When yourdyno is reading rpm for power sweep which signal does it use when making its calculations? I have hooked up the rpm signal through my spark plug lead which works great , but is this the rpm it’s using or does it still relay on the roller for its calculations? 
thanks heaps 

The problem I’m having is when I do a power run it holds the brake on at about 5k rpm and won’t let the car rev higher than that unless I wait . It seems like it’s loading way to much ? It then gives me a ridiculous high hp reading . I have a eddy current brake and it’s set to analog output brake 0-5v . Any help will be great 

@bernard-makhraz, yes you need an RPM sensor on the rollers/brake. See https://yourdyno.com/YourDynoHelp/brake-rpm-sensors/

So the engine RPM sensor, if you have one, is only there to set the gear ratio. Brakes are controlled via the sensor at the brakes, using the gear ratio to calculate the corresponding engine RPM. 

For an eddy brake, Power sweep is a good option. You set the Start RPM, End RPM and RPM change rate. You can also set a wait period before the sweep starts. If you want it less then just decrease the number of seconds. 

The latest version includes a ramp-up functionality where the brake is smoothly increased to a set value as you get near the start RPM, then the PID takes over. With this, skipping the wait period completely is also possible. Download here: https://yourdyno.com/YourDynoInstaller_3.2.83.exe

Let us know if you still have issues!

@admin hi yes I do have a sensor on the rollers but does your dyno only use that for calculations or does it use the spark plug lead attachment also for this ? 

@bernard-makhraz, it uses only the roller RPM sensor. Engine RPM (from spark plug lead, OBD, etc) is just for gear ratio calculation. 

@admin ok cool , what ramp rate is a norm for a engine approx 600-700hp ? 

@admin hi gave it a try today and got it to work very well 👌only thing I couldn’t get the new version to work . It downloaded fine but the new features didn’t show up .

thanks again 

@bernard-makhraz, good to hear. 

For the ramp rate, it is up to you. I like to for example 250 RPM/sec.

You find the new feature in the attach pic.

I have also some trouble with power sweep. Using hub dyno, two Telma CC160.
I think that low inertia is the cause of the problems, and tried to adjust pid settings many hours but not getting the result that i want to.

If i WOT and power sweep starts automatic, rpm rises up to ~4500rpm altough i set it to 2000rpm. I have to keep 5-10sec delay or ease throttle to achvieve steady 2000rpm. The power sweep starts quite good after 2000rpm delay but when the boost hits on, rpm little escapes and makes the graph looking odd. Sometimes there is some pirouettees on the graph...

Should i use RPM curve or what i do wrong? Manual brake works well, there is also some delays to achieve set rpm but its not that bad.

Hi,

With PID you should use the brake ramp up function to remove the overshoot. 

You can also use the Load Control. This is a good brake mode if you have a very sudden boost. Brake ramp is built in for Load Control, so set Brake ramp up to 0 in that mode.