Q&A Forum
hey guys, i have a V5 DAQ, I've wired up a msd8918 and spark fun board as explained in a few posts. however i simply cant get the rpm to work!. I've tried on rpm input 1 & 2, measure voltage's to confirm they're what's required ect ect.
I'm not sure what I'm missing or doing wrong here, but would be amazing to have rpm working to determine wheel slip/converter slip.
thanks, Tyler.
If you connect the MSD to RPM2 then make sure to turn on the RPM2 gauge to see if it reads.
The Engine RPM gauge does not automatically display the actual Engine RPM, it depends on the settings. If you use RPM1 as your load cell RPM, and fixed gear ratio, then Engine RPM = RPM1 x Gear ratio. You can set it to automatically calculate the gear ratio by clicking the variable gear ratio option in the Gear ratio setup. In this case it will display the Engine RPM, but the relationship is still Engine RPM = RPM1 x Gear ratio. So this only works when the roller/brake turns (otherwise the gear ratio would be infinite). Therefore it is a good idea to turn on the gauge for the direct engine RPM measurement (RPM2). You can call RPM2 something else than RPM2, for example Direct Engine RPM (don't call it "Engine RPM", since this is a built in channel).
RPM1 and RPM2 are just looking at 0-5V square signals so if it does not read then there is no 0-5V signal.