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New Here , Do I belong Question

New Here , Do I belong Question

New Here , Do I belong Question

(OP)
Im a Machinist by trade not an Engineer, can I ask about small standby generators here, or should I go elsewhere?
Or can someone recommend a good Forum for queries. I have joined and asked at another Forum, with no or little response.
Thanks and if Im in the wrong place sorry and I will ask to be removed.

RE: New Here , Do I belong Question

I think that you fit in here very well.

Go on and ask your question. There's one guy here (Waross) that knows everything worth knowing about gensets.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: New Here , Do I belong Question

(OP)
Thanks, I have a EM6500SXC Honda Gen. Canadian Model.

Bought it for cheap, been sitting a long time and very dusty. So I proceeded to take it completely apart and clean up and see what kind of shape its in.
Its putting out 113 - 115 V , is it not supposed to be 120?- Yes under load. Its seems to be putting out 220 on the 220 outlet.

How hot should the Gen. be after running under moderate load for half an hour,I can lay my hand on it buts its quite warm?

Is there any way of adjusting the voltage on said Gen.?

Is it ok to let the Gen. run for a while without any load at all ?

I can't seem to find a Shop Manual for it, anyone know where I can find one? There is one on the big auction site but the Model is different.
Thanks , any info would be appreciated.

RE: New Here , Do I belong Question

115/220 isn't bad, but could be higher. Check the frequency of the generator output, if you have a meter that does this.
I expect this unit will have a v/hz type voltage regulator, meaning voltage will change with frequency. It should run about 61-62 hz no load. Engine speed is directly proportional to frequency. There should be an adjustment on the carburetor for engine speed.

Perfectly normal for gen end to get warm with load. Remember that current flow creates heat. Wont hurt it running with no load.

As for a manual, if you cant find one online I would try the honda dealer.

RE: New Here , Do I belong Question

This was on Honda's site, http://cdn.powerequipment.honda.com/pe/pdf/manuals...

Here is a link to a site with manuals available in four serial number ranges,
http://powerequipment.honda.com/generators/models/...

Most of these units used Honda's "intelligent AVR" and I don't think they had any adjustable voltage trim. A company I used to work for had several and their voltage output ranged from 109 to 122 VAC. This size unit should have a voltage selector switch, either 120 only or 120/240. as I remember in the dual voltage position the 120 output seemed to always be slightly lower. Never sure why but since they did the job we didn't pursue trying to "fix" it.

They seem to tolerate low loads well for long periods of time, at least in my experience.

The service manuals always seemed to be hard to get, again in my experience and in my area, maybe someone else has a different experience. Honda is about the only source unless you happen to find one on ebay.

If you can still put your and on it it's likely running pretty cool. The only time I every ran into a heating problem with them was a unit used on a job that sucked a bunch of leaves into the fan shroud. If its been sitting for some time night not be a bad idea to give it a good cleaning, other than that they always seemed to be a good product, I have a couple of smaller ones of my own based on that experience.

Hope that helps, Mike L.

RE: New Here , Do I belong Question

(OP)
Been to the Honda Dealer, no luck ,its 14 years old and no longer "Supported"
If I were to get a Meter with frequency capabilities, where is it checked?

RE: New Here , Do I belong Question

(OP)
One more thing, It does not have a 120-220 selector switch it can run both simultaneously.

RE: New Here , Do I belong Question

Voltage; First check the speed. A typical speed for a 60 Hz generator at no load is 3708 RPM. Speed drop should be proportional to the load being 3600 RPM at either 5500 Watts or 6500 Watts, depending on the whim of the designer. The speed often affects voltage.
Apart from that, 113 to 115 Volts is acceptable. Few people realize how much the nominal 120 Volts from the utility varies during the day.
Heating: Warm is OK. At full load it will be painful to hold your hand on the generator for any amount of time.
Be guided by catserveng's advice.
A good cleaning is a great idea!

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: New Here , Do I belong Question

(OP)
If you read my second post , the whole point of taking it apart was for cleaning.
Thanks

RE: New Here , Do I belong Question

Frequency is checked at the output receptacles, same as voltage. As others have said, 113V is sufficient so not worth buying an expensive meter.

RE: New Here , Do I belong Question

If you can find an old electric clock with a motor drive, you may be able to use it to check the frequency. Most of the old motor drive clocks used a synchronous motor that locked on to the frequency. Plug it in and let it run for a minute, timed by a reliable wristwatch or stop watch.
If, after one minute timed the clock reads less than one minute, the generator is running slow.
If, after one minute timed the clock reads more than one minute, the generator is running fast.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: New Here , Do I belong Question

You have both 120 volt and 220 volt outputs, may I assume you are a US generator owner? Should be 60 Hz output.

In the US, we are required to have a different type of plug (socket) for 220 volt compared to 120 volt sockets, and each 120 volt socket will have different matching sockets (holes) for each different current that can safely be transmitted. 115 volt is probably "adequate" for most emergency and consumer applications, but listen carefully to what the other writers are saying.

Post a photo of your output plugs. Almost all auto part and hardware stores have multimeters available that can be used to measure both AC and DC voltages, some have current (ammeter) displays and plugs as well.

If you are uncomfortable with generators - and by cleaning the thing I don't get that impression - take it to a nearby electric maintenance company/ commercial contractor (for example, Wade Electric in Kennesaw/Marietta GA) and they can measure output for a nominal fee.

RE: New Here , Do I belong Question

(OP)
I like the clock idea, and yes I'm pretty comfortable working on most things except electrical I'm lost.
Its a Canadian Gen. it has both 110 and 220 plugs that can be used simultaneously. I have 2 meters, analog and digital but neither read Hz.
As I said Im getting 115 and 220 on my meter, just curious about the 110 side and from what most have said don't worry about it.
I had it right down to bits to clean it and its pretty simple to do, but trouble shooting electrical has always been a crapshoot.

RE: New Here , Do I belong Question

(OP)
So I borrowed a meter, got 52 Hz at about 3500 rpm, max rpm is rated at 3825. Should it running faster than 3500?
I think I might have to bring it in for a tune up.

RE: New Here , Do I belong Question

It should be 3600 RPM at full load (61.8 hz). Try 3708 RPM at no load. Your clock should register one minute in 58.25 seconds. That assumes a 3% droop governor. 3% droop is by far the most common setting on gen-set governors. The voltage will probably come up when you get the frequency up to 60 Hz.
Under Frequency Roll Off is a common feature on Automatic Voltage Regulators. This feature cuts in at about 57 Hz (47 Hz on a 50 Hz generator). Below 57 Hz the UFRO feature of the AVR drops the voltage in proportion to the frequency drop.
Honda may not and probably doesn't follow industry standards as far as governor and AVR settings, but regardless, low frequency is often accompanied by low voltage.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: New Here , Do I belong Question

Um.. a little deconfusion here:

Quote (waross)

It should be 3600 RPM at full load (61.8 hz)
Should be 60.0Hz

The unloaded 3708 RPM should be 61.8 hz.

Keith Cress
kcress - http://www.flaminsystems.com

RE: New Here , Do I belong Question

(OP)
So at 3708 rpm its putting out 60Hz.
If I plug in a light bulb it wont be putting out 60Hz. Is this correct and will it not harm things . Or should it run at max rpm whenever something is plugged in?

RE: New Here , Do I belong Question

(OP)
I tried running my Tablesaw of it , 220single phase 3 hp 14.4 amp would not start it, it would turn the blade but no go. Should a 6500 gen be able to start that kind of a load.

RE: New Here , Do I belong Question

Quote:

So at 3708 rpm its putting out 60Hz.

Wrong!

3600rpm:60.0Hz
3708rpm:61.8Hz


What EXACTLY happened when you applied power to your tablesaw?

Keith Cress
kcress - http://www.flaminsystems.com

RE: New Here , Do I belong Question

(OP)
Ok got Hz set at 3700 rpm, but still won't start my saw?
It will spin the blade -starter switch makes some clicking noise but won't contact or start the motor. I don't want to fry something so I just hold it for a few seconds and have not tried since.

RE: New Here , Do I belong Question

(OP)
Electric Motor Wattage Usage
Electric motors present a special problem. They require up to three times their rated wattage to start.
Example: an electric motor name plate states 5 amps at 120 volts, 5 amps x 120 volts = 600 watts.
Multiply this by 3. This will show the starting watts needed. 600 watts x 3 = 1800 watts to start.
Some motor name plates will show starting watts higher in some case 9 times higher, check the name plate.
******** ******** Approximate Starting Watts *
Motor
HP
Rating Approximate
Running
Watts Universal
Motors
(small appliances) Repulsion
Induction
Motors Capacitor
Motors Split
Phase
Motor
1/8 275 400 600 850 1200
1/4 400 500 850 1050 1700
1/3 450 600 975 1350 1950
1/2 600 750 1300 1800 2600
3/4 850 1000 1900 2600 x
1 1000 1250 2300 3000 x
1-1/2 1600 1750 3200 4200 x
2 2000 2350 3900 5100 x
3 3000 x 5200 6800 x
* - Always use starting watts, not running watts, when figuring correct electrical load

I see now why, my saw won't start, some charts say up to 9 times the running load to actually start.

RE: New Here , Do I belong Question

Some generators will lug the prime mover down under heavy motor starting loads and drop the voltage and frequency. In an imitation of a VFD they will then regain speed as they bring the motor up to speed. It has to do with the Volts/Hertz ratio and reduced voltage AND frequency.
Most small generators will not. More likely the heavy starting current will cause voltage collapse.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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