load, then what will be the effect on lifting the load at high speed, RPM of electric motor, and any other answer which anyone can give me for my clearification.
For a start you would not have any control over the lift. Electric chain hoists lift normally at about 2 metres per minute, especially at high loads. This is so that you are in control the whole time. If you lift at high speed with 8 ton, I hope that you are standing far away!!!! The motor may be 30000 RPM, but the gearbox would have to be huge to transmit the torque from the input to output and would not be really feasible. Stick to normal motors that run about 3600 RPM, geared down to slow lift speed as above and you should be safe....
Most electric chain hoists are rated for fairly slow RPMs to keep things on the safe side for the operator and the chain hoist itself. They also have load brakes basically for this reason. The sort of speed you seem to need could mean unsafe operation
you would need a much more powerful motor. If the previous motor was 1 HP running at 1000 RPM, the new one would have to be 30 HP to spin 30 times as fast with the same load. And the load would move much faster, and the risk of an accident would increase. .
You need to set up some high gearing to convert your 70-100 rpm pedal cadence into 1200+ rpm at the alternator. One way may be to put a belt around the rear wheel and around a pulley on the generator. Lot's of ideas on Google ... see the link
well, one of 3 things would happen. 1. you'd spend lots of money getting the gearing ratio right, or 2. the gearing would be so high that the motor wouldn't have enough torque to move the hoist, or 3. whatever you're lifting would make it up past the level of the roof, still maintaining a fair bit of speed -- and you'd be looking for something really safe to hide under.
