I searched the forums and Google but didn't find any hits.
I'm trying to set up a control circuit for a 240v woodshop dust collector using a SSR and a simple 12vdc control circuit run from each blast gate. The dust collector uses a 2-wire 240v circuit (hot-hot-ground). As a proof of concept, I built a test unit using a 120vac light bulb and a 12vdc control. Everything worked fine at 120v, so I scaled up to the 240v dust collector (9A rated motor and a 25A rated SSR). It functioned correctly and the load side of the relay closed when the DC control voltage was applied, the dust collector started and everything worked fine. Unfortunately, the load side of relay failed to re-open when the DC control voltage was removed. Further testing showed that the relay had failed closed.
So... Is there something about a 2-wire 240v circuit that wouldn't play nice with a SSR or did I maybe just get a lemon (Chinese made...)?
The SSR that I used was rated for; 25A, 24-380vac load side, 3-32vdc control side
Thanks
I'm trying to set up a control circuit for a 240v woodshop dust collector using a SSR and a simple 12vdc control circuit run from each blast gate. The dust collector uses a 2-wire 240v circuit (hot-hot-ground). As a proof of concept, I built a test unit using a 120vac light bulb and a 12vdc control. Everything worked fine at 120v, so I scaled up to the 240v dust collector (9A rated motor and a 25A rated SSR). It functioned correctly and the load side of the relay closed when the DC control voltage was applied, the dust collector started and everything worked fine. Unfortunately, the load side of relay failed to re-open when the DC control voltage was removed. Further testing showed that the relay had failed closed.
So... Is there something about a 2-wire 240v circuit that wouldn't play nice with a SSR or did I maybe just get a lemon (Chinese made...)?
The SSR that I used was rated for; 25A, 24-380vac load side, 3-32vdc control side
Thanks