Fuse Box Wiring HELP PLEASE!!

[shawnswan]

I am fairly confident in my wiring abilities, however I have never wired a panel before. I just installed a 30 amp fuse box into my boler. I brought my main hookup wire in ready to attach when I realized I didn't know where it goes. I searched the web endlessly but nothing. Can somebody here please help me?!?!?!?! I'm attaching a photo of the fusebox.
Thanks in advance!!

[Lance MacArthur]

Strange box, but probably workable. If there is no bus (copper slab between the two fuses, you will prebably have to split the incoming black (hot) wire, and connect to each side. It looks like the center bus on the bottom is a place to connect your neutral (white) wire. The ground (green) should be screwed into the box side somewhere, unless there is a clip to connect it (didn't see one).

It looks like your incoming wires are a little light for a 30 amp circuit. You should be using at least #10 wire for that, and larger if your cord is more than 10' or so.

Good luck! Don't get fried.

[shawnswan]

Thanks for the help!! I'll give that a try.
Regarding the wires you see in the photo, I drew them in using photoshop.

[Steve L.]

I agree that there should be a common bar for the hot. The base of the fuses should connect to the incoming hot wire. Barring a common bus, I agree the top appears to be for the incoming hot wire.

Before I hooked up anything, I'd check with an ohmmeter that the center connectors on the bottom aren't a ground by checking continuity between the connectors and a bare spot on the box. If there's no continuity, then I suppose the incoming white goes to the center of the three screws, and the outgoing whites (to the receptacles) would be either side of the center connector. The outgoing blacks to the receptacles would be the two outside, bottom screws.

The current comes from the source, into the box through the black, goes to the top of the box, through the fuse, out the outgoing black to the receptacle, through the appliance, back through the white to that common 3 screw center bit and back out the white and the box back to the source.

The incoming ground and the outgoing grounds would all be connected together and attached to the case as suggested.

Morgan knows about this stuff, I hope he checks in.

[Jim Hovind]

I think I would get a small 110 breaker box from a DIY store and do it right. Those kind of fuses are hard to find.

[Morgan]

I agree that there should be a common bar for the hot. The base of the fuses should connect to the incoming hot wire. Barring a common bus, I agree the top appears to be for the incoming hot wire.

Before I hooked up anything, I'd check with an ohmmeter that the center connectors on the bottom aren't a ground by checking continuity between the connectors and a bare spot on the box. If there's no continuity, then I suppose the incoming white goes to the center of the three screws, and the outgoing whites (to the receptacles) would be either side of the center connector. The outgoing blacks to the receptacles would be the two outside, bottom screws.

The current comes from the source, into the box through the black, goes to the top of the box, through the fuse, out the outgoing black to the receptacle, through the appliance, back through the white to that common 3 screw center bit and back out the white and the box back to the source.

The incoming ground and the outgoing grounds would all be connected together and attached to the case as suggested.

[b]Morgan knows about this stuff, I hope he checks in.

You're very kind, Steve, but you said it quite well.

I have to plead ignorance; I didn't know you could still buy these boxes with Edison based fuses. My guess is the box is intended for 240 volt operation with one fuse for each leg of the 240 volt feed.


I have to agree with Jim, I'd get a small 120 volt breaker box rated for 30 amps and with breaker positions for the main breaker (single pole 30 A) and a breaker position for each AC circuit (i.e., lighting, outlets, A/C, microwave).

[Joe MacDonald]

this is a typical fuse box generally used for water heaters.
the black lead would connect on the top on one side and need to be jumpered across to the other top terminal.

the bottom terminal below each fuse is the output.

the two centre terminals are definitely for the neutral(white wire)

I don't see a ground lug, one should be added so you have a common ground point for all 120v connections.

Don't just stick the ground wire under a mounting screw, that would violate the NEC(US), and the CEC(Canada)
I agree with everyone else, a breaker box would be better, but these fuses are still common, most electric ranges still use them.

[Roger H]

I confess that I am an electrical know-nothing. I did manage to install a 30 amp breaker box in my Burro last year with a new 30 amp pigtail though. I have an apartment building that was built in 1950 that still has fuse boxes, and fuses are still easy to find; unless you're in the back woods of some campground at 2am when your electric heater blows one for you. A breaker is, frankly, much easier to reset!

For that reason, I'd also recommend a breaker box. I think the total was around $30 including the box and two breakers for the one I installed with two 15 amp circuits; one for the A/C install, and one for the rest of the trailer's electrical. Fortunately the nice people who build them label the contacts now just for dummies like ME!

Roger

[D Shubel]

I'm no engineer, and you are probably going to purchase the breakers as everyone suggests...but curiosity has gotten the better of me.

If I came across that in my egg my first thought would be that one fuse is for shore power and the other is for 12 v from the battery. Someone please help my curiosity and understanding

[shawnswan]

Thanks for all your help, it makes sense to me now!!! See the attachment, this is what I have concluded from the posts above.

[Pete Dumbleton]

That looks good, but were I you, having the challenge, I would now go get a modern breaker box and install it.