Dust Collection - the final answer

[dbfletcher]

Al, I am a little confused. If you are grounding your output tray to your dust vacuum, and your dust vacuum is grounded to the mains via a three pronged plug, what would be the difference to grounding the CW machine to the mains via a three pronged plug?

The think the point there was that LHR would have had a much more difficult time with the UL requirements if they used a grounded three prong plug. So I dont think there really is a differnece for your question above... but as end user, we are not required to get UL approval. At least that was my take on the posts.

Doug Fletcher

[Digitalwoodshop]

Yes, as IS the machine works just fine with no dust collection induced voltages and a 2 wire plug. When we add the air flow and the dust we generate static voltage. My way to dissipate the voltage it to ground the outfeed tray of the machine bleeding off any voltage. Had I not grounded the frame the static will eventually seek out the path of lease resistance to ground through the negative or ground side of the power supply... Like the car frame and a battery.... Isolated... Like when you have dry air and carpet in your house and you shuffle your feet and touch metal... SNAP.... That is why the Vacuum Cleaner Hoses KILL machines... It enters the power supply through the negative side of the components and ZAPS the Semiconductors....

The higher the quality of the vacuum hose the more conductive carbon in it to dissipate the voltage. The Cheapest of Vacuum hoses made from semi hard plastic are the best VOLTAGE Producers.... Holding on to grounded metal with one hand and the cheap vacuum hose with the other while you vacuum helps as does turning OFF the machine while you vacuum....

As for the Servo Motors... Don't have a clue on them yet.... I was going to take the Driver Transistors in the Computer and see what the parameters were on them someday....

Just remember that if you disassemble the servo motors that have magnets in them and put them back together it is very likely they will never work again. You must apply a "Magnetic Keeper" to the servo when you remove the Rotor or the Permanent magnets in Stator will demagnetize. They must then be placed in a jig to remagnetize the servo motor. I wrote about this about 2 months ago and posted some links.

AL

[JDPratt]

Just remember that if you disassemble the servo motors that have magnets in them and put them back together it is very likely they will never work again. You must apply a "Magnetic Keeper" to the servo when you remove the Rotor or the Permanent magnets in Stator will demagnetize. They must then be placed in a jig to remagnetize the servo motor. I wrote about this about 2 months ago and posted some links.

AL

Al, I don't think there is much chance of me trying this one. I am still trying to decypher your lost post. Man that stuff just went right over my head. I can build a house, plumb it, wire it, and trim it out and you made me feel a little stupid there. I'm glad guys like you are on this forum, because without you guys giving advice, I know I would be totally lost.

John

[wasacop75]

Let me see if i got this right....
If i drag my feet this time of year across carpeted floors and i touch my wife's ear she screams.....Good enough.....

Static with the machine...not good.

So, if we have dust collectors, you cant get enough grounding wires..

[Digitalwoodshop]

Let me see if i got this right....
If i drag my feet this time of year across carpeted floors and i touch my wife's ear she screams.....Good enough.....

Static with the machine...not good.

So, if we have dust collectors, you cant get enough grounding wires..

Correct you cannot get enough ground wires BUT... Never drive a Ground Rod in near your shop and ground you equipment... The Main Power panel in your house should be the main ground. If you use another grounding point a thing happens called "Ground Loops" Where the Ground near your shop might be more Positive in voltage than your meter entry power panel and "Strange Things happen with Electrical Equipment with Ground Loops..

Ground everything Through your dust collector...

http://en.wikipedia.org/wiki/Ground_loop_(electricity)

http://www.epanorama.net/documents/groundloop/

And one that will let you appreciate your CW... Ground Loops and a ShopBot... http://www.talkshopbot.com/forum/mes...tml?1251060934


AL

[JDPratt]

Okay, I am a slow learner with this. So you are saying that grounding the machine to the metal frame of the DC is adequate because the three prong electrical plug on the DC has its own ground?

[Frederick_P]

Okay, I am a slow learner with this. So you are saying that grounding the machine to the metal frame of the DC is adequate because the three prong electrical plug on the DC has its own ground?

Why not simply replace the two pronged cord on the CW machine with a three pronged cord as the ground would then be the same as that of the dust collector?

[DocWheeler]

JD,

That is correct, just tie your machine to the ground wiring of your electrical system. You can do that by going to the DC itself or any ground in any receptacle. Swapping the two-conductor for a three-conductor cord to the CW would do this also.

[dbfletcher]

JD,

That is correct, just tie your machine to the ground wiring of your electrical system. You can do that by going to the DC itself or any ground in any receptacle. Swapping the two-conductor for a three-conductor cord to the CW would do this also.

Would LHR be required to remove the three prong if it was sent in for repair? That would put it outside of the UL spec right?

Doug Fletcher

[castingman]

An idea

When i set up my ham radio station i ran a wire from the ground bus in the service panel to a copper bar mounted on a wood stand with 15 1/4" holes drilled in it . All of my ham gear is connected to the bar and no GROUND LOOP.

Just an idea.

Michael