220V Extension Cord - Recommendations?

[Coen]

[member=7493]Sparktrician[/member]
Without having completely read the 3 page PDF; it looks like that applies to fixed installations, not extension cords.

It also doesn't differentiate between a lot of different methods of installation.

For example. If we take the list of 18 to 8 AWG 3-wire loaded 90 degree cable, it lists these currents;
18
25
30
40
55

Compare that to what we have here for 3-wire 90 degree (C) cables, directly buried;
23
30
39
49
65

The current ratings from that document are very close (slightly above) for what we have for 'wire in conduit in thermal insulation'. Nowhere near applicable for having an exposed extension cord.

And still; those tables are for 3-wire loads, not simple 2-wire loads which would be the case in the question from [member=75204]jordanrossbell[/member] . The current rating would again increase ~17%

Eaton's 20A isolator switch doesn't even allow for 4mm^2 (12 gauge) wiring to be connected btw.

“Are American amps different?‘

No, but voltage is different.

1300 watts divided by 220 volts = ~ 6 amps, so a lightweight power cord is fine.

1300 watts divided by 110 volts = ~ 12 amps, so a heavier cord is needed.

Yes I know. I was taking on the list of [member=7493]Sparktrician[/member]

“We use 1.5mm^2 (=16 gauge) extension cords for everything up to and including 16A”

Wow [blink] 16 amps of 220volts is 3500 watts. Do you even have anything that pulls that much? A heater? Does the cord get hot when carrying that much current?

Cooktops, ovens, dish washers, boilers; lots of stuff that draws 16A perfectly fine over 1.5mm^2. The cord can get warm, but so what. Better than having this huge anaconda as an extension cord. Unless you have an insanely high % of utilization you are not gonna earn back the extra investment either. For solar panel installations it's different; you base it own return on investment. 4mm^2 cable often makes financial sense even if 1.5mm^2 would still be within limits.

Festool CTL's come with an 1.5mm^2 cord and have a 2400W rated outlet on them, per official Festool specs.

[member=8955]Coen[/member], the table referenced is "Ampacities of Insulated Conductors with Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried)".  Due to the limited ventilation (heat dissipation) of enclosed cable, the table gives a margin for safety.  An inspector told me many years ago to go with the ampacities specified, just in case someone inadvertently causes the ventilation for portable cable to be compromised, and that this advice applied to cable inside wall plenums.  I've heeded that advice and have never had to do any rework per inspectors' instructions.  I'd much rather be safe than smoking...

So what this really is is that you "simplified" the rules beyond what they actually say, resulting in claiming a heavier, thicker, more expensive cord is required while it's not.

 

[Sparktrician]

[member=7493]Sparktrician[/member]
Without having completely read the 3 page PDF; it looks like that applies to fixed installations, not extension cords.

It also doesn't differentiate between a lot of different methods of installation.

For example. If we take the list of 18 to 8 AWG 3-wire loaded 90 degree cable, it lists these currents;
18
25
30
40
55

Compare that to what we have here for 3-wire 90 degree (C) cables, directly buried;
23
30
39
49
65

The current ratings from that document are very close (slightly above) for what we have for 'wire in conduit in thermal insulation'. Nowhere near applicable for having an exposed extension cord.

And still; those tables are for 3-wire loads, not simple 2-wire loads which would be the case in the question from [member=75204]jordanrossbell[/member] . The current rating would again increase ~17%

Eaton's 20A isolator switch doesn't even allow for 4mm^2 (12 gauge) wiring to be connected btw.

“Are American amps different?‘

No, but voltage is different.

1300 watts divided by 220 volts = ~ 6 amps, so a lightweight power cord is fine.

1300 watts divided by 110 volts = ~ 12 amps, so a heavier cord is needed.

Yes I know. I was taking on the list of [member=7493]Sparktrician[/member]

“We use 1.5mm^2 (=16 gauge) extension cords for everything up to and including 16A”

Wow [blink] 16 amps of 220volts is 3500 watts. Do you even have anything that pulls that much? A heater? Does the cord get hot when carrying that much current?

Cooktops, ovens, dish washers, boilers; lots of stuff that draws 16A perfectly fine over 1.5mm^2. The cord can get warm, but so what. Better than having this huge anaconda as an extension cord. Unless you have an insanely high % of utilization you are not gonna earn back the extra investment either. For solar panel installations it's different; you base it own return on investment. 4mm^2 cable often makes financial sense even if 1.5mm^2 would still be within limits.

Festool CTL's come with an 1.5mm^2 cord and have a 2400W rated outlet on them, per official Festool specs.

[member=8955]Coen[/member], the table referenced is "Ampacities of Insulated Conductors with Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried)".  Due to the limited ventilation (heat dissipation) of enclosed cable, the table gives a margin for safety.  An inspector told me many years ago to go with the ampacities specified, just in case someone inadvertently causes the ventilation for portable cable to be compromised, and that this advice applied to cable inside wall plenums.  I've heeded that advice and have never had to do any rework per inspectors' instructions.  I'd much rather be safe than smoking...

So what this really is is that you "simplified" the rules beyond what they actually say, resulting in claiming a heavier, thicker, more expensive cord is required while it's not.

[member=8955]Coen[/member], I have found it a good idea to go along with the inspector's recommendation rather than argue every point.  I get paid for getting work completed.  I do NOT get paid for arguing over niggling points with the inspector who has the authority and right to shut down a worksite.  Capisce?

 

[Coen]

[member=7493]Sparktrician[/member] And how does that apply to a private citizen using an extension cord in his garage? Do you have inspectors for that too in the land of the free?

 

[rst]

Coen, for the most part excepting residence and land use the consumer is as free to be as stupid as wants.  All my tools including 220v are mobile, 12 Powermatic 100 planer, drill press', Jet 16/32 sander, router table, table saws etc,  All are wired with 10ga SJ.  Working 45 years commercial/industrial site work has definitely influenced my decisions regarding electricity and capability.

 

[Coen]

There is nothing stupid about a 1.5mm2 extension cable for

 

[tsmi243]

There is nothing stupid about a 1.5mm2 extension cable for