3000W Chinese Gensets Info.

Wrace wrote:

TomG2 wrote:
Wrace. Have you done any more testing with the Spp6 capacitor. I am sure there are many of us hoping that it performs as well as expected.

No, just what I have documented on this thread already.

I tried the Spp6 wired across the the factory start capacitor and across the run capacitor and in both cases it made the situation worse over the stock AC. With the SPP6 installed in either position the champion would start the AC with some increased effort and the Honda didn't even come close to starting the AC.

The complexity of induction motor design is way, way too much to try and explain on this thread. In fact, I rely on looking up specific motor data when needed.

Many electric induction motors use capacitors only to start, others us them to run as well by creating a differential between current and voltage. Some even use the same capacitor for both.

"Normally" refrigeration compressor motors use a high value capacitor to give the motor an extra surge of current to get it rolling in the right direction and to overcome locked rotor current surges. Frequently adding additional capacitance - such as the Supco unit - can be beneficial with hard to start motors - particularly those that use thermal disk overload protectors that heat when rotor current on start-up is high and is prone to cutting off the compressor before it gets rolling.

But - and there is always a "but" - additional capacitance is not a cure-all like aspirin is for humans. Some electric motors simply do not respond to added capacitance. In fact, the additional capacitance can hurt the motor performance by changing the voltage/current curve the motor is designed to respond to.

You know, Mr. Wizard is the electric motor man on this thread. I do not pretend that electric motors are items I am an expert on as far as design and service. I do remember back in the 70's a class on induction motors when I was working on my BA in EE'ing - but that has been decades ago!