Diy anti spark switch?

there is always an easy way… thanks!!!

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^following on from this, you want a SPDT switch

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and…

in your drawing you show a 3 pole switch, if the switch is left in position 2 for more than a moment the resistor will blow

if you can’t find a spring-loaded switch that is either in position 1 or 3, and only passes momentarily thru position 2, you are doomed to have failures

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More trouble than what it’s worth.

Wait for haggybaord antisparks to come out, they will have fully effective smart functions (no push button needed) and be very attractively priced.

Yes they ARE coming out, I can’t say exactly when until the testers are ready to write their reviews.

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Is there anything haggyboard cant do? Hey HB dual 6 vesc please.

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Think that may exist

Its gigantic though.

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This is my relay-based antispark.
Slowly charges capacitors when button is pressed, capacitor’s voltage turns on transistor that energizes the relay.
But if switch is not toggled, relay does not turn on

Thanks for the tips and measurement!
Why would the resistor blow? Once the capacitors are fully charged (a matter of few miliseconds) the current goes to zero, isn’t it? The resistor only limits the initial infinity current.

Theoretically, I can leave it all at state 2, even drive with it, but the fuse (I was thinking 10A?)
Will blow once driving so the resistor wouldn’t blow either that way…

Correct me if I’m wrong

About the switch, what is SPST? I really just put the chrapest one I found with 3 states… I have no idea what is it

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Please elaborate

Thank you!
Why get rid of the fuse?
I was thinking about it to protect it from over current on that state, in case state 2 is stuck or helded too long

I doubt I’ll find one, the hard part was finding something cheap but also heavy duty for high current…

I really don’t understand why it matters
What happens if you leave it on state 2 for long period of time

Once capacitors are loaded no current is flowing unless I run the motors

using your terminology not mine… the switch you posted has only two states not 3 (thus SPST) single pull single throw, you need a SPDT single pull double throw switch to get 3 states…

The resistor will heat (really hot) up when you allow full current to flow thru it other than momentarily…

look at an XT90S that has a resistor in part of the plug that allows current to pass thru MOMENTARILY as you engage the plug… if you leave it plugged in only partially the heat of the resistor will melt the connector…

follow me?

Interesting!

Maybe I’ll put something temporary for now and when it arrives I’ll upgrade to that, thanks! Is there any link to follow that?

What exactly do I see?

He said he used flipsky anti spark switch

if it were as simple as a cheap switch and a resistor, why do you think everyone doesn’t use one?

this is a schematic of a proposed anti-spark…


why? it answers the problem…

you want cheap and effective and almost fool-proof? use an XT90s loop key like 99% of us do…
linked above…

I hope this helps

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Properly rated power relays are expensive AF tho :(.

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Hmm still not,

Lets leave a side for a moment my drawing and use the XT90S as the reference.

Lets assume Im half plugging it so the circuit is closed with resistor in series… (For a long time)

Resistor of ~5ohm in series with capacitor
At initial moment, capacitor’s resistance (impedance) is zero, so total resistance is 5 ohm, so lets assume we have 40v, thats 8amps flowing…

Moment later, capacitors are loaded, so current is less than 8amp…

It starts with 8A and goes down to 0A in a charging time of 5tau where tau is RC so 5ohm times 220uF times 5tau, we get total charging time of ~5ms

After 5ms current is zero in the RC circuit

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sorry I tried my best…

I’d suggest you PM @professor_shartsis he is much better at explaining things than I am

good luck

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I just realized I’ve put a wrong link

This is the one I was looking at:
https://www.amazon.com/DaierTek-Toggle-Switch-Automotive-Position/dp/B07SN7BY8V/ref=mp_s_a_1_5?keywords=50a+toggle+switch&qid=1581496394&sr=8-5

Thanks for pointing out the terminology of SPST and SPDT… its now easier to find one

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Effort is much appreciated man! Thanks!

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