50/ 60 hertz

[VoltzElectrical]

pardon me if i should know this, but I don't, so hopefully someone can help.

Why does the frequency matter? What things are affected by the difference in frequency, and how?

Cheers

 

[Knobhead]

Have a look at Utility frequency - Wikipedia, the free encyclopedia it may answer your question.

 

[VoltzElectrical]

had a look. Brain hurting now. It's a complex subject but the article goes someway to answering my question. Problem is, it's not the sort of thing i have much everyday use for, much like a lot of the theory I crammed for my exams, so it's ebbing away. I try to keep it fresh my reading posts on the forums but still have to ask dumb questions to clarify things in my own feeble mind.

Thanks, and sorry

 

[Helm-Electric]

Well 50Hz (50 Cycles per second) is the frequency (how fast) the AC sign wave moves back and forth from source to load and back again. If it slows right down (too much load), this can put strain on the generators at base load power stations. As a result load shedding would have to occur to bring the frequency back up again. Just imagine a car driving up a hill.... eventually you need more power to maintain momentum.

 

[plugsandsparks]

Must admit have often wondered why 50 or 60 especially as its crap for lighting, having a quick look at the wiki did help with the compromise decisions made to make it 50 or 60 rather than 10 or 400.

 

[boberty]

One of the diffrences is that the bodys nervous system works at 50 hertz, so if you get a shock you cant let go as everything is working at the same rate. However our friends across the pond use 60 so this is'nt as big an issue as back here in Blighty.

 

[cymroaur]

Sort of related: that's why UK television is 25 frames per second, and the US run at 30 fps - half the mains frequency. Otherwise the cameras pick up the strobing of the lights.

 

[plugsandsparks]

One of the diffrences is that the bodys nervous system works at 50 hertz, so if you get a shock you cant let go as everything is working at the same rate. However our friends across the pond use 60 so this is'nt as big an issue as back here in Blighty.

Yep and half the voltage as well, bet they can still manage to kill themselves though

 

[ian.settle1]

Frequency can also have an effect on the speed of motors

 

[Knobhead]

Transformer iron losses, saturation level. Motor speed, iron losses, heat generation. Florescent lighting flicker, choke losses, choke let through current.

Need I go on. You will have to read up on your own.

 

[La Poste]

I didn't realise frequency dropped with increase in load until I read this thread.

 

[Helm-Electric]

I didn't realise frequency dropped with increase in load until I read this thread.

Without a doubt! Hence, if large amounts of load dropped off, the frequency would shoot back up again... If this happened too fast (rate of change of frequency), there would be the risk of generators tripping off at power stations, which in adverse circumstances, a chain reaction would cause huge black outs. This situation can be serious if a see-saw effect in frequency occurs. The New York black out which happened a few years back was due to this if I remember correctly.

Maybe as recently as two years ago, a power station in the south of England tripped off. This sudden loss of generation caused the frequency to dip for ms which resulted in Longannet in Scotland tripping a generator. This is the closest we came in a while to a UK wide black out. Thankfully Hydro stations were ramped up quick enough to get MWs back onto the transmission system.