LED light for driver output visualization?
LED light for driver output visualization?
(OP)
My company has nitrogen dosing units. A PLC sends an output to a driver that sends power to a coil. The driver also pulls current away from the coil after a given time duration to allow the coil to close the valve quickly.
We are able to see the 6 millisecond output signal from the PLC to the driver via an analog output wired to our high speed camera LCD display. We want to see whats is going on with the voltage and current going to the coil from the driver, but the voltage is too much for our signal box (converts the signal to something the camera can see). Is there an LED light that can withstand 170 volts for 4 ms and then 22 volts for the remaining 2 ms? I want to wire it in paralell so we could see it light up on the high speed to see if the coil is getting what it should be getting.
or maybe there is an inexpensive oscilloscope that has an analog output? Any help is appreciated.
We are able to see the 6 millisecond output signal from the PLC to the driver via an analog output wired to our high speed camera LCD display. We want to see whats is going on with the voltage and current going to the coil from the driver, but the voltage is too much for our signal box (converts the signal to something the camera can see). Is there an LED light that can withstand 170 volts for 4 ms and then 22 volts for the remaining 2 ms? I want to wire it in paralell so we could see it light up on the high speed to see if the coil is getting what it should be getting.
or maybe there is an inexpensive oscilloscope that has an analog output? Any help is appreciated.





RE: LED light for driver output visualization?
-handleman, CSWP (The new, easy test)
RE: LED light for driver output visualization?
RE: LED light for driver output visualization?
-handleman, CSWP (The new, easy test)
RE: LED light for driver output visualization?
Don
Kansas City
RE: LED light for driver output visualization?
http://led.linear1.org/1led.wiz
RE: LED light for driver output visualization?
I think you need to use a different tool, like an oscilliscope.
RE: LED light for driver output visualization?
Have you calculated how long it will take the current in the coil to rise when you first apply power? Thisis one area where a scope looking at the current draw could be really valuable.
Didn't get what you're planning to do with an analog output from your desired cheap scope.
A.
RE: LED light for driver output visualization?
RE: LED light for driver output visualization?
If you try an LED and associated resistors, it would be a sensible precaution to wire another diode in parallel with your LED, but pointing the other way.
In circuits with coils, there's always a risk of getting some reverse voltage. As designed, the chain of resistors reduces the voltage at the LED to a safe level provided there's current being drawn through them. If the voltage is the other way round, the LED won't conduct, so there's there's no current through (and hence no voltage drop across) the resistors and all the available volts appear across the diode junction. Mere ohnoseconds later, the LED becomes a smoke emitting diode.
The safety diode doesn't have to be anything clever. You might choose another LED (different colour might look nice on your high speed movie)
A.