problem with new (used) band saw

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On Sun, 14 Jun 2009 09:03:22 -0400, "J. Clarke"

Local Jurisdiction rules? I know the codes here certainly don't require an unnecessary, unusable wire in a straight 240v circuit equipped with NEMA 6-XX receptacles. Circuits for ranges, dryers and other such loads that use 240v and 120v simultaneously are 4-wire circuits (2 hot, neutral and ground) with NEMA14-XX wiring devices, but that's because of the need for the circuit to supply 120v as well as 240v.
In those jurisdictions that require a neutral for a straight 240v circuit, what is done with the neutral wire? NEMA 6-XX devices don't have a provision for a third conductor so there's nowhere to connect it unless it's tied to the boxes and used as a duplicate grounding conductor. Or do all 240v plug-in loads have to be fitted with a NEMA 14 plug with the neutral connection left vacant?
Tom Veatch Wichita, KS USA
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"Jim" wrote:

The green wire is NEVER neutral, it is ALWAYS earth ground, period end of report.
Lew
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In the US (Europe is quite different):

Not always hot, though it is always *a* hot (it may be switched).

No! Green is ground. Ground and neutral are different animals.

Yes. If there is a neutral in 240V cords it is also white.

In *240V* (split-phase - US style) cords the second hot it is usually red, but I believe it can be anything other than green or white. (Blue is commonly used for the third phase in 3-phase).

In a 240V circuit you may "paint" the white wire black (or red) to indicate that it is a hot. It's done for the "traveling" wires in 120V 3-way circuits, as well.

Absolutely not! It most certainly is *NOT* neutral. The green wire *MUST* be ground. Ground and neutral are different. 220V circuits may or may not have a neutral.

He sure as hell shouldn't listen to you. If you don't know what you're doing, please don't give advice. You could get someone killed!
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On Sat, 13 Jun 2009 12:24:34 -0700 (PDT), bob

I have a Baldor 3HP motor on my bandsaw but there seems to be a difference between your diagram and mine. To switch mine from High to Low is was only necessary to disconnect 3 from the 2-3-5 bundle and connect it to the 1-8 pair. Then connect J to the 2-5 pair replacing the 3 that was removed from that bundle. J is capped off and not used in the High voltage configuration of my motor.
There's a bigger difference between the diagram for your motor and mine than I'd expect for similar type motors (albeit different HP) from the same company. Can you post a picture of your diagram in ABPW?
My diagram:
High:
1----|_______Line 1 8----|
2----| 3----| 5----|
4--------------- Line 2
J------ (unused)
Low:
1------| 3------|----------Line 1 8------|
2------| 5------| J------|
4-----------------Line 2
Tom Veatch Wichita, KS USA
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Both connections are actually correct and accomplish the same thing. Wire #4 goes through a thermal overload before it goes to the main motor winding. Wire #J comes off of the overload to be used as the means for connecting the two main windings in parallel when connected for low (115) volts.
The starting winding in this motor is always 115 volts. When the motor is connected for 230 volts, the two halves of the main winding are connected in series so that they each see 115 volts. The 2/3/8 (or 2/3/5) connection is the mid point of the series connection, which allows the starting winding to receive 115 volts from the 230 volt connection. Thus, the other end of the starting winding (#5 or #8) can be connected to either the #1/line connection, or be connected to wire #J. Either way, interchanging #5 and #8 will reverse the motor rotation.
Doug
wrote:

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wrote:

Thanks, Doug. Without knowing what's on the other end of the leads, it's not easy to see that the two schemes are equivalent.
Tom Veatch Wichita, KS USA
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Your connections are correct. Does the motor hum or buzz when you try to start it, or is it completely dead? If it's completely dead, and you definitely have power going to the motor leads, then the manual motor protector is probably tripped. There should be a red button somewhere on the motor. You need to press it in firmly until it clicks.
If the motor hums, then there is a problem with the starting circuit - either a bad capacitor or a bad internal starting switch (very common on woodworking motors). Try this: remove the belt, install a jumper wire across the two wires going to the capacitor. Try starting the motor. If it starts, you need a new capacitor. If it still hums, you need a new internal starting switch.
Doug
I recently bought a used Rockwell bandsaw, which had been refitted with a Baldor 1 hp motor, that was set up to run on 220V. I was told that I could rewire it to run on 110V, which is all I have in my garage. The saw ran on 220v when I tested it just fine.
So, I dutifully tried to make the change, but now it does not run. Im hoping someone can tell me my mistake.
Heres what I did: The motor had 2 schematics on it, for low voltage and one for high voltage. The high voltage schematic showed this: wires #2/3/5 together; wire #1 alone (which I found to be connected to the cords brown wire also); wire #4 to line (I found #4 to be connected to the cords black wire); wires #J/8 together. This is, in fact, how it was wired when I opened it up.
The second schematic showed this: wires #1/3/5 together (which I left also connected to the cords brown wire); wire #4 to line (which I left connected to the cords black wire); wires #2/J/8 together. I reconnected things following this schematic (in other words, I moved #2 from 2/3/5 to J/8 and connected 1/brown to 3/5; I left 4/black alone).
[As a sidenote, the motor also indicated that to reverse rotation interchange #5 and #8since #s 5 and 8 had been switched in the existing wiring I found, and therefore rotation had already been reversed, I also treated #5 as #8including all of the descriptions above, where Ive already substituted 5 for 8]
Then, I switched the male plug. The 220V plug had green, black, and brown wires going to it; green connected to G, black connected to Y, and brown connected to X. I put on a new 110V plug and connected the green to the green screw, the black to the brass screw, and the brown to the silver screw.
It does not turn on now. Please help! I really appreciate it. I dont have much money and really need to get this working
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If it was set up to run on 220VAC, It may have only needed two wires - both hot.
If I were you, I would put it back the way I found it, test it to be sure you have, and begin again.
This time, ignore the rotation - it should NOT affect the wiring as to voltage.
Ignore the "colors" on the existing power cord - most 220 cords will be RED BLACK and WHITE with the first two the essential HOTS and the last the NEUTRAL. The one on your motor appears to have BROWN where I expected RED and GREEN where I expected WHITE.
The X and Y on the plug are not at all familiar - are you in the USofA? But the left and right pins should be the HOTS and the one in the center, the NEUTRAL What was the green wire tied to when you opened it up?
For the 120VAC there will only be one HOT (BLACK) , one NEUTRAL (WHITE) and one GROUND (GREEN) if you use the appropriate colored cord. The green would attach to a grounding screw on the motor frame and the black to the LINE. But I can't tell how to connect the white.
You might also look for Baldor web site and wiring diagrams/ information there. Without the diagrams to look at, I'm hard pressed to really help.
http://www.baldor.com/support /
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On Wed, 17 Jun 2009 20:27:10 -0700 (PDT), Hoosierpopi

If you're talking about the power cord, it will only have a neutral if the appliance requires 120v as well as 240v - such as a range or drier. A 240v tool such as a bandsaw rarely, if ever, requires 120v simultaneously with the 240v. As such it will have only 3 wires in the power card, the two "hots"and ground. Older installations of range and drier connections were allowed to use the ground wire as the neutral but the NEC prohibits that in new installations.

No. The "center" pin on NEMA 6 (250v two pole three wire grounding) plugs and receptacles is for the ground wire (green/bare). There is no neutral. The X and Y (and Z, for 3-phase) designation is standard terminology in the NEMA configurations for the line connections.
Incidentally, the OP found his problem in the bandsaw's on/off switch.
Tom Veatch Wichita, KS USA
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Tom Veatch wrote: ...

Actually, bandsaws and drill presses that had/have built-in work lamps that do precisely the split voltage thing are fairly common ime (I have one of each, in fact)...
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Don't have a bandsaw /w light, but do have a drill press with a dual voltage motor and a work light. With the DP, to run the motor with 240, the light with 120, and meet the NEC requirement of no current in the grounding conductor in normal operation, the "chassis" of the DP would have to be rewired. It has a 3-wire (2+G) power cord and no provision in the chassis wiring for a neutral. The manual for the DP had a wiring diagram for 240v operation showing the light connected between one of the lines and the ground wire. Since I've been unable to find a 240v bulb that will fit in the light cavity, that's how I have it connected. Does it or does it not meet NEC requirements? The question is moot since the DP is a "temporary" plugin load and isn't covered by the NEC. If it were hardwired, and the inspector understood the situation, I'm sure it would be red-tagged.
If the NEC doesn't apply, would the UL list the DP in that configuration? I suspect it would not since that diagram has been removed from the current versions of the manual which is completely silent on the 240v motor/120v light question.
Do your machines have a 4-wire cord and NEMA 14 plugs to a 4-wire 120/240 circuit?
Tom Veatch Wichita, KS USA
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Tom Veatch wrote: ...

No, of course not!!! :)
They're the same as you describe simply using ground as neutral (for the outstanding load of a 60(75 max) W bulb I can't get particularly up in a tizzy :) ).
Of course, they're both a minimum of 30-40 years old; perhaps a new one might not do the same.
AFAIK NEC doesn't apply even yet for the reason you also cited; it's temporary load, not fixed which NEC doesn't address. What current UL is I don't know (nor really care :) ) and whether OSHA has their rules for commercial shops that would cover it I fortunately also don't have to consider.
As for your specific instance, what inspector and under what provision would you think he could red tag it given it is wired per the manufacturer's directions?
Primarily just commenting that at least at one time it was the quite common thing to do just as it was for dual-voltage appliances. Does Delta, for example, give any connection/wiring data for any current machines that indicate they supply 240V 4-wire cordsets or do they not supply the actual plug any longer? (I'd go look and see what I might find except the P-C site is abysmally slow w/ my dialup connection).
/EDITORIALIZING_EVEN_FURTHER_WARNING Were there really any widespread problems w/ that configuration? Personally have had both the range and the dryer for "since forever"; certainly since the late 50s/very early 60s and both are still of that configuration here. That's 50 years or so and in that whole time I've never, ever heard of an actual problem from it. Seems like another case of curing a disease that never was simply for the purpose of the Standards group continuing to need something to present as a result of their labors and to justify keeping meeting in Vegas/New Orleans/etc., ... :) [or :(, I'm not sure which, perhaps...] END_EDITORIALIZING_EVEN_FURTHER_WARNING/
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Tom Veatch wrote: ...

I intended to add in other response but since didn't I'll make this specific...
I'd think you should be able to find them pretty easily in Wichita. They're appliance lamps for ranges and also for the application specifically from any of the industrial supply houses I'd think.
The following link has at several from 40W to 100W; there are many others available if you really did/do want to go that route. As for me, I'd just leave it as is... :)
<http://www.buylighting.com/High-and-Low-Voltage-Specialty-Light-Bulbs-s/77.htm
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Every 240v bulb I've found locally in the proper wattage (40? or maybe 60, I disremember at this point) is a larger diameter (+1/4" ?) and has a different configuration model number (A21?) than the equivalent 120v "standard" A19 bulb. That's just enough larger to prevent it from fitting inside the cavity in the DP body.
Thanks for the link. I see they do have 40/60 watt 220v bulbs in the A19 size, but, since I've already gone to the trouble of reconnecting the chassis wiring to get 120v to the bulb and as you mentioned, I'm simply going to leave it the way it is, using the EGC as the neutral. It would take some extraordinary conditions for that arrangement to develop enough voltage to ground on the DP chassis to be a hazard. A large 120v load and a high resistance in the EGC path to ground could present a hazard, but a 40/60 watt load, even with a 2 ohm resistance in the ground path, would still only produce about one volt to ground on the chassis. A dead short to a high resistance ground could produce a fairly high voltage spike on the chassis but that would be the case regardless of the way the DP is wired and would only last until the breaker tripped..
Yeah, I know, it doesn't make a lot of sense to run a 3/4 horse motor on 240v, but as a matter of course, everything I have that has a dual voltage motor is configured to use 240. The reason is because when I first put in my shop, I was amperage limited by the size of the feeder the builder stubbed out for the shop when I had the house built in 1986. So, every stationary tool I bought, including the DP, was bought with a dual voltage motor and configured for 240 to keep the amperage draw as low as possible. That was all changed when I built a new shop building after I retire in 2002 and had a 200 amp service installed. (Yeah, it's overkill +) But, even with plenty of amperage available, I see no need to reconfigure the tools for 120v.
My feeling that hardwiring the machine in it's present configuration would be red-flagged is because I can't prove that's the manufacturer's recommendation. But, then I wouldn't go out of my way to bring it to an inspector's attention, assuming I wanted to hardwire the DP and did the permit/inspection rigamarole. The paper copy of my owner's manual doesn't show the "ground as neutral" configuration. I saw that in an online manual on the manufacturer's website while doing some research. Going back later to download a copy, I found that configuration has disappeared from the online manual. It now matches my paper copy and shows only connections for a 240v lamp. I suspect, but don't know for sure, the reason for the change is UL listing criteria. (BTW, the DP is a Jet JDP-17MF)
In any case, as you verified, we're still looking at 3-wire power cords with 2 conductors + ground even on 240volt tools. I suspect that 4-wire power cords on 240v plug-in tools - even those with 120v work lights - are rare to non-existant.
Tom Veatch Wichita, KS USA
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Tom Veatch wrote: ...

Unless this is a commercial shop (and even there I'd think it unlikely) I can't imagine that simply placing the connection to the DP in a junction box in an existing facility would require permits even in Wichita. Surely even inside the city limits the level isn't that great is it?
I'm outside 3-mi city-jurisdiction limits in SW County so there is no permitting/inspection required, thank goodness. I don't see how a farm producer would survive under that level of microscopic detail altho it's getting difficult w/ the increasing level of monitoring/reporting required for water/waste/fertilizer/pest-/herbicides/etc./etc./etc./... :(
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Most likely it wouldn't, but then, I'll never know because I'll never ask the question. Within reason, I go according to the old adages "If you think you won't like the answer, don't ask the question" and "It's better to ask forgiveness than beg permission". But, technically, you're modifying the permanent wiring of the facility and, if it's a slow day in the inspector's office, that could bring code compliance into question.
When I had the new shop built, the electrician just stubbed out individual 240v 3 wire (2+G) circuits to disconnects for my air compressor, cabinet saw, and cyclone. IIRC, he asked whether the loads required 120/240 or just 240. Those circuits terminated at the disconnects when the final inspection was passed. I wired the machines into the disconnects myself, without bureaucratic hindrance.... er.. assistance..., after the final inspection, so the code enforcement officers really have no true knowledge of how I configured those connections.
(Yes, my TS is hard wired.)
I was thinking more in terms of the general case than the specific instance of the DP. If a special purpose single phase circuit is run for a machine that requires 120/240v, (driers and ranges come to mind as the more common cases) current codes would require a 4-wire circuit.
Tom Veatch Wichita, KS USA
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Tom Veatch wrote:

If it's your house and you don't care about selling it then do whatever you want to.
If you plan on selling it then you want wiring to code and properly permitted--if someone asks the inspector to look at it he can make you rip out all unpermitted wiring and redo it before you can sell if he's wanting to be a pain in the ass about it.
If it's a commercial building you want to do it strictly by the book. Doing otherwise is asking for trouble.
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"Tom Veatch" wrote:

SFWIW
All the years I was in the electrical industry, major industrial customers had a spec limiting single phase motors to 1/2 HP.
Reason:
3 PH power was standard, 1 PH power had to be derived by installing a transformer which helped to create phase unbalance.
It was less expensive to standardize on 3 PH equipment.
As far as a 240V lamp, it's a standard offering but probably not stocked by distributors, but you are shooting yourself in the foot. (Can tell a story about George Steinbrenner and 240V lamps)
For incandescent lamps, the higher the voltage, the finer the filament.
The finer the filament, the more likely it will fail due to vibration.
For years, the majority of motor control indicating lights were transformer type, 120V primary, 6V secondary, /w/ 6V lamp filaments, just to overcome the vibration problems found with normal machine tools.
Lew .
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