Safety Link/ Links

Hi Guys

For my latest creation i will be using 2 voltage power rails 12v and 24v (see profile pic)
Where would best place to put safety link /links ?

Cheers Froggy

The circuit as drawn on your profile will not provide 24 volts where it says 24 V. Also you have batteries in parallel. If they are nicads you need to be sure they are at the same state of charge before connecting them in parallel. Dont try to charge them in parallel.

Sticking a wire between the neg of M1 and the pos of M2 should ........ I think .... give you 24v on M3.

Thanks for response guys...oops i missed a wire !!! new pic on profile...still cant work out best place for safety link/links ??

I think that youll need 2 ... doubled up to make a single link.

One link in each off the top lines of your drawing and before the speedos ........I.E. Just before the + shown in your drawing and just before the - shown in your drawing.

Hi Alan and all

I think between us we have come up with the best solution ! (see profile pic) comments and recomendations welcome .

Cheers Froggy

Yup ...that should do it.

Agreed, that covers all the requirements of the removable link rule. Dont forget your power light... wire a 24v LED across the downstream sides of the links or across the item marked as 30A speed controller on your diagram.

his power light has been put in the diagram by the link!

Slightly OT but are you going to optoisolate your ESCs from your receiver? (Isnt the signal ground normally connected to the supply ground for ESCs, creating a ground loop?)

Whoaaa !!!!!(recommendation goes over my head )!!!

As long as the bloody thing works i will be happy..As many of you that have seen my bots..they always look good but never work properly. :lol:

Cheers Froggy

Depending on how your speed controllers are wired internally, you might end up letting the magic smoke out!

The negative supply of M1s speed controller is 12V higher than the negative supply of M2s speed controller. If the black wire that goes from your speed controllers to your receiver is also connected (internally) to the negative supply to the speed controller then both negative supplies will be connected together, via the receiver.

If the black wire isnt connected to the negative input then you dont have a problem, but if it is, somthing will have to give, probably a pcb track in one of your speed coontrollers. I thought you might want warning :-)

Ill check my electronizes later when I get home to see if they have signal ground connected to their negative supply but I think the IFI victors have them connected and some other ESCs do.(http://forums.delphiforums.com/n/mb/message.asp?webtag=THERFL&msg=3706.8&search=yhttp://forums.delphiforums.com/n/mb/...3706.8&search= y)


Hope this helps

Hi Mark

Thanks for warning info....I will be using standard 15a elecronize speed controlers in this bot so look forward to hearing your findings.

Cheers Froggy

Ive just checked my 30Amp electronizes and the negative supply from the battery to the speed controller is connected to the black wire to the receiver.

Assuming your 15A ESC and 30A ESC in your wiring diagram are all electronizes, I think you might have a problem.

Possible solutions (off the top of my head, might not be practical):
1. Use an optoisolator between the receiver and the ESC.
2. Modify the ESC pcb to remove the connection
3. control the ESC using a mechanical connection (servo driving a pot or similar)
4. use two receivers (electricaly isolated)
5. use relays instead of ESCs
6. use ESCs that are already isolated.

Simplest solution is probably to get an optoisolator. The only ready made solution for RC I can find is the zero glitch module (£8.99) sold here: http://www.goldstarstockists.com/tamiyaparts/tpx/electronicgadgets.htmhttp://www.goldstarstockists.com/tam...nicgadgets.htm
I wouldnt have thought its too hard to build your own using a cheap IC though. Somebody else whos had a go at this could probably chip in with some advice here.

Hi Mark

Well it did look good on paper !!!!:lol:

1) Use an optoisolator between the receiver and the ESC. .....£9.00 for each ESC....£36 total...
2)Modify the ESC pcb to remove the connection ..then would have to have seperate bat pack for rx
3)not practicle
4) same as 2)
5) this is for a high speed spinner bot so need all control i can get
6) got to use what ive already got

Might be cheaper and easier to run 24v gold as opposed to 12v drill motors....or run drill motors at 24v and smell the smoke !!!

Cheers Froggy

I just thought - some people have had success with running 12V motors on 24V, but using rate limiting in the radio so you can only get a maximum of 50% throttle. Its still harder on your system than running it on 12V but it does reduce motor heating.

Might save you from frying your motors.

Hi Froggy
Or you could do what I have done in DragonStrike. One circit for the drive and a different 1 for the weapon.

Hi Big Tone and all

i remember you showing me dragonstrikes circuit at leicster with its 2 circuit design....if i was using 6 x 12v 800ma batt packs what would be best configuration....ie...4x12v paralled for drive 2x12v series up to 24v for disk.. or 4x12v series up to 24v for disk and 2x12v paralleled for drive..
in other words which would take most power to run ..drive or spinning disk ???(drive being orrible lil 9.6v woolies type drill motors)

Cheers froggy

Hi
On DragonStrike I use 2 x12v 3300 in series for the disc and 2 x 7.2v 3000 in series for the drive.

Hi again
The Disc takes the most power on DragonStrike it just about lasts 1 fight but the EV at 1-1 does suck power. The drive will do 2 fights before i need to charge them.

Hi Tone

Good..that just about does it !!! now to get buildin (pic on profile)

That looks good Tony, just do something about the exposed wheels and youve got a winner.

You mean like this young Ed ??? (updated pic)

Keep drinkin the beer will put hairs on ya chest !!!:mrgreen:

Cheers Froggy

Much better :)

Mmmm, interesting machine there Tony... Very interesting indeed! :)

(Cant wait to see it try to make a quick turn with that disc at full chat!! :wink:)

Hi guys

Thanks for comments...Young Ed..big Tone...and the exalted one mr Smith.
Just weighed spinner disk and plate mountings..hmmm 3.5K...batteries and controllers to add....might be a bit fat...but then again all my botts generally are..
Ill start drilling holes and hope its ready for easter...:lol:

Cheers Froggy

Thats pretty nice! Maybe you could send a practice run video to us! :)

Hi Kody
Test video huh !! i have just got to grips with digital photos let alone video !!!

Cheers froggy

Hi

What the hell is a vapour bot ????...new class ??

Derives from http://en.wikipedia.org/wiki/VaporwareVapourware...

Much like my concept vapour Wedginator, see the basic shape on my profile :wink:.

Tony - Dont worry, Im no genius with video either. :lame:

Ahhh...gotcha

Pretend bot !!!....with pretend radio ..batts..motors and only suffers pretend damage in battle....much cheaper on the pocket !!!
:mrgreen:

Cheers froggy

Hah, yeah check the FanFic section Tony, thats where our pretend bots participate in pretend tournaments :)

And no lost change. :proud:

Anyway, have you thought of what colours to paint it with? :)

Hi young Kody

Paint !!!!! nah look at new pic....duk tape silver
and Titanium grey :)

Cheers froggy

Ah, it seems like S3 shrunk to featherweight proportions. Hope it goes far! :)

Something, to add thinking about Geoffs post above, what are your wheels made from cos they dont look that grippy. Which will not help when that thing is at full pelt.

Dunno why we are helping you, it looks like it could make a nice mess of DB5, lol

DB5? Err...

Hi young Ed
Wheels are kinda hard /soft.. plastic/rubber if they are any bother will just glue timing belt over the top....ahh S3,,,thats the bot i was thinkin of...but didnt it have exposed wheels ???

Cheers froggy

yeah, they got chewed up by Razer. If you encounter a FW chompbot, then youre in trouble. But if youre an awesome driver, then you should be OK. :)

Hi Kody

I have been described as a lot of things in my life but awesome driver is not one of them !!!
:rofl:

Cheers froggy