AndyUK's Build - 1.2x1.0m Gantry

[Kitwn]

Likely a TLP185 or equivalent. CTR = 100-400%. Your measured voltage is fine and indicates the behaviour should be as you expected. Disregard all my random ramblings about optos.

As someone who likes to design and build the odd circuit of his own, I have found your 'ramblings' extremely informative.