Can I parallel two phase wire with same polarity but with difference cable size ?

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meowsoft

Joined Feb 27, 2021
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Can I parallel two phase wire with same polarity but with difference cable size ?, 16mm2 and 25mm2, also 16mm2 capacity is 80a, and 25mm2 capacity is 105a
1. Can I use that wire in parallel with 2 pole MCB rated at 80a ?, load is 180a
2. Can I use that wire in parallel with 2 individual MCB one rated at 80a, and one rated at 100a ?, but MCB handle is mechanically joined together, is that safe ?, load is 180a
3. Use that 16mm2 wire and 25mm2 wire in parallel, load is 172a, and current is limited with same scenario with number two, 80a and 100a MCB, also after two individual MCB, also used programmable MCB that limited current to 172a
Can difference resistance make problem ?, 25mm2 resistance is 0.524, 16mm2 resistance is 0.727, resistance ratio, is 1 : 1.38, and expected current to passed is 1 : 1.25, can this resistance make 25mm2 cable overloaded ?, I think with scenario number two 25mm2 cable can be overloaded and 100a MCB can trip so much, and with scenario number one I think also 25mm2 MCB can be trip so much, because 25mm2 wire resistance is lower and can attract more current to passed through 25mm2 cable than 16mm2 cable, but with scenario number three, with that resistance ratio I think 25mm2 wire can attract about 100a in 25mm2 wire, 16mm2 wire can attracted about 72a through their resistance, also not overloaded that wire capacity and MCB, is that's true ?, and is scenario number three possible ? please clarify if I am wrongView attachment 234925
Scenario Number Three see at picture
 
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