Q&A Forum
Having issues with getting a clean rpm signal. This is on a water brake engine dyno. The engine I am trying to test is a GM 350 with an HEI distributor.
I bought this opto coupler: https://www.amazon.com/gp/product/B07YJL3MQQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Then wired it like outlined in the wiki page across the positive and negative coil wires.
When I go to run a test from 2500rpm to 4000rpm it starts the test, begins to load the engine then says done well before getting to 4k rpm. When I take a video of the screen you can see some spikes in rpm which goes over 4k and that's why it's ending the test.
My question is why? Is there a different opto coupler I need to use?
Thanks in advance. This is the last thing I need to figure out in order to make some actual power runs!!!
I left it on the dyno frame and rubber mounted it. With no rubber mounting it was causing interference.
@james-meyers Hi, I have a similar problem and would like to know if you removed the Yourdyno box from the dyno chassis? Or did you fix it more securely so there would be a good earth to the box? thanks
Well I am pretty sure I figured out what my issue was. It wasn't the speed sensor or trigger wheel at all, even after trying multiple setups. I had the YourDyno.com data acquisition boxed mounted to the top of my wiring box on the dyno. I had mounted it quickly with a couple of self tapping screws. this appears to cause some interference which was causing the erratic speed reading. So a bunch of wasted time and money on my part but I sure did learn something, lol.
Now to thaw out the water tanks and do some testing to see how well this whole setup works!!
@james-meyers, I meant you go to Options->Backup options to file, plus in Options->Raw data logging, you enable the raw data logging. It will provide a .log file in the "session" folder for each run that you can send me.
2 teeth is very low, you should have more teeth. Looks easy to fit a trigger wheel there!
@james-meyers, a few things to sort out there. Send me the saved options and a raw log file and I will take a look.
Pretty much does the exact same thing. The log is attached. These two runs were supposed to go to 4k rpm.
@admin That is the process I was following. It doesn't let me manually choose the file, only the folder that it is in. But it still says that it cant find the file in the folder.
Let me know if there is anything else that I should try. Or let me know when you could remote in. Thanks again
OK, yes for Win7 you need a driver. Here are the instructions:
USB Driver:
Windows 10 installs the driver automatically. For Windows 7 and Windows 8 you need to manually install the driver.
To install the driver for Windows 7 and 8: Plug the YourDyno box into the computer, Open Device Manager, find “Ports (COM & LPT)”. You should see an entry there called USB Serial port or Cypress USBSer or similar. Right-click and choose “Update driver software”. Choose the .inf file you download here: Download driver.
The driver you download is a .zip file that you need to unzip to a location (it will be an .inf file), then choose it when updating as explained above.
If you are still struggling I can log in remotely and get it going.
@admin Yes the USB Driver using Windows 7 is what I am trying to do. However, it went through the first part of updating the driver and now shows that the YourDyno box is not connected at all times and won't find the new driver that I have downloaded.
I went and got my hotspot from work and tried to update the firmware online but again with no USB driver installed it won't connect to the YourDyno box. Below is what the status shows when trying to update the firmware online and also the message I get when trying to update the USB Driver.
Any help would be appreciated. Seems that I currently have an $800 paper weight to stare at. Thanks