peylas Posted September 21, 2019 Share Posted September 21, 2019 I have a single phase single volt (UK 220-240) 1Hp electric motor with two capacitors, start and run. As photographed. This is to run my Milling machine. I need to connect the motor, via appropriate switch gear, to mains AC. I appreciate the earth wire connects to the "seventh" terminal at the side. But I have no idea where the Live and Neutral wires need to connect. I appreciate that the metal strips (as photographed, shown between U1/W2 and V1/U2) manage the rotation, and presently are connected for forward/clockwise rotation, and can be changed to U1/V1 and W2/U2 for reverse/counter-clockwise rotation (which I will probably use). But for either scenario (CW or CCW), to which of the terminals should the Live and Neutral AC wires be connected? If someone could offer a clear answer please - in terms of U1 etc as per photograph - as I've scoured the internet and have fried my brain looking at too many conflicting options (mostly involving 3phase despite specific search criteria). Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted September 21, 2019 Share Posted September 21, 2019 Welcome to IFI... I always suggest reading this to get the best out of the forum. READ THIS FIRST I guess from the title, you are somewhere in the UK. If you edit your profile to show your location we won't have to guess and you may be surprised how many members are near enough to visit and give you a hand. We have some very qualified members to offer electrical advice here in the US but don't know if that would help where you are. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 21, 2019 Share Posted September 21, 2019 the schematic clearly shows U1/W2 and V1/U2 to make the connections, but I fear a person that cant understand that, may be in over their heads installing this Quote Link to comment Share on other sites More sharing options...
peylas Posted September 23, 2019 Author Share Posted September 23, 2019 On 9/21/2019 at 7:17 PM, Steve Sells said: the schematic clearly shows U1/W2 and V1/U2 to make the connections, but I fear a person that cant understand that, may be in over their heads installing this Dear Sir, Thank you for your help with my enquiry. I was obviously under the misconception that IFI was a forum for all: novices, experienced persons, and experts alike. And whilst I may have many decades experience in various crafting fields, including mechanics, metalwork, computing and so forth, elec-trickery continues to elude me. Combined with the varying and often contradictory advice given on the web, I thought I would seek help from a forum such as this, rather than destroy a not inexpensive new motor. However, I realise my mistake if this is a forum for people who should already know the answer to their own question, and as I had not appreciated that arrogance was another requisite, then I am certainly in over my head, and respectfully withdraw my enquiry and registration. Have a nice day. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 23, 2019 Share Posted September 23, 2019 I am a Master Electrician and have been in the trade about 35 years. and if you think a warning about safety is arrogance, then YOU sir are the one suffering from delusions. I am more worried about your killing yourself or someone else. This is a forum for many types, of many age groups and knowledge levels. Not all are capable to safely work with electricity, I am also a Medic and I have seen what faulty wiring can do to a body. So knock it off rather than looking for a fight when you were asking for free help. You have an interesting way of saying "thank you Mr Sells for saving me over $100 with`your free assistance" as well Quote Link to comment Share on other sites More sharing options...
JHCC Posted September 23, 2019 Share Posted September 23, 2019 As a frequent beneficiary of Steve's free advice (both blacksmithing-related and for the wiring in my own home), I would like to take the opportunity to thank him publicly for making it available so readily and generously. Don't mistake his well-earned self-confidence for arrogance. Quote Link to comment Share on other sites More sharing options...
Latticino Posted September 23, 2019 Share Posted September 23, 2019 I think part of the issue here has to do with varying terminology between British and American colloquial English. I still tend to use the wrong terminology for electrical connections, though I have successfully wired several shops, and Steve has been kind enough to correct me regarding this in the past (two pole, single phase always messes me up, since the standard nomenclature is non-intuitive for me) Here in the US I think if you say you are connecting wiring to the "mains" it means that you are tying in prior to a circuit breaker. This is quite a dangerous prospect and definitely not recommended. I suspect you mean something different. If this were my project, I would wire up a 220/240 V outlet in the proximity of the milling machine with (3) wires from an appropriately sized dual pole circuit breaker with wires selected to carry the anticipated inrush current at startup for the distance the wire has to run. Two hot poles and one neutral/ground (needless to say with the breaker main circuit switched off). Then I would wire a cord to the motor with a matching plug that would bring power to the U1 and U2 terminals on the motor. I would wire the neutral/ground to the screw connection just to the left of the terminal block in your photo. I'm not sure if the latter is technically required for correct operation (though I'm sure Steve could elaborate), but I'm a fan of properly grounding my equipment, especially if I'm going to be touching it during operation. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 23, 2019 Share Posted September 23, 2019 Neutral and ground are not the same thing, Ground/Earth connects to a ground rod, and a neutral connects to the center tap or opposing side of transformer(s) we do not connect a neutral to the motor case frame Quote Link to comment Share on other sites More sharing options...
Latticino Posted September 23, 2019 Share Posted September 23, 2019 Steve, Interesting, I knew you would have more to teach me. If I recall correctly all the neutrals in my circuit breaker panels connected to a perimeter terminal strip with some unshielded wire that appears to be tied to ground. I'd post a picture, but I"m afraid you would laugh at my hodge-podge wiring routing. I'll check it out again and confer with the electrical engineer in our office to confirm whether I've made a wiring mistake. Probably just using the wrong terminology again. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 23, 2019 Share Posted September 23, 2019 At the main point of entry <main panel> only: the neutrals and grounds are bonded, until that point they are kept separate to avoid electrocution but that is a long story to explain the hows and whys (another reason why the apprenticeship is 5 years long for electrical trade) Short version the neutral carries the imbalance of the load, and ground drains stray voltage, also insuring a trip if the power feeds short to the frame. If the frame were not grounded, a shorted feeder would energize the case, and stay that way (potential) until some poor soul makes contact, completing the circuit to ground and possibly getting them killed. Using a neutral for that case ground could in theory also allow the case to be energized and not trip the breaker. leaving a dangerous situation like I just described Quote Link to comment Share on other sites More sharing options...
Anachronist58 Posted September 23, 2019 Share Posted September 23, 2019 Long story indeed. Even installing a sub panel can get us killed, correct Mr. Sells? Quote Link to comment Share on other sites More sharing options...
Steve Shimanek Posted September 23, 2019 Share Posted September 23, 2019 When I first read Steve Sell's response, I thought it accurate but potentially abrupt to the point of potential rudeness; after studying his response for some time, i realized that the way he put the matter was entirely correct and actually showed concern for the OP. Well done. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 23, 2019 Share Posted September 23, 2019 Since he could not understand that 'SUPPLY' meant to connect power supply at that point I wanted to be clear in my response to avoid more confusion. This is a world wide forum and he only stated UK power, English may not be his first language either, explaining his misuse of terms, I don't speak Welsh, Hindi or Gaelic and can only imagine how my words would come across if I tried Quote Link to comment Share on other sites More sharing options...
Dale Russell Posted September 23, 2019 Share Posted September 23, 2019 My 2 cent's worth ..... If in doubt call a " Licenced Electrician " to wire it up to " your " countries wiring code . Dale Russell Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted September 24, 2019 Share Posted September 24, 2019 That is the best suggestion, although the OP doesn't take suggestions very seriously. We still don't know where he is located. BTW: I've always wondered, if you give your 2 cent's worth and they only give you a penny for your thought's, who gets the extra penny? Quote Link to comment Share on other sites More sharing options...
JHCC Posted September 24, 2019 Share Posted September 24, 2019 Fortunately, knowledge is not diminished by being shared. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted September 24, 2019 Share Posted September 24, 2019 14 hours ago, Irondragon Forge & Clay said: ... if you give your 2 cent's worth and they only give you a penny for your thought's, who gets the extra penny? Goes to taxes Quote Link to comment Share on other sites More sharing options...
BIGGUNDOCTOR Posted September 24, 2019 Share Posted September 24, 2019 There was a movie around the partial pennies in paychecks.... Quote Link to comment Share on other sites More sharing options...
Frosty Posted September 24, 2019 Share Posted September 24, 2019 37 minutes ago, BIGGUNDOCTOR said: There was a movie around the partial pennies in paychecks.... I remember that one! An accountant kept seeing fractions of a penny dropped from payments and decided he could collect them and nobody would notice. Didn't work out as planned though. Good comedy McGuffin though. Superman movie? All I can say about or to the OP is. If straight talk is too much then asking blacksmiths for free advice isn't a good idea. Getting snitty when a master electrician GIFTS you with free advice is poor PR. Hire an electrician or just take your motor to a shop and ask to have the cord wired. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
pnut Posted September 24, 2019 Share Posted September 24, 2019 Office space Pnut Quote Link to comment Share on other sites More sharing options...
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