Latched Relay with Current Protection

151

02:10:42

the start and stop buttons control the latch state.  the comparator is a current sense that switches on and pulls the latch down to switch it off when current gets too high.  

start button holds the latch on without oscillating, which I hope will allow very low resistance startup loads eg. motors to start up and achieve their lower running current before the start button is released. 

all bench machines have separate start and stop push buttons

published 10 years ago

flowDAQ

10 years ago

I would hold that start down until there was smoke😈

faceblast

10 years ago

yeah I should turn it into a monostable

2ctiby

10 years ago

I've been been holding off doing a little circuit board stuff for a while now 'cause I wanted a sharp latch. This looks really good for me. Is there a down side...what's this 'smoke' concern?

flowDAQ

10 years ago

If the rotor is locked for some reason (board in saw) when it starts, then holding the start to long can cause the windings to heat up and smoke. But frankly if an operator does that they should not be allowed to run equipment. I say make your board, this looks solid.

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