Warm cable is that a problem?

DIY
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I have two 70mm2 cables that goes from my Multiplus in to a switch and then out from the switch with one 120mm2 cable to the Lynx distrubator.
And when I charge at 90A the two 70mm2 cables only get slightly warmer than room temp but the 120mm2 gets a slightly warmer. I can still hold my hand and on it, not so hot it burns.

Is smart to change that one 120mm2 to two 70mm2 also…?
Or is it no problem that it get slightly warm.

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120mm2 for only 90A on such small length and it gets warm?
Strange…
I have the feeling that the source of heat is not the cable itself, but the switch internals.
And the heat is just propagating to the cable.

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Would help to make a infrared image of this to see where the hotspot is.

Maybe a bad crimped end of the 120mm2 wire or a bad contact at the fuse?

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I expect that a thermal image of the setup will show that the heat might be generated in the battery switch. It’s quite common that the switch contacts can get warm with high continuous currents. This heat is transferred to the connected cables.

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@Dailycamper
From my point of view your heating problem on 120mm² comes from the fact that the terminal that is in contact with the fuse is too big. Let me explain, look at the contact surface of your fuse and that of the terminal, it is almost 1 for 2 so the juice arrives on the terminal but it is in a bottleneck from the fuse.
I advise you, if you want to keep this 120mm² to connect it on the side of the Lynx, its contact surface will be much better (positive and negative of course), on the other hand this means that you have to locate your fuse (and/or disconnector) elsewhere. You will no longer have the fuse LED indication from the Distributor either.
You can also try to connect your disconnector directly on the side but Distributor in M8 and your disconnector must be in M10, it’s up to you…