ᐅ How to Find a Cable Break Using a Multimeter?

We have purchased an old villa and are currently renovating it. We are now looking for cable breaks and found multimeters for electronic professions online. But how do you use something like that? Could you please help us? Thank you!!!

Hello Dirkbuerger,

If you have purchased an old villa and are now looking for cable breaks, I assume the electrical installation is outdated.

I would definitely get in touch with two or three electricians who can inspect your electrical system, give you advice, and explain how to use a multimeter.

You will probably also find an electrician who allows you to do a large part of the work yourself (for example, laying and pulling cables), while the electrician connects the wires.

Best regards

K.Brodbeck

It doesn’t work by simply connecting a multimeter to a wire and having it show you exactly where the break is. You need to know the specific resistance of the wire, and based on the measured resistance, you can estimate roughly where the break is located. If the installation is outdated and partially damaged, I strongly recommend renewing it. First, an outdated installation is dangerous because faulty wiring can cause fires. Old installations can also potentially increase electricity consumption. And if you hire an electrician to spend hours measuring the wiring, you will pay a lot of money and still end up with an old system. That’s why it’s better to replace everything at once, so you can have peace of mind for at least the next 30 years.

You will probably find an electrician who allows you to do a large part of the work yourself (e.g., laying and pulling cables) and then the electrician will connect the wires.

It’s nice of you to offer tips on saving money, but how is he supposed to know where to run what? Should I use a 3-core or 5-core cable to the switch? Does the outlet require a conductor cross-section of 1.5mm² or 2.5mm²? And what exactly is the difference between NYM-J and NYY cables?

Simply putting something conductive into the wall is not enough. That’s why I think a professional should handle it. It won’t help if the electrician comes to connect everything but can’t hook up half of it because the wrong cables were installed. That would only make it more expensive than just having a professional do it from the start.

KNX-Partner schrieb:
It's nice of you to give tips on saving money, but how is he supposed to know where to install what?
Do I need to run a 3-core or a 5-core cable to the switch? Does the outlet require a conductor size of 1.5mm² or 2.5mm²? And what exactly is the difference between NYM-J and NYY cables?

Simply running any type of current-carrying cable inside the wall isn’t enough, so I think a professional should be involved. It doesn’t help if the electrician comes to connect everything and can’t hook up half of it because the wrong cables were installed. That just makes it more expensive than having a professional handle it from the start.

Hello KNX-Partner,

I didn’t say that! Of course, these details are discussed with the electrician beforehand. It worked that way for my parents. Personally, I would have it done by a professional!

Best regards

K.Brodbeck

Hello KNX partner,

I didn’t write that! Of course, you should discuss this with the electrician in advance. That’s how it worked for my parents. Personally, I would have it done by a professional!

Best regards,

K.Brodbeck

Okay, then I have nothing to say. I just wanted to point out the risks if you do it yourself. Unfortunately, there are quite a few people who take electrical installations lightly just because they have seen a switch being installed before. You should always remember that a faulty electrical installation poses a risk to life and limb. However, if an expert is available for advice and guidance, then it’s all fine.

Regards, Sven