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what does low voltage limiter mean in this context?

Cut and paste from the document, FOR your entertainment. :)

"This bulletin is intended to clearly present comprehensive product data and provide technical
information that will help the end user with design applications."
 

"Cable limiter​

A cable limiter is similar to a fuse but is intended only for protection of low voltage power cables. It is used, for example, in networks where multiple cables may be used in parallel. It is not intended to provide overload protection, but instead protects a cable that is exposed to a short circuit. The characteristics of the limiter are matched to the size of cable so that the limiter clears a fault before the cable insulation is damaged." -- https://en.wikipedia.org/wiki/Fuse_(electrical)#Other_circuit_protectors
 
Data sheet shows 35A fuse, carrying 100A clears in 5 seconds. Definitely non time delay.

Littlefuse describes a similar name, "Cable limiters are fusible devices that provide very fast shortcircuit protection, primarily to faulted cables, but also to other conductors such as busway. Cable limiters do not have an ampere rating, and cannot be used to provide overload protection. They are instead selected by cable size; for example, a 500 kcmil cable requires a 500 kcmil cable limiter."


(You beat me to posting it)

Here's one closer to what you posted:


Seems to be a fast fuse, rather than slow-blow
 
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Would you believe I was slow until 4th grade?
About that time I demo'd for the class what I presented as an "ESP machine" (it was really more of sensory deprivation.)
Classmate tried it and reported hearing his brother talking. Teacher didn't even encourage further investigation of it.
Public education wasn't anything special, but at least there were shop and science labs.
 
I get to take the Arc/flash class in a couple weeks. This will be at least my 3rd time. Apparently it expires every couple years (and each time was for a different employer.)
At (a certain federal research lab) although I was a "qualified electrical worker", I was forbidden to replace a fluorescent bulb. Guess what might first professional job was, as a 17 year old just out of high school?

Fuses - they're related to the arc blast topic. Worth having a cover over.
 
I will start by saying I don’t know for sure nor have I been able to come up with any documentation but, I think the word “ limiter “ is used because it won’t clear a short in the normal 4 ms. I only find “ limiter “ used with this class fuse ANL, CNL,ANN. If anyone has anything else I would love to hear it.
 
I was looking for terms like "current limiting"

A class T fuse is "current limiting", and if a fault (in an AC circuit) delivers as much as 200,000A short circuit current, the class T fuse blows so fast energy deposited in other series-connected components (switches, smaller breakers or fuses) is no more than they would normally experience when a 20,000A fault is cleared.

What this would do is allow a 22kA interrupt capability main breaker to hold together, not explode, while the class T fuse blew.
It isn't really limiting current, the 200,000A will flow, but time is limited because the class T fuse blows faster.

Similarly, a 22kA rated main breaker trips fast enough that 10kA rated branch circuit breakers don't become a safety hazard.

So that's what I thought "limiter" might mean. But I didn't find any such reference.
(My first thought was it was the British word for fuse. They use funny terms, you know.)

... because it won’t clear a short in the normal 4 ms.

Have any links to charts quoting clearing times that short?
The trip curves I've seen aren't shown below 10 milliseconds, which is a bit more than one phase of 60 Hz AC.
I haven't seen details on how the DC rated OCP devices perform with DC, in terms of clearing.
I've only observed that class T, rated 200kA for AC, is rated 20kA for DC. And while it is "current limiting" for that high AC current, down at 20kA it doesn't blow fast enough to protect anything downstream rated for less. Would be good to find a fuse that protects 2kA or 5kA devices.
 
Data sheet shows 35A fuse, carrying 100A clears in 5 seconds. Definitely non time delay.
I'm trying to wrap my head around why there's no time delay. The time-current chart is all about delays.

It appears to me the fuses are rated for wire fusing current in 20 ms.

If I got this right, the 35 fuse correlates to about 5 awg wire. The fusing current of 5 awg copper is 800 A.
The 100 fuse correlates to 0 awg. The fusing current is 1900A.

Those are the data points at 20 ms.
 
There is always some time delay in a thermal element, of course. Just seconds for overload to a low multiple of rating, in the case of these fuses.

Time to overheat a copper wire is far longer. It's ampacity rating is much lower current per unit cross-section, and temperature rise at rated current is much less. Fuse blows fast enough with these fast-blow the wire doesn't warm up much.

Typical time-delay thermal/magnetic breaker, wiring gets a bit too hot and insulation degrades. Good for about 100 cycles of overload, I've read. After that, your house wiring is toast.

12 awg house wiring really has 30A ampacity, but NEC requires 20A OCP. Similarly 10 awg 40A, 30A OCP. 14 awg 20A, 15A OCP.
That probably allows near unlimited overload cycles without damage. Good considering consumer has option to plug in loads, as compared to hardwired dedicated circuit for heavier loads.
 
My read? Not a time delay fuse. Is a low voltage fuse. Will limit amperes - fuse.
 
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