PWM and Duty Cycle Clarification

Having problems ? let us know the details here
Post Reply
Posts: 1
Joined: Thu May 23, 2024 4:53 am

PWM and Duty Cycle Clarification

Post by rjmlondon »

I am seeking some clarification on a PWM scoped signal and the duty cycle interpretation that i captured.
Its taken from a Alternator GENMON and GENCOM signals on a 2014 Ford Mustang GT.
Both signals are ground switched PWM. I have attached the file.
I am using a Pico scope 2204a.

My question is does the Pico scope measure the high portion of the waveform as the ON time even though it is ground side switched?

This makes the difference if I'm looking at a 75% duty cycle or 25% duty cycle.

NB - The capture was taken at Idle but loaded with the AC, Lights and Radio on.

Any insight would help.
new alt loaded 170524.psdata
(141.16 KiB) Downloaded 58 times

Site Admin
Site Admin
Posts: 4552
Joined: Fri Jun 10, 2011 8:15 am
Location: St. Neots

Re: PWM and Duty Cycle Clarification

Post by Martyn »

If you are using PicoScope 7 software then we offer Negative and Positive Duty Cycle measurements and maths channels, so you can chose which one you want to use.
Technical Support Manager

Post Reply