Q&A Forum

Notifications
Clear all

RPM Sensor

9 Posts
3 Users
0 Likes
1,342 Views
(@james-meyers)
Posts: 56
Member
Topic starter
 

I have a Go Power DA512 dyno that I am going to be putting YourDyno on for instrumentation.  My only question is with the RPM signal.  The GoPower dyno has a sensor in the rear of it for speed that sends out 7 volts/1k rpm.  Is there a way to use this with this instrumentation using a voltage divider or something along those lines?  

Or do I need to figure out how to make a tone wheel to use a different speed sensor?

Thanks in advance.

 
Posted : 30/04/2020 2:42 pm
 dave
(@dave)
Posts: 7
Member Customer
 

Hi James

I have just acquired a Go Power DA312 which I'm thinking of adding a YourDyno system to.  Mine has a mechanical rev counter. I have made a toothed wheel which is fitted to the input flange of the dyno.

I would like to keep the control panel and gauges which are fitted to the dyno if possible. As the load cells are hydraulic and need quite a lot of movement I have fitted a 3 wire 0-5 volt brake pressure transducer to the fluid lines which I hope to use as the load cell to the YourDyno box.

Not sure if it will work yet but cant see a reason it wouldn't.    

Maybe someone could put me right. I will be interested in how you get on.

Have you got the water flow sorted? I'm going to use a large tank and pump and recirculate the water after cooling it.

Good luck

Dave

 
Posted : 04/05/2020 10:44 pm
(@admin)
Posts: 1397
Member Admin
 

Toothed wheel and a hall effect sensor is the way to go. Alternatively an encoder. 

@dave, the best is to use an electronic load cell. The electronics are made for that. You can read a 0-5V signal using an Aux channel, but this is far from as accurate as a load cell. Also, corrections for environmental conditions, etc work on the torque that the load cell reads. 

If you want to use the pressure to read power, it is better with a pressure sensor that is electrically of the same construction as a load cell; using a Wheatstone bridge. These have 0V and 5V power inputs and 2 signal outputs. This can be connected to the normal load cell input of YourDyno and used as a load cell. I have never tried it, but it should work if you find a suitable sensor.  

 
Posted : 04/05/2020 11:57 pm
 dave
(@dave)
Posts: 7
Member Customer
 

Hi

Thanks for the advice. I will fit a proper load cell when I have finished the rebuild.

James, please share your experiances with your upgrade. You may stop me making more mistakes.

Thank you.

Dave

 
Posted : 05/05/2020 7:29 am
(@james-meyers)
Posts: 56
Member
Topic starter
 

This is all the farther I have gotten.  Still need to make a shaft to hold my speed pickup wheel then I should be ready to go.

https://www.youtube.com/watch?v=gXS2ehSDi0w

 
Posted : 29/07/2020 1:59 pm
(@admin)
Posts: 1397
Member Admin
 

Cool!!

 
Posted : 29/07/2020 2:49 pm
(@james-meyers)
Posts: 56
Member
Topic starter
 

Well I finally got everything working as it should.  The numbers repeat within 1hp so I'm really happy about that.

I do need to change the stepper motor to something with more power, when the water pump is turned all the way up the stepper won't close the valve due to the water pressure.

Also going to change the valve disc inside the globe valve.  Right now it is just a flat rubber disc and doesn't always close off all the way.  Planning on making a tapered valve so that the flow is a little more linear to give better control.

Video of one of the good runs:  https://youtu.be/_LjBII3F67M  

 
Posted : 09/02/2021 4:27 pm
(@admin)
Posts: 1397
Member Admin
 

Cool! Very nice to see it in action. You can see on the gauge that the brake controller is having a work out 🙂 

Are you running Load Control?

 
Posted : 10/02/2021 7:28 pm
(@james-meyers)
Posts: 56
Member
Topic starter
 

@admin I have used Load Control and Power Sweep.  When in Load Control the sweep rate ends up being half of what I have it set to.  It's smooth but doesn't match what I have set.

In Power Sweep it is also smooth but the acceleration rate of the sweep matches exactly what I have it set to.  The video I posted was using Power Sweep if I remember correctly.

When I overlay two runs from the two control modes they match perfectly, so I will probably keep using Power Sweep for now until it doesn't hold steady.

And good catch on the brake controller percentage.  I am hoping the changes to my water valve smooth that out a little bit.  My only concern is that the way the water enters the valve I think I am going to need a larger stepper motor to control it.  Right now it's borderline having enough torque to close the valve.  

 
Posted : 10/02/2021 8:26 pm
Share:
Select your currency