Exactly, thanks for the good explanation John. JT
On 12/26/2015 5:18 PM, John Kasunich wrote: > > On Sat, Dec 26, 2015, at 06:02 PM, Bertho Stultiens wrote: >> On 12/26/2015 11:53 PM, John Thornton wrote: >>>>> Yes, that was my plan to run everything off of 120v except the VFD. >>>> However, your drawing shows the VFD to be on the 120V side. >>>> >>>> I am a bit confused now which is on what and where. >>> Ah the two 120v lines without a neutral is 240v, sorry if my drawing is >>> confusing. That's why I labeled them L1 and L2 instead of L1 and N. >> Are you using two phases (L1 + L2) of a three phase system or are you >> actually using a one-phase system (L1 + N). >> >> There is quite a big difference between the two scenarios. >> >> The voltage between any two phases in a three phase system is sqrt(3) >> times the voltage between neutral and any single phase. >> > I believe the answer is "neither". > > I think he's using the American standard 120/240V split single phase system. > The distribution transformer has a 240V single phase secondary with a center > tap. The tap is grounded, and is the Neutral. The two ends are L1 and L2. > > 120V volt loads (all "ordinary" residential loads such as lights and small > appliances) are connected between either L1 or L2 and Neutral. The > panels are designed so that roughly half the total load is on each side. > > 240V loads (electric stoves, electric dryers, central air conditioners) are > connected from L1 to L2. Sometimes there is a neutral (for modest 120V > loads), sometimes there isn't. This drawing shows some of the plugs > that are used: > > https://en.wikipedia.org/wiki/NEMA_plug#/media/File:NEMA_simplified_pins.svg > > The 120/240V split single phase system is the norm for American residential > power. Three phase in a residence is extremely uncommon. > > > > > John Kasunich > jmkasun...@fastmail.fm > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
