@jpnovak  i have a qwestion im looking for the original interface of a maha 850 dyno for motor cycles  i have the lps 2000 steering box   do you have the original interface ? Greets john

The Dyno is up and ready to run. 

the torque load cell was calibrated using a dumb bell weight hanging on a steel beam.  I used 2 C-clamps to hold it to the top of the fixed section of the eddy brake.  the beam made contact with the vertical center, was leveled in a tangent line.   The clamps were placed one on each side of the center line leaving a net zero load.   The measurements and spreadsheet made the process straightforward.   I applied the torque load in the rotation direction.   I get reasonable numbers when pushing on the beam and watching the torque readout in the software.  

The speed sensor is verified working.   I tried a bicycle but could not get it moving.  So I rolled with my feet in a "log rolling" style.   

the only thing I have not verified is the RPM sensor.   I will connect that once I have a vehicle strapped down and ready to test.  

Planning to move the dyno to a friends shop for the next phase.  

I 

Progress.   

• Ramp install is solved but not implemented.  
• Speed sensor and new trigger wheel mounted.  
  • I drilled and tapped the outer perimeter of the existing trigger wheel and bolted the Yourdyno wheel directly do it.   
  • I also removed the existing VR sensor,  drilled out the mounting hole for the Yourdyno speed sensor, repositioned the bracket by brute force (bent) and installed the sensor in newly drilled hole.   It is now centered and normal (perpendicular) to the trigger wheel.  

I understand the calibration process for the load cell.  I have a design in mind for the load beam to hang weights.    But,  Do I apply my load to the torque cell in the same or opposite direction as the rotation?  The rotation direction results in a "pulling" upward motion on the strain gauge.   I assume I want the calibration load in the same direction.   

Second.   How do I get or calculate the MOI for the flyweel?  Can I use dimensions and steel density to get close enough?  Appreciate any help here.   

Thanks for all the support so far.  Pending calibration I can have the dyno running by next week.   

jamie

And the PC showed Status Ready.    Now I need to figure out how to calibrate the torque sensor.

Tomorrow I will fab a new sensor mount for the toothed speed wheel.   And also fab my ramp mounts.     I am going to reuse the same ramps from my trailer since I know they are long enough and high enough load rating for most planned test and tune sessions.     

Once I had power cable ready I plugged it in.   DC source was showing power Status green LED and no errors.    That's a good sign.  

Today was focused on. Main power.     I wired a disconnect box into a 21' (7m) power cable.   This will give me lots of freedom to move around the shop floor.     

Hi,

Yes, you are right, the existing trigger wheel only works with a VR sensor. 

You can mount the trigger wheel on the brake roller or on the brake itself. You cannot mount it on the roller axle without a brake. This is because the rollers may have slightly different speed due to tire compression towards the front (brake) roller. 

You don't need to worry about cooling air to the brake power supply. 

Jostein,

Can you clarify your statement about the speed sensor mounting.     Best to mount to retarder or wheel rollers?    Existing speed sensor is mounted to wheel rollers.   I have to see if I can. Get access to mount to retarder axle inside chassis without pulling it out.     

I was able drill some hardware and pull end cover.   

For reference the tooth count is 100.    

Now I have to decide if a VR to 5V converter board is easier than mounting the toothed wheel and Hall Effect sensor I bought with my Yourdyno setup.   Traveling all week for work so lots of time to think.

Thank you for clarification.   I might have downloaded older manual.   I did not see engRPM in manual.   But it is on the control box.   I want RPM for engine speed lock relative to EFI column for load cell tuning.

Can someone verify the tooth count for Maha speed sensor?   I think this is 120 tooth. 

I cant get the access panel off to count.     There seems to.be problems where someone in the dynos past life used Standard hex keys instead if metric.   Most of the hardware is stripped.    I just have not had time to pull amd replace.    

The DC supply and control box are now wired.    

I cut an access panel in the electrical box lid so the fins of the supply stick through.    Also planning a cooling fan at the top to pull air across the compartment.     

The eddy current coils are now wired 4 in series.    I measured 45Ohm nominal across each one.    

@jpnovak yes, manual control is often the best for things that anyway are manual. No need to run it through the software.

The Innovate clamp connects to EngRPM (not RPM2). 

Yes, the thermocouples are K-type (isolated).

Cheers

Thank you for the response.   

Related to the cooling fan.  I meant use an I/O pin to drive a relay and then setup temperature control to trigger relay.   I have since reconsidered.  It is easier for me to wire a 220Vac fan to the input and just have it always blowing air when the dyno is powered up.   

I am also swapping the center lift bar gas solenoid to a 22oVac so that I an add an external switch on the outside panel for load/unload.   Easier to have manual control than software control.   Especially considering it will be manual to strap the car down.   

Thank you for the suggestion on the Innovate Motorsports RPM pickup.   I use their WBO2 sensors in most of my EFI installs.   I will plan to wire that to RPM2 inputs.   

I am using RPM1 input for the wheel speed sensor (roller speed) that is existing on the dyno.   i have to verify the tooth count.  

Are the ThC inputs for Thermocouples or Thermistors?  if Tc - what type?  k-type?  

Also, for reference.   Jostein answered a question I had posted on the DIY Dyno FB group.   The current retarder has 4 coils is wired 2S2P.   He suggested that I wire all 4 coils in series (4S) and the drive them with 192V output on the DC supply.   I have already connected the coils.   

Thanks for all the help.  I hope to have most of it wired tomorrow so I can power it up for the first time.   then I have to figure out how to calibrate the load cell.   Until next time...