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Anyone have a Mep 802A fU1 FUSE or konow of an equivalent fuse (F03A125V30A) ?

Suprman

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Looks like a standard fuse holder. You can probably pull it off and get a generic part number off the housing and find one online for a few bucks.
 

NormB

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Looks like a standard fuse holder. You can probably pull it off and get a generic part number off the housing and find one online for a few bucks.
Take that picture to radio shack and see if they have a standard 1.25" AGC fuse holder. They should. Unless they've sent back stock in preparation for closing. Sometimes you can find these at local auto stores, too.

Look for something like this, just use the cap.

IMG_0016.JPG
 

Guyfang

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FUSEHOLDER, EXTRACTOR, Part number FHN26G1, nsn: 5920-00-892-9311.

The part number will cross reference over to about 4-6 NSNs, but the one listed above will do fine. Put the NSN into your browser, and call it up. That will tell you where you can find a fuse holder/extractor just like the one in the gen set.

Or, you can go down to an electronics store and get anything that will fit the hole. Do not get a slow blow fuse. Get a fast blow fuse. The fuse is a 30 amp fuse.

Look closely in the control panel. The fuse and cap often wind up some place inside the control cabinet, where you would least expect it.

NormB, you beat me to it!
 

lindsey97

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There is a complete fuse holder nos in the classifieds.

Would you guys mind discussing why not to get a slow blow fuse, and what the differences are in the ceramic fuses. Never sold or stocked any ceramics in our family owned parts store.
 

Guyfang

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OK, there are several different types of fuses. Here in germany is what I know best, and I assume its the same in the states. Here we have a flink, normal and träger fuse. Translated to fast blow, normal and slow blow.

If you want to use a fuse to protect something vital, or easily damaged, you use a fast blow. If you are using a fuse to protect something that can pull a lot of amps for a very short time, but then the load drops down, like a starter,or motor, you use a slow blow. It hold just a tad longer, before popping. And if its not a big deal, normal.

And now, after looking at what I just wrote, it dawns on me that FU-1 is NOT a fast blow. Excuse me, I misspoke!! FU-1 is a normal 30 amp fuse. For some reason I confused it with FU-2. And FU-2 is a fast blow. It pays to have an extra FU-1 around. If you start blowing FU-2, you have a problem with your volt regulator.

The difference between ceramics and glass fuses? I would guess ceramic holds up better to heat, than glass. When you have a fuse in a circuit that draws a lot of amps, and continuously, ceramic will withstand the heat better.

The glass fuse is easier to see if its blown, but it can also be misleading. Sometimes it looks good, but is separated in the end of the tube, where you cant see it.

But Triple Jim could better answer I think.
 
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csheath

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Measure the depth and diameter. If it's a standard 1/4" X 1-1/4" you can get or order a 6F457 from Grainger.
 

Dwnorton1

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Slo-blow/time delay fuses are designed to be able to handle inrush of over their rated amperage for a certain period of time, ie. fuse to motor. Fast blow are normally used to protect devices that do not have high inrush current, ie electrical equipment. This is simple explanation as I understand it.

HRC sand filled ceramic are designed to prevent "high arc current" situation from developing by turning silica into glass, which is an insulator that suppresses any arc-over and breaks the circuit instantaneously vs. glass fuse that can sometimes fail to break during a heavy fault current which can lead to equipment failure and death if you were to replace an HRC fuse with glass fuse in your fluke and get across wrong source. Ending in a bad day. Never replace a HRC fuse with a glass fuse.
 

rcamacho

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Sorry for the old thread activation. I also need a replacement FU1 fuse.
Found a few on an auction site....



Sent from my iPhone using Tapatalk
 
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diyernh

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Yep. F03A125V30A is the same as BUS ABC-30-R. Mouser has a WAY better price than the one I posted above : https://www.mouser.com/productdetail/bussmann-eaton/bk-abc-30-r?qs=St27ATL478s0HesTffljHg==
My Fermont MEP-802A has a 32V BUSS AGC-30 in the FU1 fuse holder. From what I can see, this is the battery charging protection fuse(24VDC). Wouldn't the 32V, 30AMP be the correct one? The F03A125V30A is rated at 125VAC. That seems to be a high voltage fuse that wouldn't protect 24VDC circuits. ie 124/24 or 5 times too big?

What am I missing?
 

kloppk

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For fuses the voltage rating needs to be equal or higher than the voltage being protected. A higher voltage rated fuse will work just as well as one rated closer to the voltage being protected.
Generally a fuse rated for 120 VAC came be used to protect a DC circuit up to 60 volts. One half the AC voltage rating.
It all has to do with how the fuse is constructed so it blows properly to open the circuit during an overload.

So any 30 amp fuse rated at 32 volts or more DC or 60 volts AC or more would be suitable to use for FU1.
 

diyernh

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For fuses the voltage rating needs to be equal or higher than the voltage being protected. A higher voltage rated fuse will work just as well as one rated closer to the voltage being protected.
Generally a fuse rated for 120 VAC came be used to protect a DC circuit up to 60 volts. One half the AC voltage rating.
It all has to do with how the fuse is constructed so it blows properly to open the circuit during an overload.

So any 30 amp fuse rated at 32 volts or more DC or 60 volts AC or more would be suitable to use for FU1.
Thanks. The 32VDC AGC-30's were in a multi-pack in Home Depot. I'll stick with them. I have a friend that's off grid living that the MEP-802A just stopped, no power to crank, gauges, lights, etc. Just packing up possible necessary parts for the 5 hour drive next week.
 

diyernh

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It could be that diode CR1 failed. If it fails you loose all 24 volt power and you cannot dead crank the set.
CR1 is a 1N5405 3 amp diode.

In a pinch you can put a jumper across the terminals that CR1 is soldered to to restore power.
Thank you very much for the reply. I'm just learning these generators. I bought 2, one for my friend in NY and one for me. I do have some solar diodes at camp. Would these work in a pinch?


Or how long or what damage could occur if I left CR1 shorted for the winter? (long run times per day)

I still can pull my CR1 and bring it to NY if required, replacing mine when it arrives.


Are there any other components that I should order while I'm placing an online order? Spare components are cheap when you don't need them and worth gold when you do need them.

Sorry for the off topic conversation, but thanks for the help

Thanks,
DIyernh
 
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