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My 220V outlet is a 3-wire "dryer" style outlet with no neutral. The Harvey manual doesn't indicate which type of plug it uses or if it needs a neutral connection (for some type of internal 110V circuitry). Can anyone with one of those units let me know what kind of cord it uses? Is it 4-wire or 3-wire?
Going to reply to my own post here- another forum indicates that it's a Nema 6-20 plug, which is a 3-wire connection. I should be good to go with just swapping out the plug.
Depends. Are you in North America?
Bill D
Yes, but why does that matter? I can't imagine they'd wire it differently for different markets. Their electrical schematic only lists 3 lines for input power- earth, line, and neutral. In the US you just have two hot lines. For single phase 220 you'd have a line and neutral, but from the point of view of the controller it doesn't matter.
The forum for their parent company here: https://harveyindustriesintl.com/com...ust-collector/
lists the plug as a NEMA 6-20P which doesn't have a neutral connector.
Location wouldn't make a difference. Usually a piece of machinery that has a large 240V motor or heating load only needs the neutral for the control circuit. They can save a (very) few dollars by not putting in a 120V control transformer.Quote:
Originally Posted by Bert McMahan
A 3-wire dryer receptacle (NEMA 10-30R) does not have a ground, if anyone takes the time to look at the rating usually embossed on the face of the receptacle which is 30A 125/250V which means it is a 30 ampere, dual voltage non grounding device, there is no ground, it was made only for clothes dryers where prior to the adoption of the 1996 NEC, it was permitted to ground the frame of clothes dryers to the neutral of the appliance, if it was a grounding conductor used as a neutral a practice never permitted by code, since a dryer element is 240V, but the motor & controls, & light if present are 120V, a neutral is required. A 3-wire dryer is only code compliant when used for a dryer.
That was a completely screwball loophole that never, thankfully, made it into Canadian code. I mean really, it's decidedQuote:
Originally Posted by Rollie Meyers
that they can make a better, safer system by separating the neutral and ground conductors after the service box. But no, let's just connect 'em right back together To the dryer put the whole installation back into the '50s
For washers they included a ground clamp to be tied to the supply faucet. I feel that is actually safer then tieing it to some ground rod far away from the puddle of water you are standing in. That ground rod is likely also several feet different in altitude, hence potential voltages exist.
Bill D
You can feel that way all you like, but there are countless experts in electrical code & safety that disagree with you. There are any number of scenarios, not directly related to electrical, where that ground connection from the faucet could be interrupted. A bonding conductor that is part of an approved cable assembly that is installed per code & inspected has been determined to be the safest way. Do you really want electrical installations to be done according to how each person thinks is best?Quote:
Originally Posted by Bill Dufour
Many pitfalls with that including proper bonding with the electrical system and actual use of conductive pipe end to end...something that's disappearing from home builds and renovations in favor of PEX, etc. The best solution is always a proper ground IN the electrical circuit to the device. There was a time "back in the day" that a lot of things like this were common. No longer and code reflects that.Quote:
Originally Posted by Bill Dufour
Not all plumbing is conductive. A grounding rod is a known quantity.
Quote:
Originally Posted by Rollie Meyers
Unfortunately I didn't catch that my electrician ran 2 hots and a ground to my 220 V plugs in time (he finished about 4 months ago), and apparently neither did the guy from codes. He's got it wired with two hots and a ground back to the panel. No neutral. From a bit of Googling, it looks like the 10-30 is supposed to be hot-hot-neutral, but the 6-30R or L6-30R is hot-hot-ground. It's either that, or try to get the electrician to rerun a bunch of cables. Who knows how much that would run me... I bet he saved dozens of dollars out of my expensive shop build to not run the extra 30 feet of cable :mad:
Is it run to a sub, or the main panel?
They're bonded at the main anyway.
Bert, that would be normal for 240v machine circuits that do not need simultaneous 120v power to the same device. Dual voltage devices (other than the exception that Rollie mentioned) do require four wire circuits. My CNC machine is an example and uses an L14-30 for the machine to circuit connection. If you were to be forced to use a four wire circuit for a 240v only machine, the neutral would go unused anyway as the machine has no connection for it.
Thanks for the comfort Jim. I'm sure it'll be fine, but since there's a subpanel literally in the same room as the circuits he ran the cost difference would've been minimal and would have given me some flexibility down the line. I totally understand the intermittent need for neutral, having worked on machines that have both, and I'd have preferred it be there just in case. Luckily the Harvey and my CU300 are both 220V only, but I could see adding a CNC or something that needed some 120V control circuitry one day.