Help with solid state relay switch

ESK8 Electronics
1

Hey guys, so I purchased a 100A solid state relay to use with a spdt switch to turn my board on and off.

After connecting it, there is a voltage difference (4v) over the relay when off and my switch illuminates. When I turn it on, this voltage difference is subtracted from my actual voltage so I get a lower voltage (eg 24-4 = 20v)

This is not good as my low voltage alarm goes off and my esc will throttle down as it thinks the cells are low.

How can I fix this? or is my relay borked?

Cheers!!

2

Link to your SSR and a quick schematic of how you are using it?

3

Here is some more info in an endless-sphere thread: https://endless-sphere.com/forums/viewtopic.php?f=35&t=76479

Hope someone somewhere is able to help :stuck_out_tongue:

What I think is happening is that for some reason the ssr is acting as a resistor or something instead of a relay?

4

tldr

but based on what your a saying, sounds like your are seeing the Vgs of the fets inside the ssr (sign of lack of isolation).

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You can try putting the SSR on the low of the circuit

5

Tried putting it on the negative but still no go. When the ssr is off I can measure 7v across it, which means that 5 are going to the load. I’m going to get a new relay, I reckon this ones borked.

Cheers!