Voltage drops after going through Anti Spark Switch? /w picture

I’m trying my best to get this season of esk8ing started, but as it is my first time using a proper anti spark switch, I am a bit confused.

I soldered some XT-90s to Flier anti spark switch and connected it to my 10s battery which has been sitting at 36.3 volts since autumn. After connecting the switch I turned it on by twisting SW+ and SW- wires together. I decided to measure voltage in the other end to see if it worked and to my surprise the multimeter read 33.4V.

Is my surprise justified? Is it normal to have the voltage drop by nearly 10% after it goes through the switch? If not, what could be the cause? I looked for similar experiences in the forum, but couldn’t find any.

I included a “diagram” of my setup and what numbers I got when measured at different spots in the system.

If something is not clear, ask away.

If all solder joints from battery through switch are solid and you’re are still losing 3V, I would lean towards that being a faulty switch.

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Well, well, well… if it isn’t the consequences of my own actions…

Right after posting the thread, I went to disconnect the switch and I suddenly noticed -
the red and black wire coming out of the switch are NOT in fact LED+ and LED-, but LED+ and SW+, which means I had not twisted together SW+ and SW-, but SW- and LED-. I don’t know why this gave me this peculiar reading of 33.4V but I guess it doesn’t matter.

Long story short, after actually twisting SW+ and SW- together, the switch works as intended and I am getting a beautiful 36.3V out of it.


That’s a nice little “gotcha” thanks for updating!