Heenan & Froude G_series Hydraulic water brake engine dynamometer  manual pictures of internals of the dyno

Heenan & Froude G_series Hydraulic water brake engine dynamometer  manual pictures of internals of the dyno

Heenan & Froude G_series Hydraulic water brake engine dynamometer  manual pictures of internals of the dyno

This paragraph should of read in the very first post should of read as follows - ( wouldn't allow me to edit the first post )

Once I have made the measurements and calculations for the right size " Load Cell Rating " to fit neatly within my dyno covers/body constraints and parameters area i have to play with OR  I'II need to fabricate another existing torque arm to work in unison with the gauge torque arm ( spring balance ) of my Heenan & Froude GB4 engine dyno , I'II be placing a order with Jostein_Fonneland@YourDyno for " YourDyno instrumentation kit "

Hi,

It will be interesting to see how your project goes! Can you post a picture of where you plan to place the load cell? 

To run YourDyno and the original instrumentation in parallel you need to make sure YourDyno's load cell is in series with the original torque measuring device, such that both measuring systems see the full load. 

Also, make sure you have a way to calibrate the load cell in the setup with a known weight. 

Hi , space in the clockwise rotation and to compress the S-type load cell is very limited to couple up but on the flip side (opposite of compression) can a S-type load cell  be used accurately in expansion mode ? as I have more room on the opposite side of the dyno to couple up within the area constraint and still utilize the original analog gauges with little or no  modification to the dyno body.

Also, make sure you have a way to calibrate the load cell in the setup with a known weight. 

My H&F GB4 engine Dyno has certified calibration weights which I use all the time for running purposes and calibration. Also have additional weights

Hi,

The load cell works equally well in compression and expansion mode. The calibration takes care of the orientation.

Cheers,
Jostein

OK , been busy at work and hopefully will catch up and back on the dynamometer over the weekend.

Toying with the numbers between 300mm and 500mm long load cell torque arm length. Measurements ain't yet 100% confirmed the covers will fit back on. Will require a few trial dummy fits to see the space constraints.

This dyno is capable of 1,000 BHp and 10,000 RPM short period testing , so from the calculation below one can see a trend as far how calculating the right load cell size selection to use on my dyno. Fingers crossed i get some work done on the dyno this weekend.

My main engines I test are around 450BHp upto 700Bhp between 5500 RPM up to 8,000 RPM and occasionally see some extremely high output engines.

Torque arm length 300mm,400mm,500mm at MAXIMUM working BHp and RPM of the dyno.

Engine horsepower = 1000 , Brake RPM @ max power = 9000 , Torque arm length (mm) = 300 , Load cell rating = 265.44 kg

Engine horsepower = 1000 , Brake RPM @ max power = 9000 , Torque arm length (mm) = 400 , Load cell rating = 199.08 kg

Engine horsepower = 1000 , Brake RPM @ max power = 9000 , Torque arm length (mm) = 500 , Load cell rating = 159.26 kg

Torque arm length 300mm,400mm,500mm at General Engines I Work_on are BHp and RPM

Engine horsepower = 700 , Brake RPM @ max power = 8000 , Torque arm length (mm) = 300 , Load cell rating = 209.03 kg

Engine horsepower = 700 , Brake RPM @ max power = 8000 , Torque arm length (mm) = 400 , Load cell rating = 156.77 kg

Engine horsepower = 700 , Brake RPM @ max power = 8000 , Torque arm length (mm) = 400 , Load cell rating = 125.42 kg

Attached is a pictures of my working and calibration weights , red weights are  10 LBs ( 4.54 kg) , black weights are 5 LBs ( 2.26 kg) and the linkage hook weighs 1 LBs ( 0.46 kg).

Correction made

Engine horsepower = 700 , Brake RPM @ max power = 8000 , Torque arm length (mm) = 500 , Load cell rating = 125.42 kg

Hi, since you have many engines to test and various RPMs, it may be easier to calculate from the max Torque your brake can take. From there it is easy to calculate the load cell size. It is independent of RPM.

Load cell size = Max torque brake (Nm) / (load arm length(m) * 9.8(N/kg))

Posted by: admin

Hi, since you have many engines to test and various RPMs, it may be easier to calculate from the max Torque your brake can take. From there it is easy to calculate the load cell size. It is independent of RPM.

Load cell size = Max torque brake (Nm) / (load arm length(m) * 9.8(N/kg))

Hi Jostein , Understand where you are going with this but it all still falls back onto the " load arm length(m) " . The load arm length is the issue for it to fit inside the dyno enclosure and over head covers to retain the standard unaltered look and still use the standard gauges.

I'm looking at around 250kg to 300kg load cell BUT I might still need up to three load cells in total to a fix length torque arm to cater for smaller and great horsepower engines. As testing requirements change and just go into the YourDyno software part and make the necessary adjustments for testing purposes.

Or , If possible save YourDyno software in three different ranges and just swap_out the load cells as need and calibrate check and click the right YourDyno window. Just toying with ideas.

I'm Hoping by the start or middle of next week to place this order with you Jostein.

Cheers ( From Australia ) , PS: How is the stepper_motor testing coming along?

Hi, you should choose a load cell to cater for the max torque your brake will ever see. No problem to test engines with much less power, it will still be ok. If you test very, very low horsepower engines with the same setup as very large engines (let's say testing an engine with 10 times less horsepower), then yes, you will see a noise component due to the load cell being much too large. But even then it is small and very likely smaller than the mechanical noise component that is always present.

Check out this video showing the sensitivity of the instrument. It is set up to test up to 330Nm, and just a tiny touch from my finger shows up very clearly.  https://www.youtube.com/watch?v=mEHJjJzAn9s

I would advise to go with a large load cell now, you can always order an additional small one later for testing very small engines if you need. 

I have received the stepper motor and amplifier. I have a new software version just about to be released with much improved gauge setups among other things. After this is released, next up is the stepper functionality!

Cheers, Jostein

Hi , unfortunately the H&F G series engine dynos  when running four cylinder engines  you have to run the other end of the dyno for smaller engines and BHp . This involves a full 180 degree rotation of the  whole dyno unit hence the second load cell requirement. They have a A and B rotation and double flanges where the rest of the dyno is symmetrical for connecting all the plumbing up to. Not a pretty exercise to perform. So better of scaling the second load cell to suit the other side for more sensitivity range wise. I'm fully aware just a very light finger touch on the load cell triggers a response , done that 15 years ago on my chassis dyno. 

I see. Sounds like you need two load cells then!