Fuse Question

[JasonTX]

I am in the process of getting prepared to do the electrical on my camper and have decided to put an inverter in. Not being an expert in the field of electicity I decided to read the directions (I know, that's breaking the "man laws") for the inverter. Any how it says to put in a 100 ANL inline fuse. What the heck does the ANL mean? The lower model inverters listed in the manual require 50 A (amp), but my model has the ANL. Another question, where can I find the fuse and holder as all the local automotive and electronic stores do not carry such a thing. My goal is to follow the K.I.S.S method if that helps.

[madjack]

here is a link to show an ANL fuse and fuse block...I entered ANL fuse in google and came up with tons of sources......
http://www.vteworld.com/content/electro ... nlfuse.php

madjack

[asianflava]

ANL fuses are also called wafer fuses. They are for really high current applications upwards of 200A. We used them quite frequently when I used to install car stereos. I've actually seen them at Wal-Mart in the car stereo section.

When I wired up my inverter, I used an AGU fuse, looks like a regular glass fuse only giant sized. They don't handle as high a current as the ANL fuses up to around 100A. I like them because they are cheaper and the fuse holder is totally enclosed which would prevent accidental shorts. You can get a waterproof fuse holder for the ANL but it cost twice as much than the AGU holder.

I bought mine at www.partsexpress.com

ANL fuse

AGU fuse

[GeorgeTelford]

Hi Asian

There are more important design differences in fuses, many things need considering besides cost, blow speed, all 100 Amp fuses do not blow at same speed, also encapsulated are used were spark could be a problem.

What I am trying to say is that if an ANL is specified and AGU may give you an unexpected problem.

[bdosborn]

The AGU and ANL fuses are have essentialy the same time-current characteristics. They are both fast acting, single element fuses with no time delay.

Here's the ANL fuse curve

and here's the AGU fuse curve.

While the 100A AGU isn't listed in the literature, you can interpolate the characteristics from the fuse curves shown. You shouldn't have any problems substituting one for the other.
Bruce

[GeorgeTelford]

Hi Bruce

I have read the links that you provided and they are different on timings, I interpolated the characteristics (there is more good news see PS at the end)

The AGU fuse curve is flat down to one second and the ANL is curved all the way down from 10 Seconds

A AGU fuse needs 900 Amps to blow instantly and the ANL 1200 Amps ( and they both have different versions of instant )

Another important point is that the AGU is fast acting look at its top speed .01 ! the ANL is a slow blow by comparison.

The reccomended ANL fuse is a slower blowing, capable of sustaining Higher instantaneous surges.

PS the reason we had to interpolate the results for the AGU fuse is, luckily they do not make an AGU fuse of 100 Amps rating (I searched over and over and could not find any over 80 Amps), so the correct ANL fuse beckons.

Fuses are not as easy as they at first seem (because all fuses are not the same even if all the fuses are rated at 100 Amps the characteristics are different and can be critically important), if a certain type is specified it is best to use that type, unless you really do know the design criterium and the effect your change may have.

[bdosborn]

PS the reason we had to interpolate the results for the AGU fuse is, luckily they do not make an AGU fuse of 100 Amps rating

In that case, its a no brainer; go with the ANL.

You're correct, the AGU is a faster fuse but since they are typically acceptable with smaller inverters the differences between the AGU and ANL aren't significant enough in my mind to lean towards one or the other. (Unless they don't make one in the recommended size as you pointed out)
Bruce

[asianflava]

Hi Asian

There are more important design differences in fuses, many things need considering besides cost, blow speed, all 100 Amp fuses do not blow at same speed, also encapsulated are used were spark could be a problem.

What I am trying to say is that if an ANL is specified and AGU may give you an unexpected problem.

I am more familiar with AGU fuses, that's what we used before ANL and Maxi fuses became more available. Actually I have yet to use the inverter while camping. I wasn't satisified with the performance so I may have to redo it when I get a bigger inverter. Maybe new fuses will be in the plans for the remodel. For now, it is going to stay the way it is AGU fuse and all.

BTW: just google "100a agu" and some will show up. Wether or not they truly are 100A is a different story.

[GeorgeTelford]

Hi Asian

I do not like uncertainty so I have just checked to find a 100 AGU, they do not exist

I have just checked out 5 Catalogues, no sign of any AGU fuse above 80 Amps.

I also googled and although the results page implied there were 100 AGU fuses there is not one link to an 100 AGU ( the pages have 100 Amps and various AGU fuses on them, but not one 100 AMP AGU fuse )

Hi Bruce

I do get what you are saying and in this case to be honest if they were available either would probably do. The reason I jump on my box is that in some cases it could prove to be a critical difference.

Some devices with high surge ratings require a slower burn fuse (otherwise in high surge high temp conditions you could get nuisance fuse popping) so sometimes a lot of thought goes into exact fuse selection on other occassions simply max rating is used and any type (pretty much will do