3 phase generator for single phase residential backup power

[@smithn.wesson495]

Very good video - You can explain this topic faster, easier and simpler to understand than some people who have Ph.D's in electrical engineering and are college professors. Well done!

[@victory5056]

Excellent video! I had always wondered where 208 came from. Great explanation with the oscilloscope.

[@johngnang6724]

This guy is way smart.I can watch his videos all day.

[@ChevyConQueso]

Great video. To the point, and verifies what I thought quickly. I've been looking at generators and am interested in some older diesel and .mil gensets, and figured it would be nice to be able to run 3 phase equipment that I don't own yet.

[@proles101]

Up to 10kva You can also use an appropriate sized 208/240 single phase transformer and connect 2 phases to the primary and you will get your 240 and keep the full rating of the generator. For above 10kva You can use an open delta transformer. when you do this you connect the primary as normal A B C , on the secondary use only A and C the outside phases on the primsry and secondary will draw the same amperage, but the B phase on the primary will draw the combined amperage of the outside phases.

[@power-max]

8:11 correction, you actually get 1.414 or sqrt(2) times more voltage than the 240V "RMS" rating we use to rate AC voltage. RMS means you take the AC waveform, you take the average over 1 cycle of the squared voltage wave. It's done this way because the peak voltage overestimates power delivery into a resistive load, and just taking the average would be zero because the 2 halfs cancel out! So for a more rigorous definition of RMS concept: Power dissipation in a resistive load is P = I*R = V^2/R = I^2*R. (R = V/I) (as voltage goes up, so does current. Doubling voltage quadruples power. P=I*V -> I=V/R -> P=V^2/R) To find the "equivalent DC power" voltage for a resistive load (heating elements and incandescent lamps mainly) it makes sense to work with V^2. Just take the average of (Vpeak*sin(2*pi*f*t))^2 over 0 rad to 2*pi rad using integration. Boom you got the idea of RMS! For sine waves it's 1.414

[@MrShawn305]

You're a boss. All of your videos are great, I love that you know what you're talking about and have good information.

[@andremendez456]

Do you have any information on Reconfiguring an MEP 805B generator set for single phase 120/240

[@GunneyRat]

thanks this is something I've been wondering about for quite some time

[@bbariceo]

Thank you. I've been looking online for backup generators and was wondering about 3 vs single phase power.

[@Magellan51]

Get an MEP 003A (MIL Standard) or an MEP 803A (TQG) which is a 10KW generator and set it to 120/240VAC by the S-8 Switch which is a series Delta configuration. You'll use L1, L3 and Neutral. 120VAC from L1-N and L3-N and 240VAC from L1-L3. This is the most ideal generator for a house and it will give you the same amount of amps of an 004A or 804A 15KW generator; 52 Amps per phase and won't unbalance the generator. The three phase, 15KW generator can only be configured to a Parallel Wye 120/208VAC or a Series Wye 240/416VAC and will unbalance the generator if you only use two of the three legs. This will eventually cause damage to the generator bearings and windings. You can also configure the 15KW in the same way as a 10KW (120/240VAC) by connecting the terminals the same way as the 10KW. You have to bypass the tap-change-board to do this configuration.

[@pashagilmore]

Great vid! I have a 10kw military genset…do I need to add an additional ground from the genny or will it be sufficiently grounded through the panel/house feed? Thanks!

[@SteichenFamily]

You mentioned that it's pretty easy to do a conversion to 120/240V as well. Do you have a video on that?

[@keithgray4901]

Good info. It would be cool if you did a video explaining what that selector knob on your genny that you showed at the last does. I have one on mine and not sure what it’s for. Thanks

[@scottlees5178]

The selector knob selects what the voltage and amp meter are reading

[@elliottdiedrich3068]

I did indeed find this video useful and thank you for making it.

[@cvpiDOTnet]

Thanks for this video, I have a M1031 that is my home backup power.

[@linctexpilot8337]

I Love your nice shop! I see you even have a Lister diesel in there!

[@MattVerley]

LincTexPilot Thanks! And yep; I used to have a 10HP lister clone that powered an 8kw generator head. I sold it a few years ago...I actually used it for a while as backup power for my house, but it sat in my shop for too long gathering dust.

[@carkrazd]

Thank you very much for your time in making these video's. I have watched many of them and always learn something. My Mep 005A is a bit over kill to run my house and shop even with a large amount of 3 Phase machine's. I also found a 3Phase panel to wire and run every thing. Thanks again for sharing you wealth of information.

[@bradphillips1407]

Am I understanding correctly that with this conversion, you can get almost the full rated output in single phase 120/240v? I know this an old video, but also is it possible to make this gen set work in two wire auto start? Maybe install a cascade controller? I’m looking at installing one for home back to work with my ATS

[@erlendse]

Nice explaining, quite visual. Even it doesn't actually apply to me, all appliances are 230V here and the power-grid is 3-phase. (in Norway)

[@howeird79]

I found a good deal on a 3 phase 120/240 generator. So if I’m understanding, I can pull down to single phase and be fine for everything? It’s a 21kw so I’d be running 14kw?

[@dennisd3401]

I would be interested in seeing how you hooked up the generator and through what switching ect. I as well purchased a used Kohler 20kw (inside sticker rates it at 25kw) that is on its own trailer. I would like to keep it on the trailer and have thought about a quick disconnect to the house/shop. Interested in your suggestions regarding a good way to make it happen. This generator has multiple ways to get various voltages based on which wires you join together baccording to the data plate. Thanks for your original video!

[@kellycarver2500]

Hi Matt, I'm a woman who has done many men's jobs, but for some reason I just CANNOT force my brain to deal with amps, volts, watts, etc..My brain just goes into auto SHUT DOWN. I love the idea of creating my own power, though, and I am trying to put together a system for my construction trailer, and a future off grid home. I do woodworking and other heavy stuff, too, so wouldn't be a bad idea to have three phase available..Please check this link and tell me if this wind turbine would work for a home and shop, Along with solar panels, a Missouri Wind and Solar 24 volt (which actually looks like two 12 volts together on the board) charge controller, with divert relay and LED meter, and a Schumacher 2000 watt converter. I will probably need the inverter (mislabeled a CONverter by Schumacher), lol, in the trailer/truck set up. along w solar panels, but this looked like such a good deal, that I just had to look into it..check it out..www.aliexpress.com/item/4000805448831.html?spm=a2g0o.productlist.0.0.1f675ad6OVtwcK&algo_pvid=c6049544-1c55-4f40-b857-355422f224fc&algo_expid=c6049544-1c55-4f40-b857-355422f224fc-48&btsid=0be3764315869061868712760eac88&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_ It's an 8000 watt three phase wind turbine..

[@haroldbottom3474]

Nice video..The smaller TQGs 5/10kW have a voltage reconnection switch inside the control panel.

[@kf5hcr176]

Outstanding, well done, Sir.

[@dlewis4647]

Wow, great content! Hoping you can point me in the right direction. I have a 1994 Generac 08976-1 1 and 3 phase diesel generator. It is missing a voltage regulator and the controls are really old and not working. Can you recommend a control and AVR to upgrade it? I assume its just wiring it up to the generator and engine?

[@snksshabin5809]

Great video! We have an older Tate 25kva genset. Hooked L1-L3 to the main breaker panel. 208v rock steady until I flip a breaker on. That leg goes to zero and the other leg shows 208. Any ideas?

[@isaaccoen-graham8867]

I picked up an old lister 8.5kva single phase gen the other day, the windings come out with what looks like 3 phase designations and are linked together some way to make it single phase. This is a plated single phase unit.

[@isaaccoen-graham8867]

From what i can make out there are 6 coils configured in two delta patterns

[@derprogenator2147]

Hi, I have a Diesel engine (60KW) that I can run for free on used plant oil, and a great big brushless 3 phase motor 7.5KW that I'd like to couple together to make a permanent generator for my house (which is wired for 3phase from the grid (220-240/phase, 50 Hz) here in Europe). An elec engineer once told me that if I do this I can easily pull the phases out of balance and move the 'zero' so that I might damage computer equipment (etc)on one of the phases, etc so it would be best to give up and buy a modern-ish generator with some kind of automatic/built-in balancing. Now, most generators will not be set up for biofuel whereas my diesel engine is. And, it's free. What do you reckon? Is there a reasonable way to balance the phases, or either build or buy some kind of add-on balancer to achieve my aim? Do modern generators (one suggestion was a tractor generator) really have balancing devices in them? Any help appreciated. And thanks for the videos you put up.

[@MattVerley]

It is rare to have balanced loads between phases on small generators; most generators are designed with specific per-phase current limits. As long as you don't exceed that limit, there should be no problem. Most generators have circuit breakers for each phase; as long as yours are sized properly, it should work fine.

[@mikesnyder3577]

Matt, I recently bought a 3 phase 125 kva lima generator that has the 4 cylinder detroit diesel. My voltage regulator board is fried and I'm not seeing any replacements online. Do you have any suggestions? Thanks Mike

[@Magellan51]

The new military Advanced Medium Mobile Power System (AMMPS) (If you can get them) MEP 1040 10KW generator is far superior to the old Mil Standard or TQG's. Digital controls and more reliable.

[@tjgeniale8672]

Hello. Any chance you can tell me how to wire a cummins generator single phase 240v ac for a back up generator there is a 4 lead connection that i can wire but i’m missing a wire. There is a 12 lead double delta i have all the wires for but I don’t understand how to wire it. Please help. Thanks

[@j.r.pierce7019]

You explain it to a level that even a caveman would understand. Thanks very educational

[@andyhofer6484]

How many kw do you end up with after converting to 1 phase for that gen? I am looking at A MEP 1050

[@sostahoe]

Any feedback on how I can utilize a CS8269 breakout box and still have 208 3 phase available for some old school machine tools ? I have a Dayton 4W118 genset that can be set for 240 or 208. Would I have to totally reconfigure the spider box ? is there a way to switch on they fly for each use ora way that would allow multiple plugs to be available ? Looks like it's one or the other, but not both. Is this a genset issue or a wiring issue ? I am just getting up too speed on the 3 phase / 2 phase. My question would be what is the benefit of running my machine tools on 208 3 phase rather than reconfiguring for running on 240. is there a efficiency issue or a power issue for the electric motors ? I will be getting my motor plate info later and see what they say.

[@cliedocladidahopper3094]

I wonder if an overrunning clutch till the backup generator comes on would be cool if till the power goes out would the machine start up or be disabled, many good overrunning clutches out on the market

[@richardmorse6984]

One issue will be the generator load imbalance, it is only using 2 phases, so the rotor will heat up, it would be better to split the DB board load 50%:50% on the heavy used of the 2 utility phases and hence then use all 3 phases, the generator will still have an imbalance but it will be less severe, you need a 4-pole transfer switch and you need to separate one of the utility phases in the consumer DB into 2 electrically isolated DB's fed from the same phase when on utility power

[@rogermccoin7122]

Hey there well done on your video I am taking a MEP005 that has been converted and going back the other way to 440 Three phase for a water ski cable drive system If i just work backwards will i end up ok Obviously i will need to make another bus bar anything else i should be aware of

[@chanceheimann919]

If you have a mil gen 3 phase your going to run single 120 and 208 but not going to run any 3 phase what do you do with the other hot leg?

[@Yohantube99]

Hello Matt, I currently have an MEP-804A, the generator is blown. I wonder if it is possible to rewind the generator to produce single phase power only. I am interested in using it as a backup generator for my house, but I would like to be able to use the full capacity of the generator without damaging it. I would love to talk to you more about it.

[@jimfejes6709]

can this procedure be followed for a MEP 816 B MILT GENERATOR?

[@amrmagdy926]

Thank you so much for your videos, please help how can I have the generator provide a 220 or near it current on a single leg so i can hook my house to it which is 2 lines 1 neutral and 1 positive, thanks !!

[@jasonmare33]

can you answer a qustion for me ? I have a three phase 125 amp auto transfer switch 277/480 .Will it work on a single phase 200 amp service panel ? thanks

[@magicfarmplantation1433]

I have a question for you sir. I have a 3 phases 220 v generator, that I bought in USA but I take it in Africa were power is single phase 220 v. Now I want to know how should I use that generatorto power my appliances 220 single phases. Thanks

[@popapoco]

Great great video man thanks I have a 208 3 phase generator and was totally stumped lol you saved me lol thanks

[@electromechanicalstuff2602]

I just bought an mep -002a 1981 930 hrs. Looks to be in good shape. Order the fram oil filter an am upgrading to spin on fuel filters. My question is do u ever prime the oil system before first start since who knows when the last time it was started. I have always done this to my hod rods after sitting the winter to prevent bearing damage I can't see this being any different. I will attempt to get as much oil in the oil canister as I can without making too much mess but I was thinking maybe prime it like an L's motor with an external prime can connected to the oil pressure gauge seeing that goes to the filter toping it off and to the valve cover squirter and the block which I'm assuming goes to the main bearings. Or should I just rotate the motor over for a few seconds without fuel so it won't start till the oil pump gets something into the engine at low starter cranking speeds. Or am I over thinking all if it?

[@MattVerley]

I usually rotate those engines over by hand several times before first start; not because of the oil system, but because of the injection pump. The rotor can stick and break the drive key. This is pretty common on the -002's and -003's that have ben sitting for long periods of time. With regards to the oil cannister, I wouldn't worry about filling it. It drains almost empty when the engine is shut off anyway. It usually takes a good 10 seconds for these engines to build oil pressure (unless you are starting it warm).

[@electromechanicalstuff2602]

Thanks. I did turn it over a few times by hand to check to see if the motor was seized up before checking to see if the starter worked. So hopefully all is good with fuel injection pump. Where do u usually get your parts from I need fuel pump screens and valve cover gasket. It only had one screed on the aux pump. So I put it on the first in series main pumps for now but would like to have all 3. I would also like to check valve lash hence the need for the gasket. This is my first military gen and hopefully not my last any other tips would be great. Thanks again.

[@electromechanicalstuff2602]

Bobby Diminnie update. got it running tonight about 9pm for the first time since i got it from govliq. I know its bad to idle the machine but for the first 30 seconds it sounded a bit knocky... and i really didnt want to ramp it up till it went away and it did. solid oil pressure gauge was pegged out. rotella 15-40. its about 15F here in MI but had the torpedo on it for a few hours while converting fuel filters in the closed garage. started checking out gauges. saw about 240v on volt gauge and saw 120v on one leg after flipping the leg selector switch. got the frequency gauge to 60hz after about 30 seconds from initial start. then all of a sudden the panel lights got real bright then dimmed back down a few times around the same time saw the frequency drop out and back again a few times. engine sounded stable and voltage was stable..ish... then lights stayed dim and the frequency gauge dropped out and stayed out. had to call the noise quits for tonight look deeper into it tomorrow and check to see if the batteries are charging properly. i gave a quick look at all the connections in the control box not a slightest sign of corrosion and everything looked tight but ill look closer tomorrow. is it possible i damaged anything by idling for the first 30 seconds? any suggestions on what else i can check. total run time maybe 5 minutes. didn't want to P.O. the neighbors too much P.s. I know you have 100 other posts and life activities going on but appreciate your time and any advise.

[@MattVerley]

It is true that you shouldn't allow the set to run at idle; leave the throttle set at 60 hz and allow it to come up to that RPM on startup. With that being said, I doubt that you damaged the VR card with only 30 seconds of low RPM operation. The panel lighting is based on the 24v system; the frequency and voltage meters are based on the 120v legs on the generator. The only thing that I can think of that would affect both of them is a bad ground on the control box. I believe that it is grounded on the stud labelled "ground" on the chassis (near the bottom of the set, close to the fuel pumps). I would clean that connection point, but also run a temporary ground from the negative terminal on the downstream battery to a bolt somewhere on the control cubicle. That's just my guess...let me know what you find out.

[@electromechanicalstuff2602]

sewerzuk I'm using optima batteries for this and I had to set them on the ground and install jumper cables to reach. I think the shoty connection was the culprit. I made some nice extended 00 cables at work and replaced the originals. I think the jumper cables I was using had a few bare spots and it would occasionally touch the frame. I started again and freq gauge held fine and lights stayed constant. Then I cleaned that ground anyways. New update. I borrowed a 5000 watt Garage heater to do some load testing. I used an amp clamp and its pulling about 21 amps @240 v but the percent load gauge is only reading about 75% . I tried adjusting the gauge screw but it just offsets 0% so when its off it reads 20%. Is there a way to adjust this down by the current transformer. I see a little pot by the convenience breaker what does that do? And what do the pots on the vr do? I added a toaster oven with only one of the two heating elements on, to L1 and a small 1gal air compressor to L3 to balance the load to about 25 amps per leg or 6000w/120%. I think this load can be obtained for about 30-40 mins. I keep reading everyone saying these things are good for 7500 watts so I gave it a try. Put the toaster oven on full blast 1000 watt rated with both elements on L1 and took off the air compressor and put a shop vac in its place on L3 along with the 5k heater the amp clamp read about 30 amps per leg 7200 watts and let it go. The load gauge still only said 105% About a minute or two in all of a sudden the gen started bogging down so I started shutting off loads starting with the shop vac still bogged then I shut off the oven still bogged had to shut off the main breaker to get the engine to recover. On full tilt the toaster oven doesn't turn on and off it just stays on. So the load never changed. So after the engine recovered I turned on the 5k heater only and noticed my multi meter read 130+ volt at the convince outlet. Even tho it was stable at 120 before the bog. I had to turn the v adjust all the way down to get 120 again. I have only the 5k heater on at this point and after 3 minutes the voltage dropped to about 110v and had to turn the v adjust back to the spot I had it before about half way to achieve 120v. I did all the loads again to check to see if the governor was going full tilt during the bog. When it bogged I checked and it was wide open throttle. Any reason as to why it gets this bog and voltage spike after an immediate over load removal and reset to the rated load. I did this again but this time I didn't change the v adjust I just let the heater take the over volt and sure enough without doing anything after 2 minutes it returned to the set 120 v. Am I just over loading this thing too much. I know I've read the loads are 110% for 1 hr 133%load for ten minutes. Is everyone just full of it when they say it can handle 7500+ watts. I stopped doing this after a few tries. And put it back to the 6000 watt load for about 30 minutes and the main breaker popped. Is this normal. I figure I heated the breaker up with the big loads and it needs some time to cool. What are your thoughts? Sorry for the book just want to give all the details.

[@tomschulte4996]

Very nice video and explanation. I am interested in going the other direction if possible. I have a Briggs and Stratton natural gas, whole house backup generator (18kW single phase) wired into an automatic transfer switch that feeds the main 200 amp panel. I just picked up an old Monarch 10ee lathe (1943) with 3 phase motor generator system that feeds a 3 hp DC spindle motor. So before I purchase a complete rotary phase converter to supply 3 phase to the lathe, I was hoping a phase converter control box may be able to be wired to utilize the standby generator. Any thoughts or comments are appreciated.

[@MattVerley]

+Tom Schulte There is really no way to get that 3rd "leg" for 3 phase from the single phase generator that you have (unless it happens to be a 12 lead generator head...unlikely given its size, but possible). Options for converting 120/240 to 120/208 3 phase are: A rotary phase converter (as you already mentioned), a static phase converter (has some disadvantages that you can probably look up on google) or a VFD (variable frequency drive; has some advantages, but will be a bit spendy).

[@tomschulte4996]

+sewerzuk Thanks for the reply. Later model 10ee's were outfitted with 5 hp DC motors. If you have Monarch refurbish your lathe, they now outfit it with a 7.5 hp ac motor driven by a VFD. Users indicate that static converters do not work well with these motors. Most guys replace electronics with a VFD and larger motor or a servo drive and motor with the 3 phase supplied by a rotary phase converter. Thanks again.

[@jschenkyou]

Just use a VFD. 100$ on Amazon. Then you can control your frequency.

[@DJtune10]

I have a 60kw diesel three phase generator. I only have 4 terminals. Three hot and neutral. I want to use this with a power distro that has three hots, neutral and ground. five cam-locks. can you explain how i can make this work?

[@PgPgDn]

Excellent and informative video! Thanks!

[@shamanking5195]

Hi how do you make sure your rotation has not changed when connecting the generator ???

[@azentioced9]

i have a genarator twin cylinder its 3 phase 4 wires coming out so do i just join up to any two of them and take an earth from the body of the engine? to have 240 or 220 volt?

[@MattVerley]

The 4 cables you see should be L1 L2 L3 and N. Between any two of the L terminals will get you 208v. Between any of the L and N cables will get you 120V. Assuming it is wired in Y configuration (this is the most common).

[@MrJeffParish]

Are the devices that would be 220v such as mig welders sensitive to the voltage variation? Is the circuitry inside them sensitive to the variation? I bought an old welding factory that has been gutted (all the wiring gone) It is essentially off grid now. Im tempted to leave it off grid. I do have equipment like welders and plasma cutters that i would like to run off my generator. what are your thoughts or any electricians in the comments? Very interesting to me. thanks for putting it together.

[@MattVerley]

if you look at the input voltage requirement for your tools, you'll find that most of them say 208v-240v. Almost all 240v tools and appliances work fine on 208v.

[@mannuel9165]

i need help how can i use my 220 3phase welder with 220 1phase? i already used a static converter and exploded the capacitor is there any solution?

[@zanmaynard2187]

I have a maginiss 3 phase generater but the voltage is 52 volt line to line what might be the problem

[@NobodyhearsU]

Wow, thanks for the great video! Subscribed! I have a question about the generator itself though. If I plan on running just two legs off of my 3 phase generator, the 3rd leg won't be doing anything..no shared loads...nothing. Is this bad for the generator? Balance issues etc.? Should I plug an electric heater into the third leg and just heat the outdoors? I'm all about that global warming! ;) Thanks!

[@MattVerley]

No, generally speaking there is no problem running an unbalanced load like that. The only real precaution is to make sure that current through any one phase doesn't exceed limitations for that leg. Obviously...you can't get 15kw of power through just one or two legs of a 3 phase 15kw generator because the single phase current will be much higher than the 3 phase current would at the same power level. In the MEP's case, it uses a shunt type breaker that uses a current transformer for current monitoring. So, you can't exceed phase current limits without tripping the main breaker. The real reason to switch a generator to single phase would be so that you can get the full rated power out of the generator, or if you needed 240/120v split phase instead of 208/120v.

[@jetkrazee]

Great video friend.Very informative. I have a question for you, I have a 3 phase generator that produces 380vac. Is it possible to use one leg and a really good ground to have usable 120vac single phase? It will be used in a remote area without any connection to a house ground or neutral. Thank you in advance for some pointers.

[@MattVerley]

Robert Tainio is that 380 phase to phase? so each leg is producing 190 volts? I would use a transformer to drop from 380v to 120/240

[@jetkrazee]

Ok, thank you.

[@snaremj]

Is there a way to get 240v on 2 legs without a transformer? I've got a 15kw 3ph generator, but I'm trying to figure out how to get it to single phase so I can hook it up to a conventional automatic transfer switch.

[@MattVerley]

I go over this in the video; but when the generator is configured for 3 phase 120/208, there is no way to get 120/240 single phase by using 2 legs of the 3 phase. You can manually turn the voltage up to 240v, but then each leg will be at about 136v; that's a little too hot to be feeding your house with. Most transfer switches and other 240v devices work just fine with 208, but if for some reason this doesn't work for you then most 12 wire generators can be converted to single phase 120/240. I have a video on how to do this step by step with an MEP-004a generator.

[@euromarinetrading737]

You state that the motors will be fine running at 208V and they could handle the extra current, but what about the wiring in the walls, can they handle the additional current? Same thing goes for the breakers, will they heat up and lead to pre-mature tripping? Or since the motor can handle 208V, that the current won't raised in the wires? Thanks

[@MattVerley]

The breakers are sized to prevent overloading the wiring associated with the circuit, so as long as the breakers are properly sized for the circuit the wiring and receptacles will always be OK. As long as you don't exceed the current rating for the circuit, the breaker won't trip. So to answer your question; yes, the breaker and wiring can handle the extra current. A synchronous motor running at 208v will draw more current than if it was running at 240v; but only by about 10%. So, a motor that draws 20 amps at 240v will run at about 22 amps at 208v. That is a very minimal increase...99.9% of the time, it won't make any difference. Since that motor is probably on a 30 amp circuit, the change from 20 amps to 22 amps is well within the current rating for that circuit. On the off chance that you are trying to run something that draws 20 amps on a 20 amp circuit, the change to 208v might start to cause "nuisance" trips.

[@uranium5694]

I would like to try the exact opposite. I would like to power a 3 phase house with a single phase portable generator. Is that possible?

[@MattVerley]

Not really; there are ways to get 3 phase power from a single phase input (static inverter, motor generator, etc.) but those are expensive solutions. A person is better off simply finding a 3 phase generator head. What kind of 3 phase loads does your house have? It is unusual for a residence to actually use 3 phase power; almost no consumer appliances use it.

[@bronjohnson2504]

is there a chance of damaging the generator by not using the third leg?

[@chanceheimann919]

How to you wire to get the 208 i dont understand each leg has 120 how do you connect then to get 208 ?

[@MattVerley]

Because the legs are 120 degrees out of phase, you don't just add 120+120 like you would in a split phase system (where the legs are 180 degrees out of phase). If you put a voltmeter between any two hot legs of a 120/208 wye 3 phase system, you'll get 208 volts. I explain this visually with an oscilloscope beginning at about 7:50 in the video.

[@bobocaterpillar3697]

wow! great video, thanks!

[@MrSehka77]

Can 120/ 208v 3 phase generator power a 230v 1 phase welder without modification has 4 prong 120/208v 20amp receptacle beside getting an adpator from 3 prong welder plug to 4 prong from generator?

[@robtana2526]

Is it single phase and 3 phase aswell?

[@ashforkdan]

The problem that I worry about is that when using a 3 phase only and taking only 120 volts from one leg,would it through it out of balance?Heating only one winding would give it a out of balance condition and end up destroying the generator.This is what I've been told.Is it true?

[@MattVerley]

It isn't a problem as long as you don't exceed the current limits for a single leg (this is why you're limited to about 2/3 of rated power). The tech manual even says that pulling single phase power is permissible, provided the current limits aren't exceeded. I've heard the "uneven heating" and "unbalanced load" myths too. These generators are designed to work this way! Other generators' instrumentation, control, protection, and excitation systems may not allow single phase operation; but with the MEP's it is just fine.

[@ashforkdan]

sewerzuk Big help.Thanks.I have a few of these mep's and will start using them for single legs now.What a relief.Keep up the good work.

[@L.J.7677]

I have a 45kw generac generator that I want to take it to my house is that possible because I was told that it would tear up the generator using a 3 phase on single phase house but it's a rather large house .

[@MattVerley]

+Lorenza Edwards It is possible to run your house on 2 of the 3 phases; you'll get 120/208 to your house that way, and only be able to use about 30kw of the generator's available output power. Most 3 phase generators tolerate this just fine, but without knowing exactly what you have I can't say for sure. As far as the 120/208 power to your house, most 240v appliances run just fine on 208v. Things like an electric oven, clothes dryer, hot water heater, electric heaters, etc. will produce less heat, but otherwise everything will work fine.

[@TheSoloAsylum]

Anything 240V will run on 208V. I have yet to see a problem with this ever. It will draw the extra amp or two but thats about it. Says me, a 20yr electrician.

[@MattVerley]

I agree...there are just a handful of motors that aren't rated for 208v, but the engineering margin takes care of that extra amp or two. I'm hesitant to say in the video "go for it, it will be just fine!" because there will be that 1 in 1000 guy who will find the motor that will burn up at 208v and argue with me about it!

[@TheSoloAsylum]

sewerzuk haha, good point. I am looking to buy an mep-2a now so I'll be back here with a question or two I'm sure. Thanks for the quality videos on these topics!

[@TheSoloAsylum]

twoheadedelvis You can grab any two legs from the 208V side as long as you dont have a high leg. Check each phase with a volt meter. If you get 120 on each you are good to go. A motor sees 208 and 240 as the same.

[@djscrizzle]

***** 240V 3ph High-Leg Delta will measure 120V, X to ground. 120V, Z to ground. And the orange/red (NEC mandates orange, old installs may be red) high leg wire will be 208 volts to ground. All phases will measure approx. 240V between each other. Realistically, the CNC machine could be wired up between any of the phases on either a 125/216V 3ph Y, or a 240V 3ph Hi-Leg Delta service and be just fine. In any case, before risking anything, consult the manufacturer first.

[@lorddiaboboss]

www.apc.com/shop/ca/en/products/Rack-PDU-Metered-Zero-U-57kW-208V-36C13--6C19/P-AP7864 How can I mod this for 240 or 480? I bought 2 for 100 bucks. Lol. Or should I make the power company give me 3phase?

[@sostahoe]

OK I have become more educated (slightly). I have a 125v 250v 50 amp single phase spider box. (CS6364). I have pics if needed. That also tells me I would NOT have 3 phase if using this outlet connector. Still looking for a potential solution for connections at the genset ?

[@MattVerley]

If you want to just hook up the spider box, you can wire it up to L1, L3, L0 (hot, hot, neutral). You will have 120/208 at the spider box, but as previously discussed that will be just fine 99% of the time...

[@djscrizzle]

sewerzuk That's precisely how we hook up single phase distro boxes in the entertainment industry to the company switch/Bullswitch, in order to power large sound, light, and video systems. There are 3 phase CS twistlocks out there, the CS8360 series. They carry 3 hots and ground, 3P,4W. If you need 4 pole, 5 wire 3PhY, look at NEMA L21-20 and L21-30. Or use Camloks for higher capacity loads.

[@XER239]

so in single phase , a 803a only puts out 7kw and a 804a only 10kw at 208 volts?

[@rich1879]

Man o man you helped me out,,,thank you so much.

[@NTF-zb9wi]

I've done all of my own 110 & 220 electrical work for decades; but, when it comes to 3-phase, I'm a total noobey... I learned quite a lot from your video; but, since your example was a military generator, which had a "Line 0," I'm still left with a lot of questions. I'm going to be rewiring some stator/rotor "smart drive" motors, which I've scavenged out of "dead" washing machines. (Typically, because the control board went bad & started throwing error codes. Out of 6 motors, the stators have tested good in 5. That one was probably good until a FedEx driver mistook the package for a discus...) The process for converting these from being motors to being generators involves some major snipping and soldering, leaving you with 3 wires (made out of jumper cables - #8? #6? wire,) not 4... How would someone wind up with a "Line 0" on something like this? Would it just be the (lighter gauge) grounding wire? 3 of the 6 were picked up used on ebay; the other 3 cost me $10/ea. for the entire washing machine; but, still, I hate to waste any of them; esp., on my marginal budget & having that one already damaged by that FedEx driver. I don't remember how many stator coils are on the damaged stator; but, regardless of the total number, that number is always divisible by 3... IF I can isolate the damaged coil(s?) on that one; and, be left with a number of good coils which is divisible by either 2 or 4, might it be able to be rewired for either 110 or 220 single phase? If you don't know, perhaps someone who has tinkered with these type of motors, such as to use them on a vertical axis wind turbine might just know; &, I'd welcome their input, as well... :)

[@MattVerley]

L0 is the center of the “wye.” It wouldn’t exist in a generator configured for delta 3 phase. It is at zero potential; so from any of the hot legs to L0 you get 120v.

[@NTF-zb9wi]

@@MattVerley So, if I rewire it for wye-type 3-phase, I'd wind up with 3 hot 120v "legs" and the equivalent of a neutral? (I'm trying to learn all of this from scratch ~ at 67, with brain fog whenever I push myself too hard... Difficult; but, better than any of the foreseeable alternatives...) The "save" button isn't showing up; &, the scroll bar won't let me scroll down to find it!

[@Rob-kw4kx]

Load balancing I feel would be the only issue. You can't just run two legs without considering the neutral.

[@staym925]

That's what I was thinking, although, use a autotransformer and get your neutral.

[@miketheherbguy]

have you heard of using a 3 phase electric motor for the generator and power all in one? first get it started on one leg, then rob the other two for power once its running. i heard that at a bar a long time ago. think its possible? seems like it should.

[@MattVerley]

miketheherbguy Yep; that is called a rotary phase converter. I built my own 30HP one a few years ago; this is how I currently power my milling machine and lathe

[@miketheherbguy]

sewerzuk did you do a vid on that, currently have a dead shop right now until that is done. what is your email. would love to talk to you about this.

[@MattVerley]

No, I did not put together a video on the phase converter. I will send you a message with my email address

[@miketheherbguy]

want to do a detailed video on it.?

[@krakenwoodfloorservicemcma5975]

Awesome video.. smart kid.

[@shnobi24]

how would you connect the wires to backup a house running 3 phase. from the generator to the house?

[@MattVerley]

You just connect any two of the generators hot legs (L1, L2, or L3) to the two hot legs in the breaker box and then connect the generator's neutral to the breaker box's neutral. That is the GENERAL idea. Local electrical codes may dictate exactly how you do that, whether grounds and neutrals are cross connected, type of disconnect switch used, etc.

[@shnobi24]

sewerzuk thanks for the answer by doing that you will be sending 3 phase to a house?

[@MattVerley]

shnobi24 No, the 3rd phase from the generator is not used. When you hook it up as I described, you are sending split phase to the house which is basically the same as what you get from the power company.

[@shnobi24]

sewerzuk thanks, but like you say you only use 2/3 of the useable power.

[@vivekbhaskar7238]

Awesome video!!

[@randydunning6729]

How did you get around the 400hz to 60hz ?

[@MattVerley]

I didn't buy any 400hz sets, except for engine parts.

[@thomasjefferson5727]

Your graph is mirrored across the x axis...? Meaning you would have no voltage if you pulled from either leg. You're 240 graph is going to look the same with greater amplitude.

[@MattVerley]

Not quite; if you pull from one leg and neutral you have 120v. If you pull from both legs you get 240v because each leg is 180 degrees out of phase with the other leg.

[@phooesnax]

Great job!

[@mannuel9165]

how can i use 220 three phase welder with 220 single phase

[@crashk6]

Phase converter. There are rotary phase converters, which as the name implies are electromechanical devices, and can actually be built from a three phase motor, a few capacitors, and a smattering of electronic components & switches. There are also solid state phase converters, which are more efficient then rotary, but also more expensive to purchase.

[@thomasjefferson5727]

220 3 phase is not a thing. Nor is 220 single phase.

[@andrewrojas5614]

Hi Matt. I have to find a way to charge two electric trucks that need 3 phase /50Amps. 204V. Where I pive ther eos only regular phase. Can I have your email so I can send you what I have .. and maybe you can help me out? Tha ks

[@MattVerley]

There are a number of ways to generate 3 phase from single phase...but at that power level really the only economical way is with a rotary phase converter. However, this really won't suit your needs well. Depending on the chargers on the electric trucks, there is a small chance they might be OK with a single phase input (there's no way I can guarantee this without part numbers and/or schematics). I hate to say it...but my guess is that you're going to be stuck finding actual 3 phase power, or changing the charging circuitry on the electric trucks.

[@elliottmanning]

Why not just add or replace with a three phase electrical panel and pull in a "C" phase cable??? Use a same brand of electrical panel and you could use the same type of breakers. Then balance out your loads over the three phases and still have three phase power for your special shop power equipment. Just saying this might be a whole lot simpler in the long run...

[@MattVerley]

+Elliott Manning Adding a new panel is beyond the capability of the average generator user, I think. The idea behind this video is a quick and simple plug and play type emergency setup. But, you are right. You can get more power out of the generator if you balance single phase loads across the 3 phases...

[@bangbadroes932]

5 kw. ..3 phase generator to singel phase please for diagram. ......tanks

[@patientman777]

Matt, do you share your email address? I have questions about an MEP 805 B.