J.P.
Senior Member
- Location
- United States
Ul listed fuse substitutes.
- Thread starter J.P.
- Start date
- Status
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Thanks for the chuckle. I needed it today
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
The device in the bottom-middle is going to be a puzzlement for the younger set...
junkhound
Senior Member
- Location
- Renton, WA
- Occupation
- EE, power electronics specialty
I'ma waitin' to hear from folks with some 'real life' fusing current measurements on an 11 mm wrench.
Only have direct experience with 7/16" wrenches <G>
Them there 11 mm wrenches don't quite fit mosta my USA type bolts, don't quite fit over the head - maybe that why they get used for fuses ?
Only have direct experience with 7/16" wrenches <G>
Them there 11 mm wrenches don't quite fit mosta my USA type bolts, don't quite fit over the head - maybe that why they get used for fuses ?
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
7/16 wrench fits NEMA standard devices, the 11MM fits IEC standard devices, they are not interchangeable:happyyes:
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
It's because at 50Hz, the melting point of a 7/16 wrench might be higher than that of an 11mm wrench.
Stick to the original design parameters people...
fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
Where is the coinage that says "in God We Trust". I always thought that was the "ur-fuse substitute".
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
many don't trust God anymore, and the coins have less copper then they used to as well so their fuse rating has changed
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Prior to 1982, pennies were 95% copper, 5% zinc (tin was removed in 1962). In 1982 they switched to 97.5% zinc, 2.5% copper, essentially copper plated zinc.many don't trust God anymore, and the coins have less copper then they used to as well so their fuse rating has changed
Zinc is only 27% of the conductivity of copper, so that means higher resistance, which means at the same amount of current through it, more watts lost and higher heat, but melts at a temperature 70% lower than copper. That means you can't put even a small fraction of the amount of current through a new penny fuse as our fathers could with an old penny fuse. That probably explains why it is no longer on the chart...
Work is a tad slow today and I'm at home nursing a sprained knee...
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fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
Well, that's progress -- new pennies are safer!
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
But when you go over 60 amps the ends of fuses typically are blade type instead of round, and I don't think any of those are long enough to fit 60 amp 600 volt fuseholders either:ashamed1:I believe that customers should always get a audible & visual indication anytime a fuse blows:
This set will cover any application, from residential to industrial.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
You had to go rain on my parade.
I was just starting to work on a discussion of the advantages of belt-fed versus magazine-fed fuses.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
You had to go rain on my parade.
Well if you have a feed mechanism - you have automatic reset, kind of like a substitute for a recloser
HoosierSparky
Senior Plans Examiner, MEP
- Location
- Scottsdale AZ
- Occupation
- Senior Plans Examiner
When I worked in a steel mill, we used a 2/0 crimp lug as a replacement for 30amp 250v fuses on crane control boards. We called it "doing the smoke test". We would just follow the smoking wire to the bad contactor, then pull the switch.
- Status