As we're in the high riding season, I don't have much time to spend working on updating my Dyno to YourDyno.

I've decided to fit both the V5 instrumentation and brake power supply in the original Dyno electronics cabinet.

I've built a small aluminum holder to place the power supply just in from of the cabinet fan to ensure proper cooling. The V5 instrumentation is fitted at the bottom of the cabinet so that the base is free for DJ'a original power supply to feed a Zeitronix ZT-2 and ZT-3 combo I plan to use both as Oxygen sensor controllers and datalogger. This first question is about this.

Standard V5 Instrument kit, brake power supply and load cell ordered!

Can't wait to have it all set-up and working! 

Thank you both Marco and Jostein. Now it's crystal clear for me!!!

500kg is good.

Maybe that helps: https://www.dynojet.com/motorcycle-chassis-dynamometer-model-250i/

The Retarder is: Frenelsa model F16-120

I think the picture is now added!

The problem is that I haven't found any spec on the retarder, so I don't how to find out the max Nm spec for the retarder 

To be on the safe side, fitting a 500 or even 750 Kg load cell would be a safer option? I prefer not to worry about max braking if there's no adverse side effect when using a higher capacity load cell.

By the way, how can I attach pictures to my posts?

Hi,

The load cell should be placed 90 degrees to a line from the middle of the brake. The load arm (or more accurately, the line from the middle of the brake to the connection point of the load cell) does not need to be horizontal, although this is the most common. 

The normal way to calculate the correct load cell is Load cell size (kg) >= Max brake torque (Nm) / 9.81 / Torque arm length (m)

If the brake is never over say half the capacity then you can use half the capacity when calculating the load cell. But in that case you should limit the max voltage output of the power supply in the software to make sure there is no risk that the brake will go to higher load. 

You can measure the resistance of the brake to determine if it is 96V or 192V. 96V is around 5 Ohm while 192V is around 20 Ohm. You need 220-240VAC input to the YourDyno PS, and 192V is better than 96V (lower current, less noise).