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I have a new hob (magnetic induction plate). It requires 7200W/32A. The power grid's voltage is 230V (Europe).

I have already installed a thick cable and I want to use it (it would be difficult to change it). But I don't know its diameter (and at the moment no tools to measure it) but it seems to be about 1.5mm or rather 1.75mm diameter. The cable is about 3meter long and it says:

CableTeam    VDE    HAR    HD 5VV-F    301.5

What is the max amp for this cable?

I will run this cable in the back of the over. There is a 6-9 cm space between the oven and the wall. And the oven has its own cooler. The temperature in the back of the oven stays relatively low (about room temp).

enter image description here

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    \$\begingroup\$ Can you post a pic with something we can use for scale? Thar would help, as well as knowing some things about its intended use (like if its use will be subject to regulatory codes; how long a run it will be making; what temperatures will it be working in & what temperature rise are you willing to allow in the wire) \$\endgroup\$ – Robherc KV5ROB Feb 3 '16 at 9:55
  • \$\begingroup\$ Max amp under what environmental conditions? What is the maximum temperature rise tolerable in your case? How much heat can you transfer away from it? \$\endgroup\$ – PlasmaHH Feb 3 '16 at 10:07
  • \$\begingroup\$ Is that actually "301.5" or "3G 1.5"? Most cables have the number of cores and cross-sectional area printed or stamped onto them. A 1.5 sq.mm cable isn't going to be anywhere big enough for 32A. \$\endgroup\$ – Simon B Feb 3 '16 at 11:00
  • \$\begingroup\$ @SimonB - it is "301.5". The diameter seems to be about 1.5mm-1.75mm. \$\endgroup\$ – Ultralisk Feb 3 '16 at 11:02
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    \$\begingroup\$ I know that this wasn't asked in the question, but please do check that the rest of your installation can actually support such current. In my part of Europe at least, something running that power would usually go with a 3-phase installation. \$\endgroup\$ – AndrejaKo Feb 3 '16 at 12:32
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To give you some reference, here in the US #10 cable is usually allowed to carry up to 15-30 A use in homes. A solid #10 cable is 2.59 mm in diameter. Your cable looks to be around 2 mm or maybe a bit less, which is close to #12 (2.05 mm diameter).

Keep in mind that the current rating of a cable is someone's judgement call. For example, the same #10 cable is allowed over 50 A in "chassis wiring". This is all about the probability of the cable getting hot enough to ignite something, and the consequences of that. Inside a metal chassis, there is much less of a safety issue due to a hot cable than when it runs against dry wooden supports inside walls in a house.

You can certainly get 32 A thru the cable you show. There are then two things you have to decide:

  1. Is the voltage drop tolerable for your application?

  2. Is the resulting cable temperature still safe in your application?

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I would just like to add that measuring cable diameter by ruler is probably not the best method , since you are interested in cross sectional area rather than diameter.

when you hear someone saying a 2mm cable , he actually means 2mm2 cable .

There are charts that contain the recommended current per cross sectional area. but most of them are for long distance power transmission so they are conservative ratings.

The best way of solving this problem is getting the resistance per meter of you specific cable and finding the power loss and voltage drop as Olin said.

use P(loss heat)=IxIxR and V(drop)=RxI.

Cable resistance chart in metric units

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