Garage/Workshop Build

[ejb11235]

I'm going to wade into this discussion, even though 1) I haven't read every posting word for word, and 2) I am not an electrician.

The neutral wire is a current-carrying conductor. If you bond the neutral and grounds at the sub-panel, the current that normally would flow only in the neutral will now be carried in both the neutral and the grounding system.

From Wiring a House Rex Cauldwell, Taunton Press: "The neutral bus must not be connected to the panel frame--only the grounding bus can do that in a subpanel. This is to prevent neutral current from flowing through the grounding system on the load side of the main breaker (which is a code violation). Doing so would place current through the metal conduit and ductwork, creating a shock and fire hazard."

Even when a separate ground wire is run from the main panel to the sub panel, bonding neutral and ground at the sub-panel will still result in current flow through the grounding system.

Other resource: https://structuretech.com/subpanels-when-the-grounds-and-neutrals-should-be-separated/

 

[GreensvilleJay]

That's a nice ,easy to understand reply although, when you read the 'link'...

' In short, it’s not always an improper installation if the grounds and neutrals are connected together at a subpanel. It depends on when it was installed and what else is going on. '

Adds even more confusion ! Apparently it's OK, if pre2008. maybe ancient electrons flowed differently than the new ones ??

I'd have thought a 'recall' or 'upgrade to current code' law would have been issued.
In Ontario, when permits are pulled for a reno, EVERYTHING has to be 'put up to code'.In the case of electrical, that means nearly every cirsuit must have the $$$$ arc-fault breakers.

 

[lynnmor]

Perhaps adding a ground rod to the detached building might add some protection from lightning or other power surge.

 

[ejb11235]

That's a nice ,easy to understand reply although, when you read the 'link'...

'In short, it’s not always an improper installation if the grounds and neutrals are connected together at a subpanel. It depends on when it was installed and what else is going on.'

Adds even more confusion! Apparently it's OK, if pre2008. maybe ancient electrons flowed differently than the new ones ??

I'd have thought a 'recall' or 'upgrade to current code' law would have been issued.
In Ontario, when permits are pulled for a reno, EVERYTHING has to be 'put up to code'.In the case of electrical, that means nearly every cirsuit must have the $$$$ arc-fault breakers.

Yes, I also thought it was interesting to read that the code evolved over time on this issue. I just assumed that a neutral/ground bond in a sub-panel was an immediate code violation. But apparently not. That of course, doesn't make it safe.

I would venture to say that a lot of code exists to address and mitigate actual risks that are realized over time, not hypothetical risks. That, and creation of new products that can address them. Certainly, you can imagine the type of push-back a code-setting committee would get if they proposed a new rule based on a hypothetical risk. It's when people start to get hurt or die that real motivation for change arises.

 

[Freeheeler]

Electrical is done. I have 2x 20amps circuits for all outlets. 1 15amp for lights and 1 30amp for the heater (5000w)

Just a suggestion. I didn't see anything for a 220 line. I didn't add any when I built my mancave thinking I didn't need it. I later put in a 220v window a/c unit and had to run a new line and redo the box. Luckily my panel was oversized and had plenty of room to add to. I'm now putting in 2 more 220 breakers and another 110 breaker since a welder needs a 220 and the Bendpak lift needs it's own 110. Even though you may not need them now, consider any future possible needs.
The progress looks great, keep posting pics.

 

[RCW]

Just a suggestion. I didn't see anything for a 220 line.

Have to agree here.

When I put a sub panel in my garage I had no use for a 240v, but I put in 2. Welder and compressor were possibilities.

Few years later, been considering adding more of both 240 and 120.

 

[Dieseldonato]

it's a rather confusing issue really.
the 'don't bond' doesn't work with 240 volt equipment ( neutral is not used....)
I prefer the ground wire to be bigger than the rest, so it's conduct the 'bad' electrons away FASTER than a smaller wire would....
some of my panels USE Mother earth as the return, can get 15 miles of solid communications.

This depends on your area, any new 220/240 has to have a 4 wire conductor set, separate neutral and ground wires.
Half the confusion were having is the difference in locations.

 

[GreensvilleJay]

Guess they wire nut or snip off the neutral as it's NOT being used ??

 

[Dieseldonato]

Guess they wire nut or snip off the neutral as it's NOT being used ??

Neutral and ground really do about the same thing, return to source. Just down here locally ( Pennsylvania, USA) we have to have separate grounds and neutrals. So for example the 60 gal air compressor I recently got, has a 4 wire plug. The 2 hot legs go to the pressure switch, then to the motor, the neutral goes straight to the motor and the ground goes to a ground terminal on the frame of the motor. I assume it's redundant. Just in case there's stray voltage foe some reason it has an easy path to ground (source) I would assume it about the same reason for secondary ground rods, closer for it to go to earth at the shed then follow the wiring back to the main panel then to the main ground rod. Which in my main panel the neutral and ground have a tie strap in between them anyway.

 

[GreensvilleJay]

have to ask...
...the neutral goes straight to the motor ...

what does it connect to ??

220 motor doesn't normally need the neutral..
jes curious.
Jay

 

[Dieseldonato]

have to ask...
...the neutral goes straight to the motor ...

what does it connect to ??

220 motor doesn't normally need the neutral..
jes curious.
Jay

Think we're talking about different types of 220. Here in the states it's 2 110 volt legs and 1 neutral plus a ground wire. I klalways forget you guys run higher voltage on a single leg.

 

[GreensvilleJay]

Any '220' motor doesn't NEED the neutral. Think 5HP aircompressor motors ,only need L1 and l2 from the main panel ( red and black). Most well pumps are wired for 220v operation, again red and black,NO neutral.
All home electrical panels in Canada and USA are 220volt center tapped( blk is 120, red is 120, wht is the neutral or center tap of the transformer on the pole.

 

[ejb11235]

Any '220' motor doesn't NEED the neutral. Think 5HP aircompressor motors ,only need L1 and l2 from the main panel ( red and black). Most well pumps are wired for 220v operation, again red and black,NO neutral.
All home electrical panels in Canada and USA are 220volt center tapped( blk is 120, red is 120, wht is the neutral or center tap of the transformer on the pole.

Some motors are dual-voltage, so they can be wired in a 220volt or 110volt configuration. I would think that such motors would have a neutral connection that's used only when the motor is wired for 110volt operation.

 

[ejb11235]

Neutral and ground really do about the same thing, return to source....So for example the 60 gal air compressor I recently got, has a 4 wire plug. The 2 hot legs go to the pressure switch, then to the motor, the neutral goes straight to the motor and the ground goes to a ground terminal on the frame of the motor. I assume it's redundant.

I am not an electrician, but I think this the notion that neutral and ground are the same thing is fundamentally incorrect.

As I stated in my previous post, the neutral is a current-carrying conductor. The ground is not a current-carrying conductor, except in a fault condition. This distinction is important. If there's a break in the neutral (e.g. a wire nut in a j-box comes off and the wires separate), there will be voltage present on the neutral coming from the load. If a ground were to separate, there should be no voltage present. The ground won't be able to do its job, but there shouldn't be any voltage on it. The purpose of the ground is to provide a safe return path for voltage in the event that a hot wire shorts to it. This prevents, for example, the frame of the appliance from becoming hot, and also allows the circuit breaker to trip.

The neutral and ground are not redundant. They serve entirely different purposes and exhibit different characteristics (e.g. current and voltage) during normal operations. That the neutral and ground are bonded in the main panel (the "service equipment"), does not change this.

 

[awesome]

Electricity is done. Approved by an electrician. I'm a bit disappointed by the LED lighting. I mifht need to add 2 more sets (I have 3 for a total of 9000 lumens).

I'd like to get a few suggestions for concrete floor sealers. I'm in the ottawa region, so there the tractor will bring snow and dirt a lot on the floor if that matters.

I heard epoxy doeant breathe so if humidity build up under the slab, the epoxy can bubble up. Acrylic sealers go for about 400$ for a pail. I was hoping for way cheaper than that.

 

[awesome]

The neutral and ground are not redundant. They serve entirely different purposes and exhibit different characteristics (e.g. current and voltage) during normal operations. That the neutral and ground are bonded in the main panel (the "service equipment"), does not change this.

Agreed. There seems.to be a lot of confusion in this thread about ground. Ground and neutral are not the same. You never want power going to ground. This can be proven with a GFCI: gfci will trip if neutral and hot are unbalanced. This can happen if the hot is shorted to ground or through you.

The reason you can get electrocuted by touching a cable is because electricity wants to go to the ground. If there is a short in a box somehwere and you tpuch the box, power will flow to ground instead of your body because your body is much more resistive than the ground cable. Cut the ground and power will flow thru you instead. That is not the function of the neutral cable. Neutral can kill you just as well as the hot wire.

 

[58Ford]

Just a suggestion. I didn't see anything for a 220 line. I didn't add any when I built my mancave thinking I didn't need it. I later put in a 220v window a/c unit and had to run a new line and redo the box. Luckily my panel was oversized and had plenty of room to add to. I'm now putting in 2 more 220 breakers and another 110 breaker since a welder needs a 220 and the Bendpak lift needs it's own 110. Even though you may not need them now, consider any future possible needs.
The progress looks great, keep posting pics.

Agreed. Add a 220 line in. I am doing similar to you and also have a bendpak lift. The 220 version costs no more and operates faster so I got the 220 version.

 

[GreensvilleJay]

re: sealer...

do NOT put anything on for at least 2 months. usually concrete 'cures' in 30 days,but really longer is better
I never bothered 'sealing' my garage floor as I USE my garage and 'stuff' drips...oil,paint, antifreeze,chemicals,etc. It was purdy back in '81 all new, now it has CHARACTER !
Decided a long time ago if someone says 'you should seal the floor' !', I reply 'go ahead YOUR money and YOUR labour'. It's still not sealed.

re: lights...
I added quad receptacle boxes on the ceiling ,4 spots ( 2 car garage), plug in Princess Auto LED lights (when on sale).....The older I get, the more light I need.....

 

[awesome]

re: sealer...

do NOT put anything on for at least 2 months. usually concrete 'cures' in 30 days,but really longer is better
I never bothered 'sealing' my garage floor as I USE my garage and 'stuff' drips...oil,paint, antifreeze,chemicals,etc. It was purdy back in '81 all new, now it has CHARACTER !
Decided a long time ago if someone says 'you should seal the floor' !', I reply 'go ahead YOUR money and YOUR labour'. It's still not sealed.

I'm not too worried about stains. Like you said, it adds character. I just want it to be easy to sweep. The surface is a bit rough, it's not mirror-like so I thought adding a sealer or paint of some sort would help

 

[58Ford]

Our garage is 1250 sq ft. There was only two local options for a painted floor that have decent warranties. The floor cost was $6k. The shop is 2000 sq ft so it’s going to hurt for sure. Jay is 100% on the money, the longer you leave the new floor the better the adhesion will be. Absolute minimum is a month.

I’ve done the do it yourself versions and they just don’t hold up for vehicle traffic, just foot traffic yes. Decent warranty is 10 years.