Quantcast

Will the Estes PS II Launch Controller handle 12 volts?

The Rocketry Forum

Help Support The Rocketry Forum:

Cape Byron

The BAR formerly known as Skippy-2
TRF Supporter
Joined
Aug 4, 2019
Messages
663
Reaction score
541
Location
Northern Rivers, Australia
Title says it all. I may have the opportunity to grab one of these controllers at a good price. The manual states you can use an 11.1v LiPo via the internal JST socket. Has anyone used a 12 volt motorcycle battery (or similar) connected via the JST? Looks like a nice controller for the kids to drag race with.
 

BEC

Well-Known Member
Joined
Feb 19, 2009
Messages
3,298
Reaction score
342
Location
Auburn, WA
Why bother? A 3s LiPoly will sink as much current as a 12V lead acid battery, be lighter and has no acid spill risk.

The real limitation here is the current-handling capability of the little red JST connector. Thankfully lighting an igniter or three only takes a second or more often a fraction thereof. Continuously those things are good for maybe 4-5 Amps tops.

All that said, I'm sure the LED and the rest of the guts of the PSII controller will handle a nominal 12V lead acid battery without going up in smoke from the slightly higher voltage (13.8V fully charged for the lead acid battery vs. 12.6V for the LiPoly).
 

Cape Byron

The BAR formerly known as Skippy-2
TRF Supporter
Joined
Aug 4, 2019
Messages
663
Reaction score
541
Location
Northern Rivers, Australia
Why bother? A 3s LiPoly will sink as much current as a 12V lead acid battery, be lighter and has no acid spill risk.
<snip>
Simple economics. I have the motorcycle battery (sealed) sitting here. :)

Just wondering if anyone else had done it.
 

BEC

Well-Known Member
Joined
Feb 19, 2009
Messages
3,298
Reaction score
342
Location
Auburn, WA
Fair enough. The limitation, as I say, will be the JST connector itself and the wiring you use to connect that socket with your battery. Especially for clusters, heavier gauge wiring is better, as I'm sure you know. If I were doing it I think I'd make a battery lead out of at least 16-gauge wire and splice it to one of those pre-made male JSTs with only a couple of inches of the supplied lead so as to keep the ~22-gauge wiring short. At the battery end I'd crimp on ring or spade terminals so that you can use the screws in the battery terminals for a solid connection. Then make a hole in the battery door (cut off a corner?) and a knot in the wiring between the splice and where it comes through the battery door to support/provide strain relief and to keep the little JST from getting disconnected just with the weight of the wiring.

I should have figured that motorcycle batteries were sealed these days.....it's been a long time since I've owned a motorcycle.

I guess we'll see if anyone actually has done this, eventually.
 

BEC

Well-Known Member
Joined
Feb 19, 2009
Messages
3,298
Reaction score
342
Location
Auburn, WA
Oh dear.....it's been sitting without being without being charged, eh?

This is what I'm using. One charge every few months....and I use this controller pretty much every time I go flying on my own, which this year has been quite a bit. As you can see from my scribblings on the battery, it's been around awhile - I've had it for over 14 years. It's probably not much good to fly a plane with anymore but it fires one or more igniters just fine.
IMG_465077217.JPG
 

Cape Byron

The BAR formerly known as Skippy-2
TRF Supporter
Joined
Aug 4, 2019
Messages
663
Reaction score
541
Location
Northern Rivers, Australia
Oh dear.....it's been sitting without being without being charged, eh?
It's been sitting connected to a trickle solar charger, and I was blaming the solar charger for low voltage. :mad:

No matter. The controller will be here next week and I'll go LiPo shopping. Thanks for your input.
 

Cape Byron

The BAR formerly known as Skippy-2
TRF Supporter
Joined
Aug 4, 2019
Messages
663
Reaction score
541
Location
Northern Rivers, Australia
Controller has arrived, no box or instructions (like I care) but brand new. Bought it for $10AUD ($7US) on Fleabay and they retail at $90AUD ($64US). Time to go LiPo shopping.
 
Top