Safety Power Switch suggestion

[RootedSuperuser]

This is my 3rd LUNA SPS and 2nd 52V pack due to them burning up. Anything other than this or the Vedder available?

I just cant afford to keep building new packs.

 

[JackFlorey]

How about just an 80V 100A breaker?

 

[RootedSuperuser]

So how does it work with an on/off switch?

 

[goatman]

if the controller has an on/off switch, do you really need that luna battery switch?
the breaker would just be an on/off switch and maybe used for anti-spark

 

[amberwolf]

This is my 3rd LUNA SPS and 2nd 52V pack due to them burning up.

Something must be causing the failures, so what specifically happens when the failure occurs? And just before?

Exactly how is the system used? (as complete a detailed description as possible)

 

[miro13car]

I think it is not indivdual cell related.
shoddy isolated cell interconnect wires/jumpers/, either too thin or bad isolation between wires inside this pack causes over heat and melt.
fuse there is useless, does not do the job.

 

[RootedSuperuser]

shoddy isolated cell interconnect wires/jumpers/,
either too thin or bad isolation between wires inside this pack causes over heat and melt.
fuse there is useless, does not do the job.

What?! .... Are you talking about, my pack build?!

You should hold off on comments like that and ask questions 1st.

 

[RootedSuperuser]

if the controller has an on/off switch, do you really need that luna battery switch?
the breaker would just be an on/off switch and maybe used for anti-spark

Even shark packs have an on/off switch ... Might be time to cannibalize an old pack.

 

[RootedSuperuser]

what specifically happens when the failure occurs?
And just before?
Exactly how is the system used? (as complete a detailed description as possible)

• Was riding on a smooth road surface using throttle.
  Lost power to about 50%.
  Completely last power, came to a stop.
  Saw smoke coming from the battery compartment, pulled the pack out.

This is the 3rd SPS that has failed and LUNA, this is a cheap knockoff of the original https://www.espritmodel.com/search.aspx?find=safety+power+switch ... If you don't buy the original, your always going to get compromised quality, this is why they call it a knock off.

Where LUNA screwed up is the shortcut they took building the SPS, its a single layer, not double board like the original.

They run half the amps through either of the circuit boards and mosfets .... Fails Safe.

Pardon my french, but, Luna fuked up by taking a shortcut in the circuit build, screwed their customer as a result. Squeezing all those amps (35) through a single layer build was just stupid of them to do. They took a well designed German built item and redesigned it to suit their needs, not the needs of the customer.

 

[miro13car]

What?! .... Are you talking about, my pack build?!

You should hold off on comments like that and ask questions 1st.
[/quote]

I am talking about horrible pictures at the top.

 

[miro13car]

What?! .... Are you talking about, my pack build?!

I am talking about horrible pictures at the top. pictures speak by themselves.

 

[RootedSuperuser]

I am talking about horrible pictures at the top.

That is my pack build ...
So you appear to be clueless as to the proper building of a pack with your original statement ...
But I don't expect too much from ignorant people that lives in Calgary ... This is why I live in Edmonton, better hockey and football and educated people.

 

[monster]

I see no padding in these pics. Without foam padding the battery will bang into the frame and errode the cell insulation causing a short circuit through the frame. And fire

 

[RootedSuperuser]

I see no padding in these pics.

Its in/on the case, not on the pack

 

[fechter]

I doubt the lack of padding had anything to do with the fire. The on/off switch thing just couldn't handle the current and acted like a fuse. A while back I worked on various designs for a main pack switch with controlled precharge. Doable but a lot of work.

The big solar circuit breakers work great but are huge.

I've searched and I have not found anything off-the-shelf that has the desired ratings and is still compact. With some BMSs you can use the BMS as a switch by adding a switch to trigger the thermal sensor line.

 

[RootedSuperuser]

With some BMSs you can use the BMS as a switch by adding a switch to trigger the thermal sensor line.

BRILLIANT! .... I never thought of this! And I still can have the on/off light with the 110V self locking flat switch.
https://www.aliexpress.com/item/32996630889.html?spm=2114.12010612.8148356.17.5c7e645fbI9Za4

 

[fechter]

With some BMSs you can use the BMS as a switch by adding a switch to trigger the thermal sensor line.

BRILLIANT! .... I never thought of this! And I still can have the on/off light with the 110V self locking flat switch.
https://www.aliexpress.com/item/32996630889.html?spm=2114.12010612.8148356.17.5c7e645fbI9Za4

It's been tested on few models. One trick is you may need to place a 470 ohm to 1k ohm resistor across the B- to P- terminals to make it reset without unplugging the controller. This could allow a small drain on the pack if there was a load. Another option is to place a push button in series with the resistor to prevent any drain when turned off and you push the button to reset it when turning on.