mer
Member
Some might say this would would or might be a dum question but has anyone ever used a small 12/24 volt plc for a ignition system for a engine .......
But I agree - no way a PLC would be fast enough to do ignition. Figure a V8 engine at 3,000 RPM - that's energizing the coil 24K per second, or once every .04 milliseconds (do i have my decimal right? it's too late in the evening)
Even if you could get a PLC to scan that fast, which you can't, the timing - so many degreess off top dead center - probably wouldn't be anywhere near as accurate as need be.
If your serious about a PLC controlling this-
Look at the Siemens FM352-5 high speed boolean processor
http://www.automation.siemens.com/m...0/function-modules/FM352-5/Pages/Default.aspx
Most engines on ships, assuming they're not gas turbines or nukes, would be Diesel and wouldn't have an 'ignition' system anyway.
ok i admit it was a dum question i was just looking at a encoder that would operate at 9000 rpms then looked at at high speed counter that would operate at 5khz and thought that it would be possible but as far as keeping up a plc could read the info at high rpms its the outputs that are to slow correct??? ive had dumer ideas that lead to workables...