A tiny metal sliver on the inside of my index finger

[amdx]

could have saved my life.

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until
I decided there's a problem. The tingle was at a tiny red spot on my
finger, I later removed a small metalic sliver. If not for the sliver I
probably would not have noticed the missing ground, for I don't know how
long.
The drill motor is a 3 wire system, hot, neutral and ground. I had it
plugged into a GFCI. I unplugged the drill and pushed the test button.
The GFCI didn't pop. I retrieved my DVM and tested from the drill case
the the dirt outside the door, it was about 80v. I then tested from the
Hot to the ground at the receptacle, that was about 20 v. I moved to
another Receptacle closer to the house, same thing no ground connection.
I moved up to a receptacle on the outside of the house on the same line,
again no ground connection. Inside the garage, no ground connection. I
opened the circuit breaker box and checked the ground wire, it is good.
So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.
Followup tomorrow evening.
Mikek

 

In sci.electronics.repair amdx <nojunk@knology.net> wrote:
> could have saved my life.

Good catch.

I unplugged the drill and pushed the test button. The GFCI didn't
pop.

The "test" button on the GFCI should work even if there is no ground to
the GFCI. So you may have more than one problem here.

Inside the garage, no ground connection. I opened the circuit breaker
box and checked the ground wire, it is good. So, in my attic between
the CB box and the garage there must be a connection box where the
ground has opened up.

Don't discount the idea that the ground is open at one of the
receptacles. In three houses I've worked on (one from 1965, two from
1969), if two or more NM cables come into a receptacle box, the ground
wires are just twisted around each other for an inch or two, with no
wire nut. Usually the contact between wires is OK but sometimes the
twist is not very strong. One of the ground wires is longer than the
others, and it goes to the green screw on the receptacle. When I swap
a receptacle in a box like this, I usually add a green wire nut with a
hole in the top for the long ground wire (Ideal "Greenie" or equal), to
help make sure the ground stays connected.

Besides, checking the receptacles is probably easier than fooling around
in the attic.

A good tool for quickly checking grounds is a 100 W incandescent lamp
in a socket that has insulated wire leads. Connect the wires live to
neutral to calibrate your eyes, then go from live to ground. If the
brightness drops off a lot, the ground has high resistance. (If there
is a GFCI in the circuit, going from live to ground should also pop the
GFCI.)

Matt Roberds

 

[Phil Allison]

"amdx"

could have saved my life.

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until I
decided there's a problem. The tingle was at a tiny red spot on my finger,
I later removed a small metalic sliver. If not for the sliver I probably
would not have noticed the missing ground, for I don't know how long.
The drill motor is a 3 wire system, hot, neutral and ground. I had it
plugged into a GFCI. I unplugged the drill and pushed the test button.
The GFCI didn't pop. I retrieved my DVM and tested from the drill case the
the dirt outside the door, it was about 80v. I then tested from the Hot to
the ground at the receptacle, that was about 20 v. I moved to another
Receptacle closer to the house, same thing no ground connection. I moved
up to a receptacle on the outside of the house on the same line, again no
ground connection. Inside the garage, no ground connection. I opened the
circuit breaker box and checked the ground wire, it is good.
So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.
Followup tomorrow evening.

** FYI:

GFCIs work independently of the safety ground in a 3 wire system - so will
still trip if a few mA of current is passing to any local ground like soil,
wet concrete or metal plumbing.

However, a missing safety earth conductor is never good as the metal cases
of 3 wire appliances can become live and nothing blows.

BTW:

I have not seen a 3 wire, hand held drill in quite a while.


.... Phil

 

[Jeff Liebermann]

On Fri, 02 May 2014 20:30:04 -0500, amdx <nojunk@knology.net> wrote:

So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.

<http://www.amazon.com/Electrical-Receptacle-Outlet-Ground-Tester/dp/B0012DHVQ0>
Buy one (or two) and walk it around to every outlet in the house. Also
check power strips which I've seen miswired.

> Followup tomorrow evening.

The life you save may be your own.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Trevor Wilson]

On 3/05/2014 12:01 PM, Phil Allison wrote:

"amdx"
could have saved my life.

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until I
decided there's a problem. The tingle was at a tiny red spot on my finger,
I later removed a small metalic sliver. If not for the sliver I probably
would not have noticed the missing ground, for I don't know how long.
The drill motor is a 3 wire system, hot, neutral and ground. I had it
plugged into a GFCI. I unplugged the drill and pushed the test button.
The GFCI didn't pop. I retrieved my DVM and tested from the drill case the
the dirt outside the door, it was about 80v. I then tested from the Hot to
the ground at the receptacle, that was about 20 v. I moved to another
Receptacle closer to the house, same thing no ground connection. I moved
up to a receptacle on the outside of the house on the same line, again no
ground connection. Inside the garage, no ground connection. I opened the
circuit breaker box and checked the ground wire, it is good.
So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.
Followup tomorrow evening.

** FYI:

GFCIs work independently of the safety ground in a 3 wire system - so will
still trip if a few mA of current is passing to any local ground like soil,
wet concrete or metal plumbing.

However, a missing safety earth conductor is never good as the metal cases
of 3 wire appliances can become live and nothing blows.

BTW:

I have not seen a 3 wire, hand held drill in quite a while.

**You got that right. My old man gave me my first electric drill (an
Hitachi, which I still use) back in 1967. It was a double insulated
type. He gave me my second electric drill (a variable speed Bosch in
1974 - which simply refuses to stop working). Also double insulated. He
kept using his aluminium cased Black & Decker for some reason. I have
not seen an earthed portable electric drill since at least that time,
though the old man's B&D is still in the family garage. It hasn't been
used in more than 20 years. Nor should it be. Terrifying things. Moreso
for those of us in 220-240VAC countries.


--
Trevor Wilson www.rageaudio.com.au

 

[Michael Black]

On Sat, 3 May 2014, Trevor Wilson wrote:

On 3/05/2014 12:01 PM, Phil Allison wrote:
"amdx"
could have saved my life.

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until I
decided there's a problem. The tingle was at a tiny red spot on my finger,
I later removed a small metalic sliver. If not for the sliver I probably
would not have noticed the missing ground, for I don't know how long.
The drill motor is a 3 wire system, hot, neutral and ground. I had it
plugged into a GFCI. I unplugged the drill and pushed the test button.
The GFCI didn't pop. I retrieved my DVM and tested from the drill case the
the dirt outside the door, it was about 80v. I then tested from the Hot to
the ground at the receptacle, that was about 20 v. I moved to another
Receptacle closer to the house, same thing no ground connection. I moved
up to a receptacle on the outside of the house on the same line, again no
ground connection. Inside the garage, no ground connection. I opened the
circuit breaker box and checked the ground wire, it is good.
So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.
Followup tomorrow evening.

** FYI:

GFCIs work independently of the safety ground in a 3 wire system - so will
still trip if a few mA of current is passing to any local ground like soil,
wet concrete or metal plumbing.

However, a missing safety earth conductor is never good as the metal cases
of 3 wire appliances can become live and nothing blows.

BTW:

I have not seen a 3 wire, hand held drill in quite a while.

**You got that right. My old man gave me my first electric drill (an Hitachi,
which I still use) back in 1967. It was a double insulated type. He gave me
my second electric drill (a variable speed Bosch in 1974 - which simply
refuses to stop working). Also double insulated. He kept using his aluminium
cased Black & Decker for some reason. I have not seen an earthed portable
electric drill since at least that time, though the old man's B&D is still in
the family garage. It hasn't been used in more than 20 years. Nor should it
be. Terrifying things. Moreso for those of us in 220-240VAC countries.

That's odd. My Black & Decker from 1975 (variable speed, but only one
direction) has a three prong plug, still works fine, though about 25 years
ago I had to put in replacement brushes.

In about the past five years, I bought another B&D drill at a garage sale
for a few dollars, that one maybe has two prongs, but the B&D drill that I
found in the garbage when the students moved out (which does reverse) is
three pronged.

Even that fancy detail sander I found last year, only to realize when I
got it home that it was a 220V unit, that has three prongs, of the
non-North American kind.

Of course, now one has the option of getting a cordless drill, which is
certainly a whole lot safer, and beats getting out an extension cord or
two to bring power to that distant location that requires a drill. I
don't use mine that much, but the first time I had to drill a hole and
didn't have to lay out the extension cord paid for that cheap cordless
drill.

Michael

 

[Phil Allison]

"Michael Black"

Phil Allison wrote:

I have not seen a 3 wire, hand held drill in quite a while.


That's odd. My Black & Decker from 1975 (variable speed, but only one
direction) has a three prong plug, still works fine, though about 25 years
ago I had to put in replacement brushes.

** A double insulated or "class 2" appliance may have a 3
pronged plug.

Egs, my Black & Decker 1600W heat gun and Atlas Copco
drill have 3 pin plugs but are clearly labelled "class 2" .

The AC cords have only two conductors.

In about the past five years, I bought another B&D drill at a garage sale
for a few dollars, that one maybe has two prongs, but the B&D drill that I
found in the garbage when the students moved out (which does reverse) is
three pronged.

** See above - look for the double square symbol.

Of course, now one has the option of getting a cordless drill, which is
certainly a whole lot safer,

** Well yes and no...

If you need to drill into walls it is possible to penetrate an AC
power cable and have the drill become electrified. Typically
the drill bit, chuck and metal cased gear box will be live -
the Atlas Copco drill has a plastic coating all over the chuck
and the drill body for this reason as do most modern units.



..... Phil

 

[John G]

Phil Allison wrote on 3/05/2014 :

"Michael Black"

Phil Allison wrote:

I have not seen a 3 wire, hand held drill in quite a while.


That's odd. My Black & Decker from 1975 (variable speed, but only one
direction) has a three prong plug, still works fine, though about 25 years
ago I had to put in replacement brushes.


** A double insulated or "class 2" appliance may have a 3
pronged plug.

Egs, my Black & Decker 1600W heat gun and Atlas Copco
drill have 3 pin plugs but are clearly labelled "class 2" .

The AC cords have only two conductors.

For a time in Aus there were sockets with shutters opened by the ground
pin.
I think they are still standard in the UK.

In about the past five years, I bought another B&D drill at a garage sale
for a few dollars, that one maybe has two prongs, but the B&D drill that I
found in the garbage when the students moved out (which does reverse) is
three pronged.

** See above - look for the double square symbol.


Of course, now one has the option of getting a cordless drill, which is
certainly a whole lot safer,

** Well yes and no...

If you need to drill into walls it is possible to penetrate an AC
power cable and have the drill become electrified. Typically
the drill bit, chuck and metal cased gear box will be live -
the Atlas Copco drill has a plastic coating all over the chuck
and the drill body for this reason as do most modern units.



.... Phil

--
John G

 

[Trevor Wilson]

On 3/05/2014 3:33 PM, Phil Allison wrote:

"Michael Black"

Phil Allison wrote:

I have not seen a 3 wire, hand held drill in quite a while.


That's odd. My Black & Decker from 1975 (variable speed, but only one
direction) has a three prong plug, still works fine, though about 25 years
ago I had to put in replacement brushes.


** A double insulated or "class 2" appliance may have a 3
pronged plug.

**Correct. Both my Hitachi and the Bosch use 3 pin plugs. The earth wire
is not used.

Egs, my Black & Decker 1600W heat gun and Atlas Copco
drill have 3 pin plugs but are clearly labelled "class 2" .

The AC cords have only two conductors.



In about the past five years, I bought another B&D drill at a garage sale
for a few dollars, that one maybe has two prongs, but the B&D drill that I
found in the garbage when the students moved out (which does reverse) is
three pronged.

** See above - look for the double square symbol.


Of course, now one has the option of getting a cordless drill, which is
certainly a whole lot safer,

** Well yes and no...

If you need to drill into walls it is possible to penetrate an AC
power cable and have the drill become electrified. Typically
the drill bit, chuck and metal cased gear box will be live -
the Atlas Copco drill has a plastic coating all over the chuck
and the drill body for this reason as do most modern units.

**I got a story about that too. A few years back I decided to replace
the incandescent fitting in part of my workshop with a double 37 Watt
fluoro fitting. As luck would have it, the wiring was installed in the
ceiling at the same time the slab was poured. I drilled a mounting hole
into the concrete ceiling............ You guessed it. Straight into the
conduit and into the wiring. Had to use surface mount conduit and
re-wire the whole bloody lot. GRRRR.

Yeah, I know. Shoulda used one of those wiring detector thingys.


--
Trevor Wilson www.rageaudio.com.au

 

[Mike Tomlinson]

En el artículo <N8adnXNibuRQCfnOnZ2dnUVZ_gGdnZ2d@westnet.com.au>, John G
<greentest@ozemail.com.au> escribió:

For a time in Aus there were sockets with shutters opened by the ground
pin.
I think they are still standard in the UK.

They are. It's a legal requirement.

--
(\_/)
(='.'=)
(")_(")

 

[amdx]

On 5/2/2014 8:58 PM, mroberds@att.net wrote:

In sci.electronics.repair amdx <nojunk@knology.net> wrote:
could have saved my life.

Good catch.

I unplugged the drill and pushed the test button. The GFCI didn't
pop.

The "test" button on the GFCI should work even if there is no ground to
the GFCI. So you may have more than one problem here.

Inside the garage, no ground connection. I opened the circuit breaker
box and checked the ground wire, it is good. So, in my attic between
the CB box and the garage there must be a connection box where the
ground has opened up.

Don't discount the idea that the ground is open at one of the
receptacles. In three houses I've worked on (one from 1965, two from
1969), if two or more NM cables come into a receptacle box, the ground
wires are just twisted around each other for an inch or two, with no
wire nut. Usually the contact between wires is OK but sometimes the
twist is not very strong. One of the ground wires is longer than the
others, and it goes to the green screw on the receptacle. When I swap
a receptacle in a box like this, I usually add a green wire nut with a
hole in the top for the long ground wire (Ideal "Greenie" or equal), to
help make sure the ground stays connected.

Besides, checking the receptacles is probably easier than fooling around
in the attic.

A good tool for quickly checking grounds is a 100 W incandescent lamp
in a socket that has insulated wire leads. Connect the wires live to
neutral to calibrate your eyes, then go from live to ground. If the
brightness drops off a lot, the ground has high resistance. (If there
is a GFCI in the circuit, going from live to ground should also pop the
GFCI.)

Matt Roberds

Re: checking in receptacle boxes, I thing I have it somewhat isolated.
The CB box and the garage are on opposite ends of the house, and as far
as I know, the garage is on a breaker by it's self. But it also looks
like there is a connection box between the CB box and the garage, or at
least a break in the ground wire. It seems a little odd, I'll figure it
out this afternoon.
Mikek

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

 

[amdx]

On 5/2/2014 9:01 PM, Phil Allison wrote:

"amdx"
could have saved my life.

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until I
decided there's a problem. The tingle was at a tiny red spot on my finger,
I later removed a small metalic sliver. If not for the sliver I probably
would not have noticed the missing ground, for I don't know how long.
The drill motor is a 3 wire system, hot, neutral and ground. I had it
plugged into a GFCI. I unplugged the drill and pushed the test button.
The GFCI didn't pop. I retrieved my DVM and tested from the drill case the
the dirt outside the door, it was about 80v. I then tested from the Hot to
the ground at the receptacle, that was about 20 v. I moved to another
Receptacle closer to the house, same thing no ground connection. I moved
up to a receptacle on the outside of the house on the same line, again no
ground connection. Inside the garage, no ground connection. I opened the
circuit breaker box and checked the ground wire, it is good.
So, in my attic between the CB box and the garage there must be a
connection box where the ground has opened up.
Followup tomorrow evening.

** FYI
GFCIs work independently of the safety ground in a 3 wire system - so will
still trip if a few mA of current is passing to any local ground like soil,
wet concrete or metal plumbing.

Yes, good reminder, I knew it was a difference between the hot and
neutral, but when I was missing ground my mind went elsewhere.

However, a missing safety earth conductor is never good as the metal cases
of 3 wire appliances can become live and nothing blows.

BTW:

I have not seen a 3 wire, hand held drill in quite a while.


... Phil

It is old, scares me now!
Mikek



---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

 

[amdx]

On 5/3/2014 3:26 AM, Trevor Wilson wrote:

On 3/05/2014 3:33 PM, Phil Allison wrote:
"Michael Black"

**I got a story about that too. A few years back I decided to replace
the incandescent fitting in part of my workshop with a double 37 Watt
fluoro fitting. As luck would have it, the wiring was installed in the
ceiling at the same time the slab was poured. I drilled a mounting hole
into the concrete ceiling............ You guessed it. Straight into the
conduit and into the wiring. Had to use surface mount conduit and
re-wire the whole bloody lot. GRRRR.

Yeah, I know. Shoulda used one of those wiring detector thingys.

I have told this before, stop me if you've heard it
I put several freezers in our screened porch, and plugged them into
the existing outlets. It was a few years later when I smelled something
in out dining room. We sniffed it out but never come up with a source.
Several days later we smelled something again, is seemed like it was in
a corner where we had a TV. A 32" CRT on wheeled cart over carpet, in a
tight spot. I moved it far enough to get my hand on the plug, it was
hot. Nothing was wrong with the plug, it was the outlet.
Moved everything out of the corner and removed the paneling. I found
the outlet had a loose connection that got hot when the freezers ran.
It was a pass through connection to the screened porch. The box had
seriously degraded, it was crumbly plastic and the wiring was clearly
overheated. I did a proper repair and replaced the outlet.
I made a plan and added a sub panel with 4 circuit breakers and 7 new
outlets in the screened porch.
Mikek


---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

 

[Adrian Tuddenham]

amdx <nojunk@knology.net> wrote:

I was in my workshed which is about 60 ft from the house drilling some
aluminum. I got a faint tingle in my hand, I touched the case of my
drill a couple times and didn't feel any thing, so I started to drill
again. I noticed the tingle again, I went through this a few times until
I decided there's a problem. The tingle was at a tiny red spot on my
finger, I later removed a small metalic sliver. If not for the sliver I
probably would not have noticed the missing ground, for I don't know how
long.

Depending on the grounding arrangements, this can sometimes still happen
even if there isn't a complete disconnection or any serious leakage
current.

The sensation of electrical shock is entirely dependent on the current
density in the susceptible tissues, rather than the voltage applied.
Human tissues are very conductive, but dry skin usually acts as a
partial insulator so low voltages don't create enough current to cause
any sensation.

With a sliver of metal puncturing the skin and leading directly into the
underlying tissue, probably quite close to nerve endings, a very low
voltage would develop enough current to be easily detectable. Tests
have suggested that A.C. voltages below the 2v level can be detected by
the tongue when the feet are in a wet, conductive environment.

This is a particular problem where the neutral and earth conductors are
bonded ("P.M.E." in the UK) because the small voltage dropped along the
neutral will apear on any bonded "earthed" metalwork. In farms and
other wet environments, this can lead to animals receiving shocks from
licking handrails, feeding troughs - and from milking machines through
the milk lines directly to their teats.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

 

[John Robertson]

On 05/03/2014 6:36 AM, amdx wrote:

On 5/3/2014 3:26 AM, Trevor Wilson wrote:
On 3/05/2014 3:33 PM, Phil Allison wrote:
"Michael Black"

**I got a story about that too. A few years back I decided to replace
the incandescent fitting in part of my workshop with a double 37 Watt
fluoro fitting. As luck would have it, the wiring was installed in the
ceiling at the same time the slab was poured. I drilled a mounting hole
into the concrete ceiling............ You guessed it. Straight into the
conduit and into the wiring. Had to use surface mount conduit and
re-wire the whole bloody lot. GRRRR.

Yeah, I know. Shoulda used one of those wiring detector thingys.


I have told this before, stop me if you've heard it
I put several freezers in our screened porch, and plugged them into
the existing outlets. It was a few years later when I smelled something
in out dining room. We sniffed it out but never come up with a source.
Several days later we smelled something again, is seemed like it was in
a corner where we had a TV. A 32" CRT on wheeled cart over carpet, in a
tight spot. I moved it far enough to get my hand on the plug, it was
hot. Nothing was wrong with the plug, it was the outlet.
Moved everything out of the corner and removed the paneling. I found the
outlet had a loose connection that got hot when the freezers ran.
It was a pass through connection to the screened porch. The box had
seriously degraded, it was crumbly plastic and the wiring was clearly
overheated. I did a proper repair and replaced the outlet.
I made a plan and added a sub panel with 4 circuit breakers and 7 new
outlets in the screened porch.
Mikek

Freezers should have their own breakers - one per freezer. Food safety
is part of it - you don't want the freezer losing power because someone
trips a breaker and doesn't do anything about it...

But mainly the freezers simply draw too much current to have them share
the power line with anything else. Like air conditioners. Check your
state/provincial/etc. wiring codes...

John :-#)#
--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

 

[amdx]

On 5/3/2014 6:37 PM, John Robertson wrote:

On 05/03/2014 6:36 AM, amdx wrote:
On 5/3/2014 3:26 AM, Trevor Wilson wrote:
On 3/05/2014 3:33 PM, Phil Allison wrote:
"Michael Black"

**I got a story about that too. A few years back I decided to replace
the incandescent fitting in part of my workshop with a double 37 Watt
fluoro fitting. As luck would have it, the wiring was installed in the
ceiling at the same time the slab was poured. I drilled a mounting hole
into the concrete ceiling............ You guessed it. Straight into the
conduit and into the wiring. Had to use surface mount conduit and
re-wire the whole bloody lot. GRRRR.

Yeah, I know. Shoulda used one of those wiring detector thingys.


I have told this before, stop me if you've heard it
I put several freezers in our screened porch, and plugged them into
the existing outlets. It was a few years later when I smelled something
in out dining room. We sniffed it out but never come up with a source.
Several days later we smelled something again, is seemed like it was in
a corner where we had a TV. A 32" CRT on wheeled cart over carpet, in a
tight spot. I moved it far enough to get my hand on the plug, it was
hot. Nothing was wrong with the plug, it was the outlet.
Moved everything out of the corner and removed the paneling. I found the
outlet had a loose connection that got hot when the freezers ran.
It was a pass through connection to the screened porch. The box had
seriously degraded, it was crumbly plastic and the wiring was clearly
overheated. I did a proper repair and replaced the outlet.
I made a plan and added a sub panel with 4 circuit breakers and 7 new
outlets in the screened porch.
Mikek


Freezers should have their own breakers - one per freezer. Food safety
is part of it - you don't want the freezer losing power because someone
trips a breaker and doesn't do anything about it...

But mainly the freezers simply draw too much current to have them share
the power line with anything else. Like air conditioners. Check your
state/provincial/etc. wiring codes...

John :-#)#

mmm... My sub panel has four-20 amp circuit breakers with 7 outlets.
Plugged into these are 12 freezers plus an ice maker, 400lb per day. The
sub panel was installed back in 2008 or 2009. In those 5 or 6 years I
have never popped one circuit breaker. I thought it possible that two
freezers would try to start at the same time and I might pop one, but it
has never happened. I don't have all 12 freezers on all year, but there
are months when all 12 are in use.
I also have a One Wire System to monitor the freezer temperatures, with
a red alert if the temp gets up to 5* F. First thing every morning when
I wake up the computer I check the freezer temperatures.
Mikek

 

[Leif Neland]

amdx skrev:

mmm... My sub panel has four-20 amp circuit breakers with 7 outlets.
Plugged into these are 12 freezers plus an ice maker, 400lb per day.

Have you considered getting a refrigerated container instead of the 12
freezers?

Leif

--
Husk křrelys bagpĺ, hvis din bilfabrikant har taget den idiotiske
beslutning at undlade det.

 

I was going to say because you do not need all the capacity all the time. The emptier the freezer the more it costs to run. I know it doesn't make sense on its face, but it works that way for some reason. I don't know if it has to do wit the opening of the door and thermal mass or what, but even if not, if you only used on efreezer instead of a bunch, it would be like opening all of them up at the same time.

The reliability factor can be dealt with actually by having spare parts and/or a redundant system. This would probably only pay to do if the value of what is in there warrants it.

Another comment, just for the hell of it - I have noticed on Craigslist for example, that people ares elling off these digitally run appliances. In fact on eposter in one of the sci.electronics groups was worried about using a generator or invertor or whatever on a digitally controlled refrigerator. A motor and a mechanical thermostat wouldn't care.

I think microprocessors should usually be kept out of certiaon appliances. I would like this old microwave I had a long time ago. Mechanical timer, but two power levels. This baby had an extra tap on the transformer for low power.

At my house, which I am uinfortunately selling, one of the furnaces is an old thrmopile system. It works without electricity at all. So do the hot water tanks, but I see a few now that use electricity. (I mean gas ones) Refrigerators should not be digital. In fact, wasjing machines and dryers should not be digital.

It is just asking for trouble. Now IF they could control the internal combustion engine well enough without electronics I think that would be good. In fact, the ECM does NOT tume the engine perfectly because there has to be something to burn in the catalytic.

Technology is wonderful, but the fact is that it is not always better. think of the mechanical thermostat in a fridge or freezer. An electronic circuit is actually chepaer. the chips that run tuners in TV and recievers are chaper than the old tuning caps or turret, or even wafer tuners. The voltage to control the volume on sometning coming from a microprocessor is cheaper than a potentiometer.

It is not like technology is bad, I could never say that. I say it should be avoided in certain applications, like the steering and brakes on a car. The fact is though, that electronics is the cheapest way to do it.

Enough rant... Next.

 

[amdx]

On 5/4/2014 5:21 PM, Leif Neland wrote:

amdx skrev:


mmm... My sub panel has four-20 amp circuit breakers with 7
outlets. Plugged into these are 12 freezers plus an ice maker, 400lb
per day.

Have you considered getting a refrigerated container instead of the 12
freezers?

Leif

At one time we had one, but they blow cold dry air over our product
which causes freezer burn in a short time. The chest freezers have
worked well for 10+ years and when a freezer stops working I don't have
to worry about moving 6000lbs to a new freezer I don't have.
I just move 650lbs to the empty freezer we always have, because
we always keep one freezer empty, for emergencies.
Mikek

 

[amdx]

On 5/6/2014 3:27 PM, mroberds@att.net wrote:

amdx <nojunk@knology.net> wrote:
It would be easier if the conduit was one size larger, I think it
is 3/4" now.

Unfortunately that conduit stretcher I ordered a few years ago is still
on back order. It's stuck in the same place as the door stretcher (for
getting large equipment into a building).

I have large (maybe 500watt) sodium vapor? light that quits when I
start my sander or skil saw.

These come in several sizes; the ones in the big box stores seem to
be 70 W or 150 W but bigger ones exist.

Ya, this is in a housing that is more than a foot wide x 10".

In a few more years, humans will be able to afford an LED replacement
with equal light output, but probably not yet. (Protip: You have to
buy it just as soon as it's barely affordable, while there is still
some QC on the ballasts. Once it gets really cheap, the ballast will
have been outhoused to People's Shining LED Ballast Factory #39, and
the assembly will start lasting 1/10 of the lifetime of the LED chips.)

It takes a minute to get started again.

It's normal for that kind of lamp to take a little while to restart,
but the fact that it goes out means you have some pretty good voltage
drop right now.

That's why I mentioned it.

Anything wrong with 2-10s and 1-12 for the grd?

Is the shed fed with a 15 amp breaker, 20 amp breaker, or something
else? Normally the ground is the same size as the live and neutral, but
since at least the live and neutral are bigger than they need to be, I
think it is OK. I am not an electrician though.

I think you said this is plastic conduit? Looking at the conduit fill
tables I can find online, 3/4" schedule 40 is good for fifteen 12 AWG
wires or nine 10 AWG wires. Schedule 80 (thicker wall) is 12 and 7
respectively. Plastic conduit will have "Sch 40" or "Sch 80" printed
on the side. If it's some other kind of conduit, Google for "conduit
fill table" and have fun.

Is stranded wire ok by code? I think it is.

I think it is too; it's a lot easier to pull into conduit than solid.
Over a certain size (about 10 or 8 AWG) all you can get is stranded.

One difficulty I have had with stranded wire is trying to attach it to
a switch or receptacle. No matter how hard I twist the strands, it
wants to unravel a little when I bend it into a loop and put it under
the terminal screw. If you have the style of terminal where you put
the wire straight in under a plate, and then tighten the screw down on
the plate, stranded works fine. (This is different than the push-in or
back-wire terminals, which only "work" with solid wire.)

If the first place inside the shed that the wire from the conduit goes
is a disconnect/breaker box, or it gets wire-nutted to the wiring inside
the shed, you won't have this problem. If the first place the wire from
the conduit goes is a switch or receptacle, you might have a better time
if you splice on 6" or so of solid wire with a wire nut, and connect the
solid wire to the device.

Matt Roberds

I've been working on the project since 9am. I now have about 16ft of
new conduit in and ran all new wire, no connections underground. I
replaced what was 12 gauge with 10 gauge. I had a bit of a snag getting
the cable puller ran through the conduit. I started at the other and and
had the same problem. A little end adjustment and it made it through the
snag. Once I got things going it pulled very easy, if
not for that connection problem you mentioned, I may have ran a couple
more #10s and really looked after that voltage drop. I had thoughts
about doing that but decided the connection would be a fight.
At this point, I have not reburied anything or made any connections
at either end. I'll probably just pick up tools before dark and finish
on another day.
My memory failed me, I did not bury a box, I put in two of the small
elbows with access covers held by two screws. These made a U around the
tower that started the whole problem.
I'll post a couple of pictures after I rest.
Mikek