harmonic distortion filter for generator

[The motor guy]

I was going to buy a Honda generator since it is very safe for electronic devices such as computers. My friend told me today that they make filters that filter out "dirty" electricity. What are these called? Most generators seem to say around 8 percent for harmonic distortion and I don't know if that's stable enough for computers and that sort of thing. Anyways, anyone know what these filters are called? I can't find any. I figured I would buy a cheaper generator if I can just plug in a filter to it.

 

[Rand]

line conditioner?

looks like anything the removes significant distortion is quite pricy

would be cheaper to buy an inverter generator and not need it.

 

[Ramblejam]

Originally Posted By: motor_oil_madman
Anyways, anyone know what these filters are called?


A filter isn't going to do anything for you in regards to producing power suitable for sensitive electronics -- you'd need something capable of outputting pure sine-wave AC. There are many inverters on the market (DC to AC) that do just that.

With that said, I'd rather have a 2000w invertor generator for emergencies. Around $500 on Amazon.

http://amzn.com/B004919NEK

 

[Donald]

A filter cannot fix a poor sine wave. It may help some with distortion on a good sine wave.

 

[spackard]

A double-conversion UPS.
They're expensive. Maybe twice the price of that 2kW Hyundai inverter generator Ramblejam linked to above. And, the Hyundai is doing internally about the same thing the double-conversion UPS does.

 

[rjundi]

My computer equipment has never been bothered by a Rigid generator that is non-invertor. However I use laptops with a AC charger and plugged into a $40 APC UPS.

 

[Quest]

those are typically referred to as "line filter" or "line conditioner".

double-conversion sine-wave inverter is the holy grail, but I see absolutely no need for it in terms of computer use, citing that any dirty AC line power gets converted into DC first before switching begins.. (SMPS), so harmonics in AC line has no impact to the SPMS secondary output.

My concerns with running computer PSU (SMPS) using gennie is surge or sag, for some wide-band (100VAC to 240VAC no manual-switching) PSU doesn't tolerate sagging very well, some do.

Q.

 

[Cujet]

Don't purchase a crummy quality generator. You don't need to go with a "Honda" brand genset to get quality power. Take a look at Northstar brand, by northern tools.

It's not likely your computer will care about slight sine wave distortion. They are switching power supplies and will work off of nearly any type of power.

But, microwaves, motors and other devices (such as UPS's) won't like poor quality power. Some UPS's will refuse to function at all. With that in mind, spend a few extra dollars and get a genset with known quality power.

A really good choice in 13HP portable generators: http://www.northerntool.com/shop/tools/product_200467366_200467366

A nice smaller unit: http://www.northerntool.com/shop/tools/product_200467313_200467313

 

[Cujet]

There is more to a quality generator than just a good sine wave. The engine quality is important, as is the governor control over the engine (and the resultant frequency of the genset under load/no load conditions)

Many of the cheapest gensets have plastic end bells and the bearings/slip ring holders get hot, melt the plastic, and fail at the worst possible time.

Also, it's common to have crummy wiring in Chinese gensets. No need to deal with this during an emergency. Spend a few extra dollars, get a quality unit that needs nothing else to work properly and store it inside, without any fuel in the tank or carb. It will last a lifetime!

 

[The motor guy]

I was wondering about the northstar generators. They have like 6 percent harmonic distortion and the Honda I was looking at was like 2%. I was looking at the Honda eg6500cl.

http://www.electricgeneratordepot.com/ho...one-piece-frame

 

[The motor guy]

what do you guys think is better? The northstar 8000 watt or the Honda 6500? btw the northstar is actually only 6600 running watts.

 

[Cujet]

I'd go on HP, Or, engine displacement, not the watt ratings..

Generator head efficiency is unlikely to be much different. And quality gen heads are likely to produce very similar sine waves. I have to wonder where the 2% sine wave distortion spec comes from. That's very unlikely in a single cylinder powered, non inverter genset. The power pulses will "speed up/slow down" the rotor more than that under heavy loads.

9HP, 270cc's makes about 4000-4500W maximum.
11HP, 330cc's makes about 5000-5500W maximum.
13HP, 390cc's makes about 6500W and so on.

To elaborate a bit, 746 watts = 1HP. When gen head efficiency is NOT taken into account, 10HP can produce exactly 7460 watts. BUT, these small generators are about 75-80% efficient at full load, or just under 6000W under IDEAL conditions, standard temperature and pressure conditions, high quality gasoline and so on. It's no wonder that a 10HP generator gets a maximum rating of 5500W.

 

[Cujet]

Originally Posted By: motor_oil_madman
what do you guys think is better? The northstar 8000 watt or the Honda 6500? btw the northstar is actually only 6600 running watts.


Either one will be just fine. I'd guess the Honda is likely to charge a bit more for the quality you get. And, again, either one will make EXACTLY the same "real world" power. Same engine!

 

[Quest]

Any gennies will do fine so long as the waveform is capable of starting my AC motors (fridges, etc.) and not too-distorted enough to make them hum.

any other electrical devices including SMPS power supplies don't care about harmonic distortion (it won't affect the quality on the secondary/output side regardless of what you feed in, period).

Q.