Dr. Jones Posted September 29, 2008 Share Posted September 29, 2008 My next project will be making a sub panel from my dryer outletlike this? Attached files Link to comment Share on other sites More sharing options...
Videoguy84 Posted September 29, 2008 Share Posted September 29, 2008 bossgroove that looks almost exactly like the relay I used. Except mine did not take 120 volts directly to control the relay but instead wanted low voltage DC, so I simply wired in a 'wall-wart' type transformer to control the relay via 120 AC. The relay was rated 10A at 240 volts, major overkill for what I was doing with it, but it was all I had on hand so what the heck. Link to comment Share on other sites More sharing options...
Donald Puryear Posted September 29, 2008 Share Posted September 29, 2008 bossgroove wrote: My machine has three. I'm not to electronically intelligent, but I have put simple electronics together. I'm lost at n/o. My next project will be making a sub panel from my dryer outlet."n/o" Refers to the contacts that are open till the relay is energized. That relay will work, but i would wire a C9 on the same circuit. I use solid state relays . I will try to send a pic tomorrow Link to comment Share on other sites More sharing options...
Donald Puryear Posted September 29, 2008 Share Posted September 29, 2008 Dr. Jones wrote: My next project will be making a sub panel from my dryer outletlike this?Be carefull, It's not safe to tap your dryer plug if it has only 3wires. The older dryer recpt. had only 3 wires (hot,grnd,hot). the new dryer recpt. have 4 wires (hot,neut,grnd,hot). You need the fourth wire to be safe. Link to comment Share on other sites More sharing options...
bossgroove Posted September 30, 2008 Share Posted September 30, 2008 I have four prongs. Thanks a bunch Link to comment Share on other sites More sharing options...
Dr. Jones Posted September 30, 2008 Share Posted September 30, 2008 Donald Puryear wrote: Dr. Jones wrote: My next project will be making a sub panel from my dryer outletlike this?Be carefull, It's not safe to tap your dryer plug if it has only 3wires. The older dryer recpt. had only 3 wires (hot,grnd,hot). the new dryer recpt. have 4 wires (hot,neut,grnd,hot). You need the fourth wire to be safe. not necessarilyA 208V 3phase unit only uses 2 hots and a ground. If you use a 3 wire plug, you need to balance the phases. The closer to each other they are the better. The difference in amperage then is transfered down the ground.As a force of habit, I balance all my loads - to many years of working with gennies Link to comment Share on other sites More sharing options...
Donald Puryear Posted September 30, 2008 Share Posted September 30, 2008 Dr. JonesI hate to fuss butt, a A 208V 3phase unit would use a 4 wire Cable containing 3 HOT's and one ground. The ground is never designed to carry any current except in a fault condition. The neutral or White wire is used as a return path for the unbalanced load. In all new installations a dryer Recpt. should have 1 red, 1 black, 1 White, and one bare or green wire. If you were to build a sub panel to plug into a that recpt. you would want to keep the neutrals (white wires) and ground (green or bare wires) separate and bond the ground to the metal can to protect you against shorts to the can. Link to comment Share on other sites More sharing options...
FBW4 Posted October 6, 2008 Share Posted October 6, 2008 You are using phase wrong.... Those are single phase 2 pole. Link to comment Share on other sites More sharing options...
Dr. Jones Posted October 7, 2008 Share Posted October 7, 2008 Donald Puryear wrote: Dr. JonesI hate to fuss butt, a A 208V 3phase unit would use a 4 wire Cable containing 3 HOT's and one ground. The ground is never designed to carry any current except in a fault condition. The neutral or White wire is used as a return path for the unbalanced load. In all new installations a dryer Recpt. should have 1 red, 1 black, 1 White, and one bare or green wire. If you were to build a sub panel to plug into a that recpt. you would want to keep the neutrals (white wires) and ground (green or bare wires) separate and bond the ground to the metal can to protect you against shorts to the can.DonaldExplain an L6-20? it is 2hots and one ground - the two hot legs are balanced resulting in a minimal current returning down the ground208v is 2 120v legs of a 3phase system 120* out of phase.The same can be true for the dryer plug with three wires. The two hot legs need to be balanced to ensure minimal current traveling on the ground leg. (side note- I would discourage anyone not comfortable with power to leave it to the professionals)A typical 3phase wire ( at least in my field) is 5 wire, the ground and neutral are supplied from the source - generally the transformer or gennie Link to comment Share on other sites More sharing options...
Donald Puryear Posted October 7, 2008 Share Posted October 7, 2008 DR. JONES:an L6-20 is a locking receptacle designed for 20a 240v equipment. The equipment uses 2 hot wires (240v) and a ground. In the electrical world the ground conductor is not designed to carry any current under normal circumstanses. The ground conductor is designed to carry the fault current. (ie. a short to ground or the metal case) If the appliance needs a conductor to carry the unbalanced load it would have a 4 wire cable and the neutral would carry the unbalanced load. At one time the NEC code had an exception that would allow you to use the ground to carry the unbalanced load (110v light) on Dryers & Ranges. This was changed @ 1992 requiring the use of 4 wire cords on dryers and ranges.You are 100% correct about 5 wires on a 3 phase system. Must units that I hook up that are 3 phase do not require a neutral. Its nice to know there are people out here willing to help others. To change the subject: Do you GFCI protect all your lighting wiring? Link to comment Share on other sites More sharing options...
Dr. Jones Posted October 8, 2008 Share Posted October 8, 2008 To change the subject: Do you GFCI protect all your lighting wiring?At work - yes everything is on a 15A gfi'd breakerat home - everything a viewer might be able to touch- yes - the roof, eaves, etc that are not readilly accessible - are not ( it is low voltage led's on the eaves)plus - I don't regularly run the show in the rain ( unless I'm sitting outside programming)Must units that I hook up that are 3 phase do not require a neutral dealing with mostly 4/0 cam, 2/0 banded, and pin &sleeve - I rarely use less than 4 wires - equipment hates ground loops- so almost all grounding is done at the source - only 4/w i use is pre transformer (generally 460v)usually the only code I am interested in are sect. 590, 520, 518, 525, and 530 - can you guess what line of work i'm in? Link to comment Share on other sites More sharing options...
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