|
Les,
My basic understanding of generators (happy to be corrected by those with better knowledge of technical terms, etc):
The cheaper generators have a petrol motor connected directly to a generator that makes the AC power. That petrol motor must run at 3000rpm to produce 50Hz AC power. This is inefficient if you are using a large generator, eg >1kVA generator, but only drawing a small load (most astro setups would draw <0.5kVA (~500 watts). If you switch on a big load, the petrol motor takes a finite amount of time to ramp up it's output, so the voltage and frequency can vary - ie, the AC power is dirty. Because the motor is running at high speed all the time, they are usually noisy.
The expensive (eg Honda) generators use an inverter. The petrol motor turns a generator that produces DC power. This DC power is fed through an inverter to produce high quality, clean AC power. They are more efficient as the petrol motor can run slower and produce just enough power to meet your requirements. If you switch on a big load, the inverter can maintain a stable voltage and frequency of AC power (better than the cheaper generators) while the motor speeds up (not sure how ? capacitors??).
That's my understanding. I don't own a generator as I don't have need for one - fortunately all my observing sites have 240V. I'd definitely buy a Honda Inverter or equivalent if I needed one.
DT
|