skotl
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Query to the electrical / electronics folks re DC to DC SSRs. I've got a unit pretty much exactly the same as the one shown here: https://lorentzzi.com/how-to-wire-a-solid-state-relay/#pp-toc__heading-anchor-4
Image of it in action:
And here's how my circuit is wired up:
The control is from an ESP32 (like an Arduino) and it supplies 0V for off and 3.3V for on.
The load is a computer fan, with 15V wired into the output part pin #1 of the SSR. 0V rails are shared across the fan and ESP32 circuits.
The SSR appears to visibly work as expected - the red LED comes on when I apply 3.3V to pin 3 of the SSR, and goes out when that pin drops to zero.
When on, the fan gets around 14.9V of the supplied 15V
But when the SSR is off, the fan is still getting around 13.8V.
So I'm wondering:
a) is there a minimum load required on the output side for the SSR to operate?
or
b) am I completely misunderstanding how the SSR output should be wired and should it be 0V at pin 1 and 15V going through the fan back to pin 2? Don't want to try this without asking as I'm wary of shorting 0V to 15V...
Image of it in action:
And here's how my circuit is wired up:
The control is from an ESP32 (like an Arduino) and it supplies 0V for off and 3.3V for on.
The load is a computer fan, with 15V wired into the output part pin #1 of the SSR. 0V rails are shared across the fan and ESP32 circuits.
The SSR appears to visibly work as expected - the red LED comes on when I apply 3.3V to pin 3 of the SSR, and goes out when that pin drops to zero.
When on, the fan gets around 14.9V of the supplied 15V
But when the SSR is off, the fan is still getting around 13.8V.
So I'm wondering:
a) is there a minimum load required on the output side for the SSR to operate?
or
b) am I completely misunderstanding how the SSR output should be wired and should it be 0V at pin 1 and 15V going through the fan back to pin 2? Don't want to try this without asking as I'm wary of shorting 0V to 15V...