First let me say I have little or no electronics background.

I am hoping to build a battery discharger, and I want this unt to cut off at 3.3v. (a little background here, I race radio controlled cars using 3.7v lipo batteries)

I somewhat understand and can read these circuits from my engineering background, however I have no earthly idea what I need to change to achieve this cutoff.

I'll be starting at 3.8 volts with approx 30amp load

thanks for the help

Nick

 

You should start your own thread, not hijack someone else's.

 

Hello,

You hijacked an existing thread:
OpAmp/Zener Low Voltage Cut-off Circuit
I moved your post to a new thread.

Bertus

 

you just want it to shut down entirely? or do something like send out a warning?
Racing RC cars, is weight a factor?
the simplest route (in my opinion), is get an arduino or other uC(microcontroller), measure the voltage, and shut it down with a relay (or use a transistor somewhere in the control circuitry to inhibit the thing)

just my opinion, I'm a fan of arduinos though

 

Is this discharger an in-car or out-of-car thing? Do you have a power supply other than the Lipo available for the discharger?

 

An off the shelf power meter with cut off.

http://www.ebay.com/itm/Programmabl...754?pt=LH_DefaultDomain_0&hash=item2a1d612f22

 

An off the shelf power meter with cut off.

http://www.ebay.com/itm/Programmabl...754?pt=LH_DefaultDomain_0&hash=item2a1d612f22

according to the listed specs that looks surprisingly accurate, but it would require a separate power supply, which I'm sure the OP doesn't want to carry around on a racecar

 

I didn't understand this to be an "on board" device.

"I am hoping to build a battery discharger,"

Seems more like a battery tester.

 

i took it as an onboard device that shuts the car down when the batteries hit a certain point, we should probably wait for op input rather than running away with this though

 

Lithium batteries can be ruined if discharged too far. I'd assume he wanted something to avoid that.

He's probably wondering where his thread went...