Hello guys,

I want to renew my old house's fuse panel. I am conserned because when I opened the cover I found out that there are two old school handle-type "power disconnectors" - I don't know how they're called in english I'm not from english-speaking country so... Those things were used in old houses, especially russian-soviet built... So the thing is that one disconnector is on the phase and the other is on neutral, why is that? Also there are 2 automated fuses (screw in type) rated 10A each, which one of them connects all phase wires and the other connects all neutral wires. I'm not an electrician, but I know that you cannot put fuses in neutral, but maybe there could be some kind of reason for that? I made a simple scheme how I want to transform everything to a breaker panel, where the phase from main panel is protected by 16A circuit breaker and then for all 3 circuits I have there will be a 10A breaker places on phase and I'm going to connect all neutrals with wago and some alu-plus paste because I have aluminum wire comming from main panel from house. What are your thoughts? I may post some pictures later this week, because I don't have an access to the house right now. Thanks.

 

I have never been to Russia, but from what I have searched they use Schuko outlets. This outlet is not polarized and countries using non-polarized outlets tends to not care which wire is neutral and just treat both of them as live. In fact, depending the region, both wire may actually be hot.
Therefore, it is safer to disconnect both hot and neutral.

You can. It is just you have to have one on hot side and you don't have to have one on neutral side.

As for how the breaker should be wired, you should check with your local electrician as requirements will be different over there.

 

How can both wire be hot, wouldnt there be no potential difference between the wires and so no eletricity? Or it is possible that one wire has a shifted phase from the other? I checked with voltage tester and one wire gives signal while other does not, so it means that I have neutral, right?

P.S yes we have schuko outlets so you can connect appliances any way, but we still have to connect things like lights or switches the right way where hot it is hot where neutral we connect neutral and dont mix it.

 

Yes they can be supplied out of phase.

Countries that uses hot on both wires often use 2 pole switch to cut power to both wires instead of just hot side.

If you tested with non-contact tester, the side that does not beep is most likely to be neutral. However, non-contact testers can have false reading. If there is ground wire, test voltage between neutral and ground with a multimter. It should read 0.

One of reason they may use fuse on neutral is if panel mount fused disconnect switch is used. With panel mount, there is no enclose to hide wire splices. It is just more neat to have both hot and neutral going into a single disconnect switch then having neutral wires spliced together using other means.

 

How many wires come into the house ?
Two hot wires and a neutral or just a single hot wire and neutral.

I have never seen a neutral fused or disconnected and don't see the need for it. I'm just wondering if there are 2) 230v hot legs and one neutral coming into a house. As far as I knew.... there was only a single hot leg and a single neutral. Couldn't find much to collaborate online.

No power company would randomly connect a hot and neutral from their service to a residence.

 

Here are few examples.





They were just done to keep things neat back then. Especially when there are only small number of circuits. Not a common practice with breakers since they come in a single switch. But fused switches used to come as double pole only.

 

Hello again,

Sorry for the delay, so I went to check things this weekend and I upload a photo of the panel. It is really some bad stuff, two wires are isolated only with some tape. So I tested everything with a multimeter and here are the results: hot(right wire) to neutral(left wire) is 247V, neutral to ground(metal rod) is 0,1V, hot to ground is 210V, taped wire to neutral is 55V, other taped wire to neutral is 55V, taped wire to taped wire is 5V, taped wire to hot is 188V. So I can stick to my original plan, as there appears to be neutral and hot, but what could the other two cutted wires be? Why are they 55V to neutral? The cutted wire at the top I think is ground wire from shed, because there is no ground at the panel... Ugh so bad

 

Are you measuring voltages with a digital multi-meter?
If so, your readings below 100V are probably a induced voltage (aka phantom voltage) from wires running parallel to it. Test with some loads such as a light bulb.
Chances are they are no longer in use and disconnected inside as well.
Do not use that unknown wire as ground unless you can confirm that it is a ground. It looks very old panel and there may not have a ground wire to begin with.
If you can, follow the wire and check where it leads and see if runs to a grounding rod. Otherwise, you are better off installing grounding rods and run a new ground.

 

Yeah, I've tested it with digital multimeter. I haven't even thought about that, it is propably phantom voltage as you say but I'll make sure when I start work. One more question: is it okay that I will connect aluminum wires to circuit breakers and other DIN mounted things(I want outlet on my DIN)? I heard they tend to get loose, so I'll propably have to go and check situation every year or few? Or maybe I should connect aluminum to copper with some method and then connect copper wires to breakers? What would be best choise?

 

I forgot to mention why you get induced voltage with digital multimeter. Volt meter mode of digital multimeter has very high internal resistance, meaning puts near zero load on the circuit and it is close to a ideal voltmeter. Analog multimeter has lower internal resistance and puts some load on the circuit.

Do not use aluminum wire unless it is a thick service feed cable. They are pron to corrosion and caused many electrical fire in the US.
Aluminum wire on a properly rated breaker should not come loose if it is properly torqued and protected form corrosion. The problem is, outlets and switches on the other side also needs to be rated for aluminum wire. Also, aluminum and copper wires should never come in direct contact due to galvanic corrosion. You need a special connector to splice to copper wire.
Exposed aluminum wire can corrode easily and it is recommended to apply anti-corrosion compound (ie. Noalox and Ox-Gard). On a old aluminum wire, you should sand it to remove surface oxidation. Aluminum oxide is insulator and does not conduct electricity. This leads to high resistance and overheating.