I have purchased a older Maha Chassis Dynaometer previously used by a emissions testing shop. It has a 150 horsepower eddy current brake and a 2000 pound flywheel. I’d like to upgrade the eddy brake someday so I can hold at set rpm’s for tuning but for now the heavy flywheel allows me to dyno larger hp motors just doing inertia pulls. I started by gutting the electronic control cabinet. I purchased a YourDyno instrumentation kit and built a control for the eddy brake using a bridge rectifier and IGBT. I replaced the analog roller rpm sensor with a digital one and re machined the trigger wheel so it had 18 teeth. I added a external 12 volt power supply for the wideband and other optional sensors. To keep things tidy and the box connections from getting damaged I placed Aviation Plug Connectors and a panel mount micro usb male to type B 2.0 Female Extension in the cabinet cover. I chose the usb type B for the cover because it is a little more robust connection. I for engine rpm’s I have Bluetooth obd or a wired input using a dc-dc solidstate relay as a opto-isolator.
Link to Photo’s and brake control schematic Retro fit files