50Hz or 60Hz... what's the deal?

[Looking]

I searched the threads here, but I still can't find the answer. I am not an electrical genius, so I am wondering what is the difference between a 50 or 60 Hz generator (other than the 10 Hz, or the fact that Europe is on 50 Hz)

Thanks.

[bossk]

This may shed a little light on your question!

Utility frequency - Wikipedia, the free encyclopedia

[newpbs]

I'll share what I know and ask more questions so that others that Know more than myself can answer.

In the U.S. we have 60 Hz which means that the alternating current reverses 60 times every second. This frequency is very constant and some equipment relies heavily on this constant frequency. Other places, Europe and I believe Canada, has the current reverse at 50 times each second. Some things will operate fine on either current. If the equipment is designed to run on 50 or 60 Hz there is no problem.

Here is the question that I have for you. What specific concerns do you have? Is there something that you are concerned about operating either here or elsewhere?

I'm sure there are folks here with more information on the subject. If you can provide more information, you will get a better result.

Good luck, Paul

[bossk]

I'm pretty sure we're 60hz up here in the North

[brak]

considering that real frequency varies quite a bit (it is not unusual to have variation of 10-15% even in US) i think the number is more of a guideline.

[sailboy21]

Originally Posted by brak

considering that real frequency varies quite a bit (it is not unusual to have variation of 10-15% even in US) i think the number is more of a guideline.

No.. actually it is pretty much 60.. all the time. Not really relevant to the discussion but some clocks are even timed solely by line frequency. It really is that stable.
Frequency isn't important to most AC devices you might find on a boat. Voltage is, however, and if you go somewhere that has 50 Hz use that as a clue to get the appropriate transformers to step down the voltage.

[SEMIJim]

Originally Posted by sailboy21

No.. actually it is pretty much 60.. all the time. Not really relevant to the discussion but some clocks are even timed solely by line frequency. It really is that stable.

Correct. Here's the last five days of data from my UPS at home, for example:

freq: hi: 60.2 @ 22:04:36, low: 60.0 @ 00:00:03, avg: 60.0 (+/- 0.0)
freq: hi: 60.2 @ 01:34:35, low: 60.0 @ 00:04:35, avg: 60.0 (+/- 0.0)
freq: hi: 60.0 @ 00:07:49, low: 60.0 @ 00:07:49, avg: 60.0 (+/- 0.0)
freq: hi: 60.2 @ 23:09:10, low: 60.0 @ 00:08:47, avg: 60.0 (+/- 0.0)
freq: hi: 60.2 @ 01:29:12, low: 60.0 @ 00:09:10, avg: 60.0 (+/- 0.0)

Those highs of 60.2Hz might've been just one sample out of the entire 24-hour period, and it's still only a 0.3% change.

Originally Posted by sailboy21

Frequency isn't important to most AC devices you might find on a boat.

Well... That's not necessarily true. All kinds of things, such as motors (as in compressors) to anything with a transformer might "care." Your smart charger might care.

newpbs, I'm fairly confident Canada is on 60Hz. Don't know about Mexico. Much of Europe is on 50Hz (and 220V).

To the OP: If you're a N. American on a N. American boat: You want a 60Hz generator. However, unlike the power utilities, I can guarantee you 60Hz is only the "wishful thinking" rating. In reality its output frequency will wander all over creation.

Here's some frequency data from when we've been running on generator, during Yet Another DTE Failure:

freq: hi: 60.0 @ 12:05:38, low: 53.8 @ 06:25:38, avg: 58.2 (+/- 1.4)
freq: hi: 60.2 @ 21:06:17, low: 52.8 @ 08:46:17, avg: 59.5 (+/- 1.1)
freq: hi: 60.0 @ 00:09:30, low: 55.5 @ 18:09:33, avg: 59.1 (+/- 1.1)

Those are some pretty serious excursions. The various AC-powered clocks in the house are utterly worthless when this happens.

Jim

[sailboy21]

Originally Posted by SEMIJim

Well... That's not necessarily true. All kinds of things, such as motors (as in compressors) to anything with a transformer might "care." Your smart charger might care.

Yeah.. I was probably a little off on that statement. I like how Wikipedia puts it:

"Unless specified by the manufacturer to operate on both 50 and 60 Hz, appliances may not operate efficiently or even safely if used on anything other than the intended frequency."

That said, any charger I have looked at recently has the 50/60Hz rating. If it claims to be "smart" and "marine" it had better work if I sail across the sea! Also common laptop and desktop computers can run on either. The label plate should say what power the device can run from i.e. 120/240 VAC 50/60Hz. You can change voltage but you can't change frequency so make sure what ever you plug in isn't going to blow up! If you have ever been in an environment where the line frequency drops (like an older heavily loaded genset on a ship) you would be familiar with the moan of induction motors running slower, lights flickering at a different rate, and the EO spewing cuss words... Never mind, pesky flashbacks

[Sapperwhite]

Bossks wikipedia link is a good one, take a look at the map at the link and you'll get an idea of when different freq systems are used. Basically, if you live in north america, and everything (electric powered) you own and buy is for north american markets, then get a 60Hz gen set.

You won't see a variation of 10% in frequency in a modern system. Frequency is strictly controlled, and frequency relay schemes will function to control frequency way before the sytem gets close to a 6Hz varition.
In the east, we control time error (frequency variation) at 2 seconds. That means we correct system frequency when it drops from 60.00Hz to 59.98 (or from 60.02 in high frequency conditions).

Under frequency relays are set differently, but generally around 59.3, 58.5, and 57.9Hz for three levels of load shedding. Those values aren't golden, just guidlines. Some areas have five levels of under freq relays, and some areas have them set at different levels. These relays will essentially blackout designated amounts of load to regain system frequency to prevent cascading whole system loss (whole system blackout). Generation trips at 57.5Hz (also not golden. Different units are set differently, but in that proximity.)

Its a long boring story, but i can direct anyone interested to a ton of information that is publicly available if you are really interested in generation and transmission systems, relays, controls, regulations, economics, markets, blah blah blah

[Sapperwhite]

Originally Posted by SEMIJim

To the OP: If you're a N. American on a N. American boat: You want a 60Hz generator. However, unlike the power utilities, I can guarantee you 60Hz is only the "wishful thinking" rating. In reality its output frequency will wander all over creation.

Here's some frequency data from when we've been running on generator, during Yet Another DTE Failure:

freq: hi: 60.0 @ 12:05:38, low: 53.8 @ 06:25:38, avg: 58.2 (+/- 1.4)
freq: hi: 60.2 @ 21:06:17, low: 52.8 @ 08:46:17, avg: 59.5 (+/- 1.1)
freq: hi: 60.0 @ 00:09:30, low: 55.5 @ 18:09:33, avg: 59.1 (+/- 1.1)

Those are some pretty serious excursions. The various AC-powered clocks in the house are utterly worthless when this happens.

Jim

Yes, a single generator doesn't have the system stability or control schemes that an entire transmission RTO has. All my prev post was in regards to transmission and distribution systems, not a single generator.

You probably will see a big frequency drop on your single gen when big load like an AC unit or refrigerator comes on.