Question,,,, are you sure it is 100 cycle ?? I thought it was 100 to 105 volts, 50 hz. If it is 50 hz then yes, universal (50/60 hz) tools would work. But only tools listed as 50/60 hz, or just 50 hz.

But then that's based on my dim memory..

 

Sandy,

I looked again to make sure I wasn't reading that wrong. It states 115 volts 9 amperes AC 100 HZ Receptacle. Here is a link to the manual, it is on page 13. Maybe I am looking at this all wrong. I have never heard of any devices in the US using 100 hertz. Any help would be appreciated. Could this possible be a DC outlet? It seems like I read in another manual about a dc receptacle on a welder generator.

http://www.millerwelds.com/om/o411n_mil.pdf

Thanks,

Jason

 

Well you got me Jason. It flat says AC in the book. Well have to wait and see what others come up with.

Sorry guy.

 

It sounds like they stuck a 4 pole generator on a gas engine for a higher cycle rate. The higher the cycle rate is better for the rectifier and yields better DC.

You need to test that plug with a meter that will show frequency. I suspect that on the power setting the voltage will be 1/2 of the weld setting and frequency will be 50hz. If this is the case DO NOT USE IT! Just put some tape over it so no one plugs in since it WILL damage most items plugged into it. The exception would be lights (incandescent) they will work regardless of frequency.

Ok, the problem is 120v is not 120v....
Confused yet? In a AC system the voltage is NOT constant but rather continuously changes from -170v ~ 0v ~170v RMS value is 120Vrms or 120 volts
By increasing you cycle rate you will change the RMS value and most likely will introduces more heat into your equipment.

Note:
Not all meters can show RMS values They are more $$

 

Look at the schematic on page 31 of the pdf manual. Notice that, the "115v ac rc1" 100hz outlet is supplied by an auxiliary winding in the welder exciter? A separate source from the "power wdg" circuit, which supplies the other ac outlets.

Since "power wdg" is out of circuit during welding mode operation. I would say the 100hz was a
compromise, -of the exciter's electrical characteristics- to be able to supply some 115v current while in welding mode. This power was probably intended for non frequency sensitive loads such as lights.

 

I would say the 100hz was a compromise, -of the exciter's electrical characteristics- to be able to supply some 115v current while in welding mode. This power was probably intended for non frequency sensitive loads such as lights.

Usable byproduct of the welder? Sounds right. An incandescent bulb wouldn't care. The voltage might be a little lower, so the light might be more yellow than we are used to. 9 amps would run a lot of lights. Bad thing is that I had the bobcat 225 with a similar "one odd" receptacle on it and can't remember what it was. Never used it is all I can recall.

Embarrassing.

 

Jason, Miller is warning not to use equipment that MUST have 50/60 Hz power. This would include items using INDUCTIVE motors like typical fans, pumps, BENCH grinders and the like.

Your average motor driven hand tool like drills, angle grinders, and sanders use UNIVERSAL motors that are not at all frequency dependent. These will work fine on 100 Hz power. You can recognize almost all tools that use universal motors by the presence of brush holders on the sides of the motor or, if you can look inside the body of the tool, the presence of a commutator. In some cases the brush holders of universal motors are not visible from outside of the tool. However, this is so rare as to be of no practical concern.

Universal motors are used in hand tools because they offer a very high power-to-weight ratio and they have greatly increased torque as they are lugged down under load. They are called "universal" because the basic brush-type motor WITH WOUND STATOR (i.e., NOT a permanent magnet for the field excitation) can operate equally well on AC power of any (practical) frequency or on DC power. This is because the field and rotor magnetic polarities BOTH change in synchronism with the AC power polarity each half cycle, maintaining the torque in the same direction, independent of applied power polarity. So the motor continues to run fine.

In a PERMANENT MAGNET, brush-type motor the rotor polarity changes each half cycle of the applied AC power but the permanent magnet field never changes polarity. So on AC power, a permanent magnet, brush-type motor would just sit and chatter without developing any net torque (until it burned out). Not to worry, though, because you will never run into a PM motor on a tool with an AC power cord unless there is a built-in rectifier or other electronics to convert the power applied to the motor to DC.

"Cordless" tools do usually use PM motors because the power from the batteries is DC and because PM motors are cheaper to build than universal motors because they don't have the labor to wind a field. One caution would be about operating cordless tool chargers on your 100 Hz source because they generally employ transformers to step the voltage down and isolate the tool from the line. In almost all cases these will work fine on 100 Hz power. But just to be safe, monitor charger temperature or ask the manufacturer.

Me! states, "By increasing you cycle rate you will change the RMS value and most likely will introduces more heat into your equipment." This is not true. Rms value is independent of frequency, but is strongly dependent upon waveform. Thus, a +/- 170 volt peak (340 volts peak-to-peak) pure sinusoid is 120 volts AC RMS completely independent of frequency.

Go ahead and use your auxiliary power receptacle with confidence for common, hand-held power tools WITH BRUSHES.

awright

 

Jason, Miller is warning not to use equipment that MUST have 50/60 Hz power. This would include items using INDUCTIVE motors like typical fans, pumps, BENCH grinders and the like...

Your average motor driven hand tool like drills, angle grinders, and sanders use UNIVERSAL motors that are not at all frequency dependent. These will work fine on 100 Hz power...

Go ahead and use your auxiliary power receptacle with confidence for common, hand-held power tools WITH BRUSHES.

awright

I wonder really what the manufacturer was thinking about when they added this feature.

For sure, an induction motor designed for 60hz could run at about 70% overspeed.

I don't know about the hz sensitivity of some of the 'fisticated advances in motor start and speed control. Maybe awright or me could bring me up to speed!

Test carefully. I instantly smoked a little pencil grinder when I plugged it into the 115dc outlet of an sa200.

 

What the manufacturer was thinking? Trying to give operator some power while he was welding. In most cases, works flawlessly. Miller was using an air cooled engine with cast iron rods to power a welder. To get 60 hz, you must run 1800 or 3600 in the real world. While 1800 worked great for power, noise, economy, etc., the power output of the engine was limited and that is why you saw 5000 watts maximum. To deliver more power from the engine, manufacturers revved up to 3000 rpm - fine for welding. If they tried to go on up to 3600 with the early CCK Onan cast iron rod engines (allowing power at 60 hz ) one of the rods would quickly come through the side of the block. So, at that time, machines ran 1800 for power and 3000 for weld. Worked great until Lincoln introduced 7000 watts in about 1978 by running at 3600 rpm for any job, power or weld, and the race was on. Miller's Legend still runs the 1800/3000 rate. The early 16 hp Blue Star Welders did the same in 1977 and later added the 100 hz receptacle for power while welding. Still one of the most amazing success stories in our industry. Here was a 500 lb welder that sold for 1000 that would do what a 1200 lb Lincoln would do, but give you ac power for variable speed tools and do it at idle speed to boot!
No, that power while welding is a good thing. Just as ac power at 1800 - idle - is a good thing. On the other hand, with the modern engines running aluminum lightweight rods giving 5000 to 6000 hours, what difference does it really make from a practical standpoint? What with a realistic 10000 watts available allowing you to plasma cut 7/8" in the field or run your house in an emergency. These new machines are truly wonderful in their capabilities are they not? weldersales

 

Go ahead and use your auxiliary power receptacle with confidence for common, hand-held power tools WITH BRUSHES.

This was already mentioned but I'll ask it just to be sure; what will the RPM be on these hand held tools?

If I have an angle grinder that was built to run at 11,000 to 13,000 rpm and have a wheel on it spec'd for 14,000 rpm---will it be okay?

 

What the manufacturer was thinking? Trying to give operator some power while he was welding... weldersales

Thanks for that insightful explanation, weldersales.

By the way I certainly didn't intend "what where they thinking" to be derogatory, whatsoever.
I figured that there was some logic to the compromise.

 

I have never heard of any devices in the US using 100 hertz.

Military generators produce 400 cycle power. At least they did decades ago when I was in the Navy working on aircraft. Rationale was so civilians wouldn't steal 'em and use 'em. Sorry for the thread hijack.

 

400 Hz equipment such as for aircraft and sonar and other stuff is very power sensitive. 400 Hz provides a much cleaner power than 60 Hz.

 

69 chevy said, "Military generators produce 400 cycle power. At least they did decades ago when I was in the Navy working on aircraft. Rationale was so civilians wouldn't steal 'em and use 'em."

Actually, 69 chevy, 400Hz power for aircraft originated because alternators, inverters, motors and transformers operating on 400 Hz power are inherently much smaller and lighter than the same function operating on 60 Hz power. Much less steel and copper required for the function, thus lots of weight saved with 400 Hz power and more payload can be carried. It's certainly true that 400 Hz aircraft equipment can't be used by "civilians" for home applications, but that was not at all the rationale for adopting 400 Hz for aircraft applications back in the early days of aviation.

rat4spd, you can get much more power out of small, light equipment built for 400 Hz than you can out of equipment built for 60 Hz, but 400 Hz power is inherently no "cleaner" than 60 Hz (or any other frequency) power and you still need the same voltage and current for a given function at either frequency - you just don't need as much iron and copper.

Sandy, your universal motor powered tools will operate at the same speed on 100 Hz or on 60 Hz because the speed of universal motors is NOT related to the power frequency. This is NOT the case with your ordinary induction motor used on most (but not all, these days) bench or floor-mounted power tools. Induction motors operate on totally different principles than universal motors. Induction motors are fundamentally rotary transformers in which the speed of the rotor is (almost) locked to the speed of "rotation" of the magnetic field created by the AC current passing through the stator windings.

The speed of rotation of the MAGNETIC FIELD of an induction motor is exactly related to the power frequency and the number of poles in the stator - 3600 RPM for a two-pole stator, 1800 RPM for a 4-pole stator, 1200 RPM for a 6-pole stator, and so on.

"Synchronous" motors (which you will rarely find on shop equipment) ARE exactly locked in to the speed of the rotating magnetic field. That's why they are used in clocks and timers and other equipment that requires exact speed. They do not rely on transformer action to excite a magnetic field in the rotor. Rather, they either have slip rings and windings on the rotor or the rotor has "salient poles" (poles that stick out) or magnetic characteristics that hold the magnetization of the rotor in a fixed position on the rotor. The fixed position of the magnetization of the rotor of a synchronous motor is what lockss the rotor to the exact rotating speed of the magnetic field of the stator.

Ordinary induction motors are NEVER locked at the exact speed of rotation of the magnetic field because they REQUIRE "slip," that is, the difference between synchronous speed and actual speed, to develop torque. The transformer action that induces circulating currents in the aluminum bars of the rotor, thus producing the magnetic field of the rotor, actually operates at the slip frequency, not the power frequency. Thus, no slip, no torque. An induction motor running at synchronous speed has zero torque. In fact, an induction motor driven at above synchronous speed develops negative torque - that is, requires application of torque to the rotor from an external source - and acts as a generator, driving electrical power back into the power grid. This is exactly what wind turbines do.

Sorry to have gotten carried away. Be careful about getting me started. (The capitalization is not yelling at you, it is to focus attention on specific words. I haven't yet learned how to italicize text in these posts.)

awright

 

Hey Guys,

Thanks for all the replies. I have a small amount of electrical knowlegde, but obviously not much when it comes to these issues. I appreciate the knowlege shared in the posts. I now feel comfortable using my grinder without burning it up.

Question for Weldersales: I noticed in the earlier version (earlier than mine) of the AEAD that the outlet was DC 60 hertz. Was there a device being used in the 1970's that needed 60 hertz DC for welding? Just wandering. The more I learn, the better.

Thanks again,

Jason

 

On subs, the weight savings is an ancillary benefit.

 

... Question for Weldersales: I noticed in the earlier version (earlier than mine) of the AEAD that the outlet was DC 60 hertz...

Jason

Weldersales, may I ?

Hertz is cycles per second of Alternating Current. Direct Current does not cycle thus is not measured in hertz.

The statement DC 60 hertz would have been an error.

 

West Baden Iron, now that you bring it up, seems that in the early welding days, 60's, the AEAD had a dc shunt wound generator on the same shaft as the rotating field for welding. Had a commutator as Lincoln did and generated dc only which was fed through a rheostat to the revolving field to control welding output. They brought that dc out for auxiliary power while welding. These machines had a hinged side to give access to large knife switch that changed from weld to power. This was before we had inexpensive power diodes and used the large selenium rectifiers. We don't want to go back to those days!
Of course, Lincoln SA200's have always had only dc out for aux power. That's why you see those big black burn marks on the dc output on the front of half of the pipeliners out there - at some point someone plugged in an ac load, like a motor. The flash will definitly wake you up in the morning! weldersales

 

... had a dc shunt wound generator on the same shaft as the rotating field for welding. Had a commutator as Lincoln did and generated dc only... This was before we had inexpensive power diodes and used the large selenium rectifiers. We don't want to go back to those days!...

Or do we?
Those old purpose built, without compromise, dc generators are still the smoothest and most controllable welding power source. Would anybody disagree?

Well would ya? :laugh:

 

Tools that will generally run on any welder with a 120V output (DC, 50/60/100Hz): Handheld grinders, handheld drill motors, most variable speed motor tools (variable speed may not be available), toaster (non-computerized models only. Handy when work starts at 6), incandescent lights

Tools that will often work at other than 50/60Hz: SOME compact fluorescents (check with the manufacturer), most all continuously variable speed tools (with variable speed), SOME multispeed AC motors (check with the manufacturer first. Run only on the low speed in this case. Could be handy for a multispeed fan, for example. Try at your own risk)

DO NOT use fixed speed ac motors at 100Hz. The current draw will usually be lower than at 50/60HZ (but some motors will draw higher current) but the motor will try to run at a much higher than design speed, which can damage the motor itself, or what it is attached to. You don't want to find out what hapens when you overspeed a grinding wheel.

 

rat4sapd: True enough. But then, why do subs use 400 Hz ac power (assuming they do - I've never served on a sub)?

I would speculate that sub designers adopted the 400 Hz standard because there are many items of MIL-qualified 400 Hz equipment in the supply lines that are readily adapted to shipboard use. Since they have power systems that are completely independent from 60 Hz. shore power while at sea, it still makes sense to use well-proven 400 Hz equipment. 400 Hz power could easily be provided from ehgine-generator sets on shore for operating all systems while berthed.

And, even in a sub displacing many hundreds (thousands?) of tons, it wouldn't make any sense to adopt a power system that weighed 6 times more than a 400 Hz system to no technical advantage since they. also, have to balance weight against displacement and excess weight means less payload, even if it is a small percentage of total weight.

awright

 

awright, I agree. I would also think that smaller transformers, chokes, etc. could mean smaller equipment. That's probably a good thing on a sub.

 

Sorry about the error about the 60 hz dc. I read the manual wrong. It is somewhat hard to follow without printing and I thought that's what it was saying. I do realize hertz is inherently dealing with ac wave cycles, and not dc, but I thought maybe Miller had printed this in error. The earlier model seems about the same as mine except for the jack plugs, so I thought maybe they accidentally put dc instead ac for that receptacle.

Thanks for clearing up the confusion (mainly from me).

Jason