24V + 10A = Fire?

[Mickey]

Is this a new word

Never heard of it before, just sounds funny to me

Google gives me 99,300 hits

http://www.google.com/search?q=ampa...s=org.mozilla:en-US:official&client=firefox-a

 

[Bruce99]

Is this a new word

Never heard of it before, just sounds funny to me

This does not surprise me from your answer. The word is in the Canadian Code Book index over seven times. One would have to read the book to know this.

 

[Gil47]

I'm wondering if it's possible for 24V to create enough heat to melt cords going to switches (22 AWG, Inductive Proximity Switches). I've never seen it happen and was just curious if maybe we had something or someone playing around where they shouldn't.

My first reaction to reading the above was that some one had been welding near this machine, and did not place there earth electrode properly, which allowed the welding current to pass thru the wires going to the SWITCHES, in order to get a return path, this would melt the wires very quickly.

I have seen this happen on many occasions.

 

[Tharon]

Just to offer some clarification.

The wire that melted was a 22 AWG 3 conductor pigtail off of a small switch.

What I assumed had happened was somehow the switch failed and shorted (or maybe just partially) and was drawing more current than it should have. Since the power supply was fused at 10A, the switch could draw plenty of current to burn up the wire before the fuse would blow.

I had just never ran into this situation before.


Edit:

And also, ampacity is a real word, not only is it used in the Canadian Code, but the NEC code book as well.

 

[mrtweaver]

I can tell you this much. At a facility I once worked for we had several machine that were purchased from a Germany MFG. And it was nothing to see 10amp and 15amp rated 24Vdc P.S. And like you I to had some meltdowns. So what I done, is where possible, took the 10 or 15 amp service wire and landed it on terminal strips then seperates the subfeeds and fused them accordingly. You see sometime they would take a 10 or 15 amp feed, which was on about size 14 wire, then they would tie in all the clutches, brakes, and switches, and these would be at a much smaller scale wire. SO I just seperated the circuits and refused where capable, this fixed the problem.

I'm just curious, cause I ran into an issue with melted cords today.

Most of the time when I'm using 24V for switches, there are so few things that need it, it's only a 50W power supply and it's fused at 2A.

This machine I had an issue with was fused at 10A (For all the 24V controls... and there are a lot). It seems as though the switches should have been grouped together and fused seperately lower (But I didn't make the machine, so it wasn't my call).

I'm wondering if it's possible for 24V to create enough heat to melt cords going to switches (22 AWG, Inductive Proximity Switches). I've never seen it happen and was just curious if maybe we had something or someone playing around where they shouldn't.

 

[PeterW]

This does not surprise me from your answer. The word is in the Canadian Code Book index over seven times. One would have to read the book to know this.

I'm still trying to get to grips with this AWG sizing of wires, we use 'mm' in Europe, find it confusing that the bigger the number the smaller the wire

Never know I may read the Canadian Code Book one day.


From what I've seen so far though, the panels here would noit be acceptable in the UK, that's for sure.

 

[Stationmaster]

Google gives me 99,300 hits

"Google" is this a new word

Never heard of it before, just sounds funny to me

Stationmaster

 

[Tharon]

So if you Google Google, does the internet get stuck in an infinite loop?

(sorry, off topic and all...)

 

[mordred]

you end up with a turkey on the screen

 

[Stationmaster]

So if you Google Google, does the internet get stuck in an infinite loop?

(sorry, off topic and all...)

I don't know....guess it depends on its Googlepacity