Damage running generator with no load?

[spendlove]

We just got another dual fuel generator and I was reading through the instructions. It said damage could result if you run it with no load. Can someone explain why this is the case?

Thank you.

 

[Hedges]

It is said to be carbon buildup, various effects on ring sealing, etc.

A bit of no-load is OK, but apparently best to run at moderate load or shut off, not keep running for light load.

Dangers of Running a Generator on Low Load or No Load | CP

Generators are at the forefront of power protection equipment. We explore the dangers of running a generator on low load or no load.

www.criticalpowersupplies.co.uk

https://www.cat.com/en_IN/by-industry/electric-power/Articles/White-papers/the-impact-of-generator-set-underloading.html

 

[Delmar]

Low loading definitely applies to a diesel engines with compression ignition. If they don’t make heat, they will not burn the fuel completely.

I have no knowledge of a problem with gas engines. Need to research for my planned backup system that needs to be oversized to start the AC compressor, otherwise will run under low loading.

 

[Hedges]

Low loading definitely applies to a diesel engines with compression ignition. If they don’t make heat, they will not burn the fuel completely.

I have no knowledge of a problem with gas engines. Need to research for my planned backup system that needs to be oversized to start the AC compressor, otherwise will run under low loading.

The Caterpillar link I provide above does describe problems with gas engines.
But we know car engines are designed to idle in traffic, and to operate around 10 to 20 HP while having peak 100 to 300 HP.

Is this with or without battery & inverter?
If an inverter can start the A/C, then generator only needs to supply running power, not starting.

Could a generator be rigged up with a very heavy rotating mass, to provide surge?
My HF chipper has a large, heavy steel disc. Very different feel when rope starting vs. most power tools.
When chipping 2" branches, that flywheel is what does it. If allowed to suck in the branch it does so too fast and slows to a stop after a number of turns.

 

[Delmar]

The Caterpillar link I provide above does describe problems with gas engines.
But we know car engines are designed to idle in traffic, and to operate around 10 to 20 HP while having peak 100 to 300 HP.

Is this with or without battery & inverter?
If an inverter can start the A/C, then generator only needs to supply running power, not starting.

Could a generator be rigged up with a very heavy rotating mass, to provide surge?
My HF chipper has a large, heavy steel disc. Very different feel when rope starting vs. most power tools.
When chipping 2" branches, that flywheel is what does it. If allowed to suck in the branch it does so too fast and slows to a stop after a number of turns.

I reread the paragraph about gas engines. Did not know that. This thread could be merged with my Sizing a whole house generator for a 3 Ton Air Conditioner

Most consumer-grade generators spin a 3600 RPM, and the rotor steel laminations with copper windings are quite heavy. Lots of inertia already.

Industrial-grade generators spin at 1800 RPM. I recall at Generac they prototyped a large 3600 RPM generator. Spun an amazingly long time after the engine was shutoff so was deemed a safety issue.

Would be interesting to have the AC thermostat start/stop the generator, and while running will charge the relatively smaller battery set for the inverter.