose ends.


The dips are all evenly spaced. If I can accurately time by counting seconds in my head (1 Mississippi, 2 Mississippi, ...) then the dips are all 60 second apart and last for perhaps 5-10 seconds before the current and voltage jump back to "normal". It is hard for me to believe that a sequence of voltage and current drops, spaced 60 seconds apart, are not designed to do exactly that so I assume this is normal operation. As such I will just leave it alone, for now.

The trends display image you provided is great. What you just wrote above, 60 seconds on and 10-15 seconds off is just what I see on the "trends display".
I think your next test should be turning off the DC to DC charger and see what the results are. I'll bet the dropouts go away, indicating the charger is turning off for whatever reason.


When I arrived back home I again removed the top of the cabinet to check on how hot the charger was, and it was considerably hotter than the last time I checked. Had it been much hotter I could not have kept my hand on it without fearing a burn. The specs for the unit say that it is OK up to 122 F and I don't think it was that hot, but I think I need to ventilate the cabinet or move the charger to some location open to the air.

I would expect that the DC-DC charger would be very warm to hot when you finished driving home. With the charger putting out close to it's max current of 40amps you are using it pretty hard.

To cool the charger You can buy a 12V computer muffin fan at Amazon for under $20. Mount the fan facing the charger. The fan only pulls about 0.2 to 0.3 amps.
Search Amazon for "computer muffin fan 12v dc". Or buy one at the "Best Buy" store near you.

Also the Victron Display image is great. It shows the battery voltage as 13.47 at what I assume is the time when the dropout occurs since the current is showing -1.9 amps. Makes me wonder what voltage the solar controller is putting out. I would have expected it to be higher than 13.47V. It would be good to check when the DC-DC charger is off and panels are in about the same amount of sun as when you took the snapshot of the Victron Display.

Very interesting that the "starting battery" voltage is at 14.79V. That is a lot higher than what I would have expected. I wonder if the charger can handle that high of voltage. The owners/install manual should have a specs section showing the max voltage.

[AJMike]

Originally Posted by Bones2003

Going back to a comment from al1florida, you have both the DC-DC charger and the solar panels trying to charge your lithium batteries. Is it possible to temporarily disable the solar charger and then monitor for the problem? Perhaps there is a battle going on between the two charging circuits for overall control.

EDIT: I don't know your exact configuration but I guess it is possible that you have four ways to charge your house batteries:
1. From the engine alternator and the DC-DC charger with the vehicle engine running.
2. From the solar panels.
3. While plugged into shore power from some type of converter/charger.
4. While running from your generator.
So somewhere in this mix there is an answer to your situation and we still haven't really determined if it is a problem or not!

Originally Posted by creativepart

Mike do you still use the Zamp 30-amp PWM solar controller? That could the the charge controller pulsing... maybe? That's the P in PWM.

I took mine out and put in the Victron 100/30 MPPT solar controller and it stops charging completely if the batteries are being changed via some other method.

Before I retired one of my jobs was to read computer dumps to figure out where the software went wrong and how to fix it. And I probably enjoyed that work as much as I did because I don't really like to not know what is wrong when something is not working properly. Even if I can't fix something I want to know why it is failing.

The thing I am uncertain about (Ha. I wrote that like there was only one thing) is how to disconnect the solar input to test this. As I understand it I can not just go on the roof and disconnect the plugs as they should not be either connected or disconnected while the panels are producing power. I should either do this at night (fat chance, doing this in the dark!) or somehow cover them so that they are not receiving any sunlight, and even then that does not disconnect the solar controller from the system, only the input power. Can someone suggest how to do this? I think it is worth trying.

[AJMike]

> I think your next test should be turning off the DC to DC charger and see what the results are. I'll bet the dropouts go away, indicating the charger is turning off for whatever reason.

The problem is that the charger is in the line from the alternator to the batteries and if I turn it off (and there is an ON/OFF switch) then there will not be any alternator power applied to the batteries. The only thing I could do then is press the "bridge" button that allows power from the starter battery and I don't think that is a good idea especially for any length of time.

> To cool the charger You can buy a 12V computer muffin fan at Amazon for under $20. Mount the fan facing the charger. The fan only pulls about 0.2 to 0.3 amps.
Search Amazon for "computer muffin fan 12v dc". Or buy one at the "Best Buy" store near you.

The charger is currently installed in the compartment that holds the water heater under the seat at the dining room table. That is not the problem it might seem to be since we almost never use the water heater and when we do the engine is not running.

The real issue is that I think the compartment may not have enough air to properly cool the charger and I have been trying to decide if I should provide an air flow to cool it or mount it outside the compartment. Both choices have issues.

If I want to cool it in its present location I really need to add vent holes on both sides to allow free passage of air and mount a fan. Your idea of a muffin fan is probably exactly right and should not be too expensive if I can find proper vent hole covers.

Mounting it outside the compartment is going to be difficult as I am not sure there is a good location to place it. The Fuse is not large and there are not a lot of open and available spaces where someone would not accidentally touch it.

Given those constraints it is probably best to try to figure out how to cool it where it is. Fortunately the hard work of installing it is already done and the rest should be easy (Easy? I know I am going to be sorry to have said that).

[AJMike]

Originally Posted by al1florida

Also the Victron Display image is great. It shows the battery voltage as 13.47 at what I assume is the time when the dropout occurs since the current is showing -1.9 amps. Makes me wonder what voltage the solar controller is putting out. I would have expected it to be higher than 13.47V. It would be good to check when the DC-DC charger is off and panels are in about the same amount of sun as when you took the snapshot of the Victron Display.

Very interesting that the "starting battery" voltage is at 14.79V. That is a lot higher than what I would have expected. I wonder if the charger can handle that high of voltage. The owners/install manual should have a specs section showing the max voltage.

The Zamp solar controller never seems to put out more than about 13.5 volts even though it is set on LiFePO4. I called them to ask why it is not putting out the proper voltage for Lithium batteries but they told me that it is acting as designed. Since the proper charging voltage for the BB batteries is above 14 volts that does not seem like a very good answer to me.

I should also mention that I have not looked at the solar controller display when running the engine. Of course I can not when driving but I have not stopped and walked back to look at the solar controller with the engine running. Perhaps that is something for me to do on the next trip, but when the Fuse is camped the solar controller output is about 13.5 volts. The Zamp manual gives the voltage range up to 14 volts but it never seems to get that high.

And you are correct in commenting that the starter battery has a higher voltage than I think it should have, and is probably being damaged by the charger. My plan when all of this other stuff is done is to turn off the DC-DC charger when it is not needed. That is, after the BB batteries are at or near full I will just switch it off and take it out of the circuit. The solar charger should then finish charging the batteries and not over-charge the starter battery.

Charging voltage from the DC-DC charger for the Lithium batteries is 14.7 volts according to the Renogy manual.

[Morich]

I do fish breeding in Texas where hot tanks are a problem so I've done several cooling fans using cheap parts. Thank god the humidity is low and evap cooling works well for tanks!
My source for fans is to collect several of the junk computers offered up on Craigslist, etc. There are various sizes and types of fans on desktops which can be converted to cooling fans very easy as they are 12VDC and need very little current so that almost any of the salvage 12VDC power supplies ( wall-warts?) is good for power. On your setup, you may already have 12Volt easy to get to it?
If you have the round (4inch?) vents on the furnace, adding a wooden box around the fan and a vent cover on each side might not show much or be tough to work out. Keeping in mind that it works best if there is a way to get air in when trying to get air out.
I think we can surely figure out some way to keep you busy!

[creativepart]

You can do a couple of things.

Test it at night
Put cardboard (blankets, anything) over the panels
Disconnect the controller at the batteries.

All sorts of ways to turn off the solar panels..

[Winterbagoal]

Originally Posted by AJMike

The Zamp solar controller never seems to put out more than about 13.5 volts even though it is set on LiFePO4. I called them to ask why it is not putting out the proper voltage for Lithium batteries but they told me that it is acting as designed. Since the proper charging voltage for the BB batteries is above 14 volts that does not seem like a very good answer to me.

I should also mention that I have not looked at the solar controller display when running the engine. Of course I can not when driving but I have not stopped and walked back to look at the solar controller with the engine running. Perhaps that is something for me to do on the next trip, but when the Fuse is camped the solar controller output is about 13.5 volts. The Zamp manual gives the voltage range up to 14 volts but it never seems to get that high.

And you are correct in commenting that the starter battery has a higher voltage than I think it should have, and is probably being damaged by the charger. My plan when all of this other stuff is done is to turn off the DC-DC charger when it is not needed. That is, after the BB batteries are at or near full I will just switch it off and take it out of the circuit. The solar charger should then finish charging the batteries and not over-charge the starter battery.

Charging voltage from the DC-DC charger for the Lithium batteries is 14.7 volts according to the Renogy manual.

While testing something unrelated in my Navion this afternoon, and while plugged into shore power to boot, my ZS-30A PWM display showed 14.7V. It happens, rarely, but "if no one is there to see it, does it actually make a display"?

[al1florida]

Originally Posted by AJMike

> I think your next test should be turning off the DC to DC charger and see what the results are. I'll bet the dropouts go away, indicating the charger is turning off for whatever reason.

The problem is that the charger is in the line from the alternator to the batteries and if I turn it off (and there is an ON/OFF switch) then there will not be any alternator power applied to the batteries. The only thing I could do then is press the "bridge" button that allows power from the starter battery and I don't think that is a good idea especially for any length of time.

My thinking here is not for you to turn off the charger and leave it off. You want to know if the current drop is being caused by the DC-DC charger or something else.
So turn off the charger for a few minutes or how ever long it takes to verify that you no longer see the Victron Display showing a big change in current.

It is my understanding from your posts, that the dropouts happen pretty much as soon as you start the engine and the charger starts charging your house batteries.

An additional test you could easily make is to take a multi meter and measure the voltage the alternator side of the charger and see if the voltage from the alternator is dropping at the time the Victron is showing the drop in current.

If you don't have a multi meter, they are available for under $20 at Amazon or big box hardware stores. You really need a multi meter when you own an RV for trouble shooting problems.

Another test you should make is to monitor the starting battery voltage on the Victron display. When you see the voltage up into the 14.7V range, turn off the DC-DC charger and see if the voltage drops or changes. Once you turn off the charger, be sure to leave the engine running for an additional 15 minutes or so to be sure the starting battery is fully charged and not causing the alternator to put out high charging voltage. Unless the starting battery has been discharged by something, just starting the engine doesn't drain the battery very much and it should be fully charged in less than 5-10 minutes, maybe in 2-3 minutes.

[AJMike]

Originally Posted by al1florida

My thinking here is not for you to turn off the charger and leave it off. You want to know if the current drop is being caused by the DC-DC charger or something else.
So turn off the charger for a few minutes or how ever long it takes to verify that you no longer see the Victron Display showing a big change in current.

I will do that the next time we are out in the RV, but keep in mind that the charger is on the direct line from the alternator to the batteries so if I turn it off the only input to the batteries will be from the solar controller and I don't see a current drop when stopped and the only input to the batteries is from the solar controller.

Originally Posted by al1florida

It is my understanding from your posts, that the dropouts happen pretty much as soon as you start the engine and the charger starts charging your house batteries.

Yesterday morning when we left the camp site it was perhaps 10 minutes before I saw this consistent drop in current and voltage. Up until then the output from the charger was relatively consistent at between about 38 and 42 amps. After perhaps 10 minutes I started to see the consistent drop in output.

That made me think that the issue was heat but the compartment containing the charger was open to the air and when I stopped and checked the charger it was only a little warm.

Originally Posted by al1florida

If you don't have a multi meter, they are available for under $20 at Amazon or big box hardware stores. You really need a multi meter when you own an RV for trouble shooting problems.

I have a multimeter and I use it around the RV and have thought about doing exactly what you are suggesting The problem has been that I am driving when I see this and there is no way for me to check the input to the charger. What I need to do is stop somewhere, leave the engine running and see if the charger output still "saw tooths" and, if so, then check the input as well as the output.

I wanted to do that when we arrived at our destination but by then the batteries were fully charged and I was no longer seeing any output from the charger.

Originally Posted by al1florida

Another test you should make is to monitor the starting battery voltage on the Victron display. When you see the voltage up into the 14.7V range, turn off the DC-DC charger and see if the voltage drops or changes. Once you turn off the charger, be sure to leave the engine running for an additional 15 minutes or so to be sure the starting battery is fully charged and not causing the alternator to put out high charging voltage. Unless the starting battery has been discharged by something, just starting the engine doesn't drain the battery very much and it should be fully charged in less than 5-10 minutes, maybe in 2-3 minutes.

I can also give that a try the next time we are out in the RV. As it is the starting battery voltage drops back to normal not too long after we camp.

[CharlesMoore]

I do not see in your initial question which Battle Born battery model you actually installed. What I am really after is the xC rating (like 1C rating ) of your batteries and the AH rating. It would seem that the 40A Renology would be a charging restriction for the BB when on shore power. Is the Renology only for the alternator?


I am more familiar with sailboating and their charger systems. Everyone who cruises off shore for very long is going to lithium. Lots of these boats have Heart (Xantrex) charging/inverting my 2000 systems charges at 100 A (if allowed by the charger) and on a 100AH Lithium rated at 1C it is perfectly ok to do so. My alternator is rated at 150 A as long as there is cooling airflow.


My Winnebago Journey coach has a heart 1500 Inverter/Charger and it will charge at 70 A as designed. The BB said it is ok to use my coach model Heart on their batteries as is. My alternator is designed for 100+ A and as temperature rises in the alternator the charging current decreases via the reduced voltage across the batteries as a builtin selfprotect.


I did not mean to hijack your thread but I do not see what the problem is if the extraneous equipment is removed.

[AJMike]

Originally Posted by CharlesMoore

I do not see in your initial question which Battle Born battery model you actually installed. What I am really after is the xC rating (like 1C rating ) of your batteries and the AH rating. It would seem that the 40A Renology would be a charging restriction for the BB when on shore power. Is the Renology only for the alternator?

I had 2 of the 100AH batteries installed. I am unaware of there being more than one BB model rated at 100AH so if there are more models I would have to go look at the batteries to be more specific.

The Renogy charger is only used for limiting the current from the alternator when the engine is running. As for the xC rating, I am not sure but I assume 1C.

Originally Posted by CharlesMoore

I am more familiar with sailboating and their charger systems. Everyone who cruises off shore for very long is going to lithium. Lots of these boats have Heart (Xantrex) charging/inverting my 2000 systems charges at 100 A (if allowed by the charger) and on a 100AH Lithium rated at 1C it is perfectly ok to do so. My alternator is rated at 150 A as long as there is cooling airflow.

I can not speak about marine implementations as I have no knowledge of what goes on there. My understanding from talking with the BB folks is that the DC-DC charger is to protect the alternator from putting out too much current for too long a time. I was told that the batteries themselves can easily take a 100 amp charge but that the alternator might have issues if the current was not limited.

Battle Born sells two different current limiting devices. One, a Battery Isolation Manager, is supposed to interrupt the current flow from the alternator on a regular basis to protect it and the other, the DC-DC charger, is designed to limit the constant current to a manageable (for the alternator) level. At least that is my understanding.

The alternator in my RV is rated at 210 amps although I would not expect that it would actually produce that much current at all, let alone at a steady rate.

Originally Posted by CharlesMoore

I did not mean to hijack your thread but I do not see what the problem is if the extraneous equipment is removed.

I don't know what extraneous equipment you are referring to. Perhaps you could clarify what specific devices you are discussing?

[CharlesMoore]

I appreciate the response. Yes, I may be conflating two different battery manufacturers - sorry.


Yes, I would assume 1C also. So I guess means your standard coach inverter/charger is working OK and it is not an issue in this thread plus the Renology is not within the shore power charging of the BB. This helps me to understand better.


If your alternator is a 210A device it should have plenty of capacity to charge the start batteries and the house batteries if a combiner is in place. My boat had a combiner that would charge the start battery to 13.8VDC (adjustable) then the house batteries would be connected until the max voltage of 14.1 (adjustable) would kick out the house batteries and the start batteries would reduce to about 13.8.


I am not sure if the coach has a real combiner or if it just parallels the house +start but the voltage will gradually climb until the house battery voltage is 13.8 ( I assume the start is the same voltage but the OEM guage is too inaccurate to tell).


The extraneous equipment I referred to is the Renology and the overheating issue may be a valid comment. The Victron should not cause and issue that I can see as long as the shunt is AOK. Many boats use these to measure battery i/o. Sorry to waste your time, I had an idea that the issue was something else.

[AJMike]

Originally Posted by CharlesMoore

Sorry to waste your time

Nothing to be sorry about. I am always glad to hear from someone who may be able to add some information to what I think I know and every little bit helps.

[AJMike]

Originally Posted by Morich

There are various sizes and types of fans on desktops which can be converted to cooling fans very easy as they are 12VDC and need very little current so that almost any of the salvage 12VDC power supplies ( wall-warts?) is good for power. On your setup, you may already have 12Volt easy to get to it?
If you have the round (4inch?) vents on the furnace, adding a wooden box around the fan and a vent cover on each side might not show much or be tough to work out. Keeping in mind that it works best if there is a way to get air in when trying to get air out.

I thought this was a good idea to keep the charger cool and looked on Amazon for fans. The ones I saw were rated as 12V but the voltage coming from the alternator is more like 13.7 volts and the Amazon descriptions say that when you get in that range you will seriously harm the life of the fan.

The setup seems simple enough - 2 vent covers for input and output air and a fan but the fan has to be able to handle 13.7 volts. Any suggestions for a 13.7 volt fan?

My electronics is rusty, not having done that kind of work since I left the military back in "the day". I have never been very handy with tools, having paid little attention during shop class in school, but this seems like a simple project if I can get past the voltage sizing issue.