RPM and Frequency Adjustment
Updated
by
Juan Velez
This covers the following Champion Power Equipment models: 79cc - 439cc Engine Powered Generators.
Read instructions carefully and completely before performing service.
SAFETY PRECAUTIONS
- To reduce the risk of injury, user must read and understand the operator’s manual before using this product.
- DO NOT make any adjustments to the generator without first stopping the engine.
- Burns from hot parts — let the engine cool completely before touching hot parts.
- Injury from moving parts
- To reduce the possibility of fire or explosion, be careful when working around gasoline. Keep cigarettes, sparks and flames away from all fuel‐related parts.
- The adjustment for the RPM (engine speed) and Frequency (Hz - Hertz or Cycle ) are directly related. Our proper engine speed is between 3600 RPM and 3720 RPM in order to maintain the best frequency setting for your appliances that have timing devices internally. A perfect frequency would be 60 Hz or cycles, and it is what our utility distribution is designed to deliver through the power grid. When using a generator, it is nearly impossible to guarantee an accurate 60 Hz delivery due to different engine speeds that can be caused by a variety of items, for instance, a plugged air filter might change the engines ability to run at 3600 RPM or poor fuel delivery taking power from the engine. When setting the Hz to the optimum setting, the best way is to use a tachometer for small engines and set the governor throttle adjustment screw to a minimum of 3600 RPM, or better yet, a Hz meter which is usually found on the most mid to high-end multimeters. Note: The governor throttle adjustment screw can be identified with yellow marking paint and a spring around the screw threads to keep it from changing adjustment.
- Using the Hz meter, you can adjust the governor throttle screw to raise or lower the engine speed to get an maximized setting of 60-62 Hz. You may want to load your generator with the most common load you will be using and then adjust the screw to give you an adjustment within the 60-62 range. If you set it too high, then it means you are running the engine faster than need be, and it will add premature or serious engine damage to internal parts. It is mechanically governed to maintain a proper engine speed once it has the standard setting in place. Do not attempt to adjust this governor throttle adjustment screw without the proper tools available. DO NOT CONDUCT THIS BY EAR. If you do not have a Hz meter or tachometer with you, then use a conventional electric clock with a sweep hand for seconds. If you plug the clock into the generator, a proper engine speed would make the clock do a minute in exactly 60 seconds against any other timing device. If the clock takes longer to do a timed minute, then the engine speed is too slow and you need to raise the engine speed by turning the governor throttle screw clockwise. On the other hand, if your clock does a minute less than a normal clock should, then turn the governor throttle screw counter-clockwise. Now you should have a good setting for your generator's frequency setting. It is best to do a frequency setting before doing any voltage adjustment.
- Refer to our voltage adjustment technical bulletin for proper adjustment procedures.
View and download the PDF version here.
