Zero-Draw, Solid State Contactor w/Precharge (Arduino)

[Alan B]

Very nice design here, Patrick. I especially like the mechanical/heatsink setup. I used a switch similar to this on a solar controller I designed some years ago with a Tiny25. Lots of projects need a nice solid state switch.

Good luck in your jobhunt.

 

[friendly1uk]

Sorry if this has been said, but I couldn't read all 17 pages just to find out.

Many packages exist that could do this. Here is just one suppliers list, but there are control voltage issues. They are from logic to 32vdc. Such a low draw and wide range device will likely just need a voltage divider circuit though(two resistors). Cost is daft but it's very simple. They used to start at around $50 but that was some years ago. They get quite a bit of use in street lighting.

http://www.crydom.com/en/Products/New.shtml

Edit: Presuming you have a bms, you might just want to shut that down. Blagging low voltage should cost pennys.

Sorry again if all this has been said

 

[Kin]

Method's is a lot nicer than those

 

[Alan B]

Most of the solid state relays are not suitable, it would be useful if folks found some that were:

1) inexpensive (or at least not high cost)
2) 50-150 V DC capable on the output
3) 50-400 amp output rated
4) could handle capacitive/inductive load turn-on and turn-off
5) did not dissipate much power

There may be some out there, so show them.

 

[powersupply]

How about this one, for $19? Fully programmable. And it will work up to any current you like, with my solution.
http://www.bmsbattery.com/smart/330-lifepo4lithium-ion-smart-bms-for-513-cells-in-series.html

.. we already bought 20 of those - AND the programmer to go with them - and I have already posted about how the design is inferior. That first link - yea - I reverse engineered the circuit board and guess what? The main capacitor on the board is not even connected due to poor PCB fabrication.

The first link - the balancing scheme is so poor that it basically does not balance batteries. If you investigate the method it uses you will find that for anything other than new, perfect, batteries the BMS will terminate high current charging nearly every time before the pack is balanced.

Dear Methods, I searched up and down but could not find your postings in regards to the mentioned SmartBMS. I searched for 'SmartBMS' and 'Smart BMS' etc. Even tried google.
Please be so kind and point my nose to your findings.
Thanks!

 

[rodgah]

I gather these went out the window with methods departure? .

Is there anyone else doing something similar I haven't happened to stumble across?

 

[Alan B]

Not exactly but similar requirements and a different approach:

http://endless-sphere.com/forums/viewtopic.php?f=14&t=54225