Renogy DC-DC 50A (Version 1) Major Scary Failure

[Dellmassive]

Ment to ask before....

Your chassis ground connection good?

Not corroded or anything?

The units been in for a while now.

Poor connections cause heat build up?

I've had it befor after using a van seat bolt as a ground..... The cable to ring terminal at the bolt had corroded..... A slight pull and the cable broke away from the lug.


Just something for you to check.

.

 

[Farnorthsurfer]

PM me with a pic of the.serial number etc, I'll raise a ticket for you.?

They need to be aware of what's happened. And may offer you a replacement unit.

It looks like the tracks have burnt, it's possible that something failed pulling less current than your supply fuse, causing a PCB burn. But then you say the supply fuse blew.?

So I would try to inspect every inch of the cables, and fuses and holders before fitting a new unit.. looks for burning or heat damage.

A 60A midi fuse needs 80,90,100A to actively melt or blow, ... So the supply cabling and fuse holder etc will have been subjected to very high current and heat.

Plus, also a consealed cable (run under carpet for example) has a much lower current rating due to heat build up that the same cable in free air.

Post pics of your install if you can.

Fuses, cable, battery connections etc etc.

Hi @Dellmassive thank for the interest, just spent 30 minutes raising a support ticket with Renogy but it won't post 'upload error try again later' and its just thrown away all the data I entered waste of time IMHO as its out of warranty by some margin anyway. I am not doing it all again.
Your welcome to raise a ticket if you want, good luck, I have posted a photo of the serial sticker as there is nothing secret there.

The system wiring is fine, inspected and tested, no damage to supply cabling or components. I over specified the cabling originally and the supply to house battery is less than 50cm long as it only goes round the battery. The alternator cable is also fine and there was no apparent overload on that side.
Sure the 60A supply fuse did its job and blew in the end but as you say there was burning of the PCB before it did.
The battery did what its supposed to and pushed out as much energy as it could to the short. Lot of energy in those things.
My trade is licensed aircraft engineer so I am pretty happy dealing with high amp DC systems.

I am hoping that the revised unit will not suffer the same fate. Just from the photos of the unit it looks like the binding posts have been revised. I wasn't too impressed with the way in which they connected to the PCB internally. And the internal cooling depends on thermal pads sticking to the rear heat sink, maybe they have improved this.
Anyway don't take yours apart or you will disturb the thermal connection!

I did look at the Redarc units and they do look good but the cost is twice that of the Renogy and I couldn't find any low temperature cut off feature built in. Not important in Oz maybe but vital in Scottish Highlands.
I am looking at replacing the 60A fuse with a DC circuit breaker so that I can cut the power manually if I smell burning again. Or possibly an Isolator switch, but there's not much space and its more wire junctions in the circuit. Any experience with those DC CB's @Dellmassive ?
I wil also look at the cooling but TBH its about as good as it can get where it is located. I may reduce the power output to 30A in the new unit as it doesn't really need to be 50A.

 

[shropschris]

Thanks @Dellmassive I will ping Renogy and see what they say but need the van back as have more trips planned. May well just buy another Renogy as it does everything I need it to do.
Hard to get high solar VOC input and low temp cut off all in the same unit.
For sure I think it was an internal failure of the unit, either a PCB joint or failed component.

They will replace it for free we, had a 1000w inverter fail again smelt burning plastic ext , I unplugged it all before it went up. Renogy replaced no issues they never asked for the failed one back

 

[Farnorthsurfer]

They will replace it for free we, had a 1000w inverter fail again smelt burning plastic ext , I unplugged it all before it went up. Renogy replaced no issues they never asked for the failed one back

Over two years out of warranty on this unit, but nice thought, if only I could make the Renogy support system work

 

[shropschris]

Over two years out of warranty on this unit, but nice thought, if only I could make the Renogy support system work

Yeh they are not the best in that regard

 

[Farnorthsurfer]

Quick question maybe @Dellmassive will know the answer to.
In the latest unit app with the BT2 transmitter can you see the internal unit temperature?
I only ever used the old app, I may have tried the new one but think the firmware in my older charger wouldn't drive it.

 

[Dellmassive]

re trip switches and breakers. . .

im not a fan of these. . . . well, the ebay/amazon versions that are available.



they have very small contact area internally and start to get HOT when you are pulling current.

i would always favour a decent correctly rated MIDI or MAXI fuse and holder . . plus a main isolator switcjh. . . again correctly rated.




eg:

60A MIDI fuser and holder.

https://amzn.to/3qLBedi

and.


a 12v 275A battery isolator switch.

https://amzn.to/3P8zdRK

..........................





the only exception to this is the good quality BLUSEA version of the trip switches that the marine industry use.

but again . . . they still have a smaller switch contact area internally so will heat up.

and of course they are way more expensive than a MIDI fuse setup.

https://amzn.to/3P5eTRw

+++++++++++++





BLUESEA also do battery isolator switches. . .

https://amzn.to/3EdxZOR

.

 

[Farnorthsurfer]

re trip switches and breakers. . .

im not a fan of these. . . . well, the ebay/amazon versions that are available.



they have very small contact area internally and start to get HOT when you are pulling current.

i would always favour a decent correctly rated MIDI or MAXI fuse and holder . . plus a main isolator switcjh. . . again correctly rated.




eg:

60A MIDI fuser and holder.

https://amzn.to/3qLBedi

View attachment 210538


and.


a 12v 275A battery isolator switch.

https://amzn.to/3P8zdRK

View attachment 210539




..........................





the only exception to this is the good quality BLUSEA version of the trip switches that the marine industry use.

but again . . . they still have a smaller switch contact area internally so will heat up.

and of course they are way more expensive than a MIDI fuse setup.

https://amzn.to/3P5eTRw

View attachment 210540



+++++++++++++





BLUESEA also do battery isolator switches. . .

https://amzn.to/3EdxZOR

View attachment 210543




.

Thanks, yeah agree with all you say there. I debated fitting the isolator during installation but decided against it, "Why would I need to turn it off" I wondered to myself
There is not a lot of room in which to squeeze an isolator switch and of course its more joints in the circuit, but I will take another look at fitting one.
All my parts such as fuses and switches came from 12Volt Planet as quality seemed to be better than a lot of the Amazon/eBay sellers.

 

[Dellmassive]

this is how i have mine setup. . .

DC50S, with SB50 Anderson connectors, which are rated at 50A,

so i current limit the charger to stop the conectors heating up.






using a 60A MIDI fuse under the seat base as a connection point, on the OEM cable that's fed from the SA Fuse box under the starter battery, which is fed by a 100A MIDI fuse.










I've used a seat base bolt as a chassis ground via a Victron smart shunt.



the main leisure battery is a Roamer SB230G3 under the drivers seat. .

this is connected . . . .

Battery --> 200A MAXI fuse --> 12v battery isolator --> link cable to passenger seat base --> secondary MIDI fuse box -->60A MIDI fuse --> Anderson liunk cable to the Renogy charger.






.

then checking the thermals under load. . .



the charger heatsink gets warm . .






+

you can see the cables warming and fuse holders etc. . .



+

the battery stayed well cool . .




.

here you could see an issue with this MIDI fuse. . . it was getting well hot.











i love these thermal cameras. . .

but you don't need them, you can do the same just using the back of your hand to check for heat above ambient. . . run up the system under a full expected load.

then run it flatout for 5,10,15,30,60mins - whatever.

and keep checking all the components of the system for heat build up, - for my test above i loaded up the 1000w inverter with a 1000w electric heater,

that pulled around 100A from the battery alone,

then with the engine running, this draw dropped to 50A ish with the other 50A coming from the DC-DC charger. ( with the renogy set to 50A)


after all the testing, i dropped the Renogy 50A down to 30A to keep everything cool from the DC-DC charger front.

 

[Farnorthsurfer]

My unit was set up with solar always on so was limiting to 25A anyway. As I had a solar isolator switch I would occasionally turn solar off and charge at 50A which I verified on the app. As you say checking by hand, I never found any significant hot spots. The heat sink didn't really get warm to the touch during testing but its not like I stick my hand under the seat every day.
I think either a component on the PCB failed and sent it to hell or a joint failed on the PCB and melted the rest of it.
A system control fail might be more likely because its gone in more than one place on the PCB.
Anyway, waiting for the new unit to arrive.

 

[Dellmassive]

FYI, cased raised with Renogy (@Farnorthsurfer & @Dellmassive )

 

[roadtripper]

From experience in boats steer clear of the "turret" type of isolator.

What's not obvious is that it's the "turret" bit that holds the "key" down to keep the sprung contacts closed. If you mount it in a place where the turret can get knocked and snapped off then no power.

One of the yachts I used to charter had 2 of them under the chart table for engine and hotel banks - and they were forever getting smashed off by people falling and kicking the turrets off in a decent sea.

 

[Farnorthsurfer]

Thanks to @Dellmassive for his perseverance we received a reply from Renogy support today regarding my burnt out 50A unit. They were very apologetic but as the unit was well out of warranty they offered me a 6% discount on a future purchase.
I also received the new version 50A unit that I ordered the evening the old one failed. Good delivery direct from Renogy UK, no complaints on ordering service.
When I opened the box it was clear that they have made a number of changes to the unit. The first thing is that the rear heat sink is twice the size of the old one making the new unit much deeper than the old one. I am not sure if it will fit in the same location without modification.
The second thing is that in the box they have included both a solar MC4 fuse cable and a huge ANL 60A fuse holder and fuse.
Lastly the instruction manual is decidedly more detailed than the old one and includes a lot more information on cooling such as 6" of clear space above and below the unit. They also say the unit should be mounted vertically, in the old manual it could be flat or vertical.
The ANL fuse is one of those massive gold plated look at me ICE parts and I don't think it will fit in my system so will probably just use the old midi fuse again.
My system is already solar fuse protected at the back end near the panel so I don't need the supplied one but its nice to have it provided if you are building it up.

So conclusion, which is informed supposition is that my original version one unit overheated internally leading to component fail and burning, the 60A house battery supply fuse tripped as designed stopping the unit burning up even further. Probably as a result of a number of these failures Renogy seem to have upgraded the cooling and supported the installation of decent fusing to protect the unit and vehicle. The additional instructions support the way in which the unit should be fitted to improve cooling.
I can't be definitive about this as it doesn't work anymore LOL but I also think the firmware in the original unit doesn't support the Renogy Home app just the older app with no setting parameters.
When I get this one installed, if it fits I will dial down the amp output to try and reduce the heating. It will be fitted as the other one is at the front of the seat base vertically with the house battery behind it. There are some pictures of my install on my build thread, link below.

Thanks to @Dellmassive for his input and a maybe some comfort to people like @Cool Carlos who are fitting these units in their pride and joy.

 

[Chris_t6.1]

Thanks to @Dellmassive for his perseverance we received a reply from Renogy support today regarding my burnt out 50A unit. They were very apologetic but as the unit was well out of warranty they offered me a 6% discount on a future purchase.
I also received the new version 50A unit that I ordered the evening the old one failed. Good delivery direct from Renogy UK, no complaints on ordering service.
When I opened the box it was clear that they have made a number of changes to the unit. The first thing is that the rear heat sink is twice the size of the old one making the new unit much deeper than the old one. I am not sure if it will fit in the same location without modification.
The second thing is that in the box they have included both a solar MC4 fuse cable and a huge ANL 60A fuse holder and fuse.
Lastly the instruction manual is decidedly more detailed than the old one and includes a lot more information on cooling such as 6" of clear space above and below the unit. They also say the unit should be mounted vertically, in the old manual it could be flat or vertical.
The ANL fuse is one of those massive gold plated look at me ICE parts and I don't think it will fit in my system so will probably just use the old midi fuse again.
My system is already solar fuse protected at the back end near the panel so I don't need the supplied one but its nice to have it provided if you are building it up.

So conclusion, which is informed supposition is that my original version one unit overheated internally leading to component fail and burning, the 60A house battery supply fuse tripped as designed stopping the unit burning up even further. Probably as a result of a number of these failures Renogy seem to have upgraded the cooling and supported the installation of decent fusing to protect the unit and vehicle. The additional instructions support the way in which the unit should be fitted to improve cooling.
I can't be definitive about this as it doesn't work anymore LOL but I also think the firmware in the original unit doesn't support the Renogy Home app just the older app with no setting parameters.
When I get this one installed, if it fits I will dial down the amp output to try and reduce the heating. It will be fitted as the other one is at the front of the seat base vertically with the house battery behind it. There are some pictures of my install on my build thread, link below.

Thanks to @Dellmassive for his input and a maybe some comfort to people like @Cool Carlos who are fitting these units in their pride and joy.

Thanks for the detailed update! Have been lurking and reading with interest

 

[Farnorthsurfer]

Quick question maybe @Dellmassive will know the answer to.
In the latest unit app with the BT2 transmitter can you see the internal unit temperature?
I only ever used the old app, I may have tried the new one but think the firmware in my older charger wouldn't drive it.

If anyone was wondering I can now answer this. The Renogy Home app shows the battery temperature (sensor bulb) and what it calls MPPT temperature which I assume to be the main PCB in the unit.
I will keep an eye on this temperature on my next long journey which is on Monday to see how hot it gets on a run.
The maximum charging amps have been set to 30A combined which should leave some design headroom for heating.

 

[Farnorthsurfer]

Tested on a four hour journey down to Loch Lomond today. Leisure Battery was charging at 30amps for about 45 minutes and I was checking the temps every so often. Ambient temperature around the battery was about 21 degrees. The DC-DC MPPT temperature varied between 28 and 40 degrees rising during the bulk charge and dropping below 30 again when it switched to maintenance charge. It also seemed to be charging a few amps from alternator and a few from Solar on maintenance but I didn’t make any notes on that performance really.
So pretty happy with that, should keep the unit in a sensible range even if the ambient temperature goes up to 30 degrees.
(Sure the old unit was restricted to 25A when Solar was on. This one had no problem pumping 30A from the alternator with Solar switched on. I have restricted it to 30A in the app.)
Anyone have any questions on this G4 unit I will do my best to answer them.

 

[Jim Rey]

Thanks to @Dellmassive for his perseverance we received a reply from Renogy support today regarding my burnt out 50A unit. They were very apologetic but as the unit was well out of warranty they offered me a 6% discount on a future purchase.
I also received the new version 50A unit that I ordered the evening the old one failed. Good delivery direct from Renogy UK, no complaints on ordering service.
When I opened the box it was clear that they have made a number of changes to the unit. The first thing is that the rear heat sink is twice the size of the old one making the new unit much deeper than the old one. I am not sure if it will fit in the same location without modification.
The second thing is that in the box they have included both a solar MC4 fuse cable and a huge ANL 60A fuse holder and fuse.
Lastly the instruction manual is decidedly more detailed than the old one and includes a lot more information on cooling such as 6" of clear space above and below the unit. They also say the unit should be mounted vertically, in the old manual it could be flat or vertical.
The ANL fuse is one of those massive gold plated look at me ICE parts and I don't think it will fit in my system so will probably just use the old midi fuse again.
My system is already solar fuse protected at the back end near the panel so I don't need the supplied one but its nice to have it provided if you are building it up.

So conclusion, which is informed supposition is that my original version one unit overheated internally leading to component fail and burning, the 60A house battery supply fuse tripped as designed stopping the unit burning up even further. Probably as a result of a number of these failures Renogy seem to have upgraded the cooling and supported the installation of decent fusing to protect the unit and vehicle. The additional instructions support the way in which the unit should be fitted to improve cooling.
I can't be definitive about this as it doesn't work anymore LOL but I also think the firmware in the original unit doesn't support the Renogy Home app just the older app with no setting parameters.
When I get this one installed, if it fits I will dial down the amp output to try and reduce the heating. It will be fitted as the other one is at the front of the seat base vertically with the house battery behind it. There are some pictures of my install on my build thread, link below.

Thanks to @Dellmassive for his input and a maybe some comfort to people like @Cool Carlos who are fitting these units in their pride and joy.

I would have been less inclined to buy another unit from them after your experience. From what I have read in this thread you might have had a fire in your vehicle. I have a 50aH Renogy LIP04 battery that has died on me after only 6 months of very light use. They are giving me the severe runaround on the replacement whcih three weeks later shows no sign of being sent despite them promising it would be. Having read reviews on TrustPilot there are a lot of very unhappy people out there with Renogy. I would never buy anything from them again based on my own experience.

 

[Dellmassive]

I would have been less inclined to buy another unit from them after your experience. From what I have read in this thread you might have had a fire in your vehicle. I have a 50aH Renogy LIP04 battery that has died on me after only 6 months of very light use. They are giving me the severe runaround on the replacement whcih three weeks later shows no sign of being sent despite them promising it would be. Having read reviews on TrustPilot there are a lot of very unhappy people out there with Renogy. I would never buy anything from them again based on my own experience.

What are you replacing it with?

 

[Jim Rey]

What are you replacing it with?

Don't know yet. Going to give Renogy until Wednesday next week although hope is fading fast that they will actually honour warranty. After that, I will look around. Trouble is, all of these batteries are made in China, unless someone knows different. There are several providers on Amazon. Basically, the Renogy warranty is not doing me much good at present. I spent over £550 with Renogy, swapping out my CTEK 250sa and my AGM battery to make my vehicle lighter and my 12v system more efficient. I wish I had just stuck with my previous AGM/CTEK system which was working fine.

 

[roadtripper]

Trouble is, all of these batteries are made in China, unless someone knows different.

The majority of the cells are made in China yes, but that's not always where the battery (several cells, BMS, case etc) is assembled.

For instance I believe (but haven't confirmed) that Fogstar do the assembly in the UK.