220v protection

[Guy Dotan]

My shop now has a 4 220v outlets, each 2 are connected to a double 20amp breaker. My question is about electrocution protection: is there anything I should add? I am used to the european standard, which **I believe** has a main arc fault breaker.

[Mike Heidrick]

These are more unisaw than sawstop. Just DON'T do it.

[Mike Cutler]

Guy

If they are properly installed, per NEC (National Electrical Code), you should be fine. The machine(s) should be grounded to the electrical system.
AFCI's, Arc Fault Current Interrupters, in the US, are for protection against fires starting inside walls due to electrical arcing at the boxes, and is "normally" associated with,and applied to, the 120vac lighting and convenience duplex receptacles wiring in common living spaces, which is why there is also a code for "Arc Gap" clearance on drywall fitting around electrical boxes.
GFCI's, Ground Fault Current Interrupters, are also utilized.Their application, per code requirements, are different than AFCI's.

[Wade Lippman]

It is almost impossible to electrocute yourself on household current. If your wiring is proper and you are not standing in water, you are almost certainly good. (occasionally someone has a heart condition or just exceptionally bad luck, but the main danger is hurting yourself jerking away from the shock.)

Our AFCIs do have a GFCI effect, but the threshold is too high to prevent shocks; though I don't know about European AFCIs.

[Mike Chalmers]

These are more unisaw than sawstop. Just DON'T do it.


Wrong thread?

[Rollie Meyers]

My shop now has a 4 220v outlets, each 2 are connected to a double 20amp breaker. My question is about electrocution protection: is there anything I should add? I am used to the european standard, which **I believe** has a main arc fault breaker.


Arc Fault is snake oil, there is a proposal to require GFCI protection in the next edition of the NEC in shops and garages for 240V, The EU uses a RCD not arc fault, AFCI is pure American garbage. It has never done what was claimed and who knows if it ever will, the idea is good though.

[Guy Dotan]

Arc Fault is snake oil, there is a proposal to require GFCI protection in the next edition of the NEC in shops and garages for 240V, The EU uses a RCD not arc fault, AFCI is pure American garbage. It has never done what was claimed and who knows if it ever will, the idea is good though.

You are right. European is RCD and it looks like it is similar so GFCI. So the question becomes: should I put GFCI breakers for the 220v? How about the 110v

[Rollie Meyers]

110 and 220 are obsolete, it only still exists in the 50 Hertz world, the US uses 120 and 240V, if you have A/C drives (VFD's) on equipment GFCI's do not like them & will trip, but any 120 volt receptacle in a shop, garage, storage building requires GFCI protection, only way to get around it is to hard wire it, it is not required to have GFCI protection on 240V shop receptacles, the choice is up to the user.

[glenn bradley]

These are more unisaw than sawstop. Just DON'T do it.


Wrong thread?

I'm thinkin' :)

[Wade Lippman]

Afghanistan, Iran and a few African countries are 220v 50hz. Illinois was never 50hz, so the OP is not using an obsolete term, but rather a wrong term. There are lots of stories about why people say 110, but nothing solid.

I am not aware of any requirement for GFCI in hobby woodworking shops. Some, perhaps most, might, but not all.

[Brian Hood]

My shop now has a 4 220v outlets, each 2 are connected to a double 20amp breaker. My question is about electrocution protection: is there anything I should add? I am used to the european standard, which **I believe** has a main arc fault breaker.
Guy,
You refer to Europe and to electrocution protection. In Europe electricity is 230v to ground, which means if you get a shock it has an electrical pressure of 230 volts through your body. That may or may not be dangerous depending on how well you conduct any resulting current to ground; standing on a dry ladder you might not feel anything, standing in a sink of salt water with copper drain lines I'm not sure you would survive.
In the US it's mostly (much safer) 120v to ground, so you will find it very difficult to get a 240v to ground shock. More likely a 240v shock will be from one part of your hand/arm to another, because you have to get onto both hots (phases) at the same time. As someone who has received such it is seriously annoying but never required even a 3 minute break to recover from. If this still concerns you then some type of GFCI protection can be set up, and may be advisable if you have a clay studio or some other water intensive activity. Bottom line, you are in almost no danger.
Arc Fault protects you from house fires. GFCI protects you from being shocked. Anyway that's the theory.

The above is also true of 3-phase, except the voltage is then 120 and 208. The reason for that is obvious if you have a ruler and measure 3 point on a circle.

Hope this helps,
Brian(J)

[Rollie Meyers]

The EU 230V standard came about because some countries were 415/240V and others 380/220V they "harmonized" the voltages as 400/230V, nothing changes but everyone is under the same standard. 110/220 went away to become 115/230V, which went away long ago to become the now standard 120/240V for residential.

[Guy Dotan]

Guy,

In the US it's mostly (much safer) 120v to ground, so you will find it very difficult to get a 240v to ground shock. More likely a 240v shock will be from one part of your hand/arm to another, because you have to get onto both hots (phases) at the same time. As someone who has received such it is seriously annoying but never required even a 3 minute break to recover from. If this still concerns you then some type of GFCI protection can be set up, and may be advisable if you have a clay studio or some other water intensive activity. Bottom line, you are in almost no danger.
Arc Fault protects you from house fires. GFCI protects you from being shocked. Anyway that's the theory.

The above is also true of 3-phase, except the voltage is then 120 and 208. The reason for that is obvious if you have a ruler and measure 3 point on a circle.

Hope this helps,
Brian(J)


Thanks a lot. This makes sense!

[Bill Space]

Brian said: "In Europe electricity is 230v to ground, which means if you get a shock it has an electrical pressure of 230 volts through your body. That may or may not be dangerous..."

I think Brian meant to say that the resulting shock "may or may not be fatal." 230 volts applied to the human body is always dangerous. People have been both shocked and killed by 115 volts or less. Respect the dangers normal voltages present...be they 115 or 230...

Bill