Hot power cord connector

I just finished the assembly of my MPCNC. I am using a Rambo board with LCD. I noticed after the power was on for a few minutes that the provided 12V power connector was getting really warm. Is this normal?

The recommended assembly is to snip off the connector on the power supply end, and wire it to the control board (no connectors). The connector getting warm is concerning, very concerning if it is happening with the steppers off. It is happening because there is resistance that should not be there somewhere in that connection.

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No warm means resistance. Resistance is like when the hose balloons. You do nor want heat with power.

OK. Thanks!
Heat bad and cut the cord.

Some barrel jacks are rated to be able to handle an mpcnc, but most are limited to 1A or so. Also I have lost count of the number of knock off phoenix conn style screw connectors that had black solder joints to the pcb from the usual factories. I’d definitely do as Robert suggested, and hack the brick so the wires go directly to the board.

For years I would just jam wire into screw connectors and crank the screw down, or if I was feeling particularly careful, would solder the end of the wires before inserting them. Then from reading this forum I found this was a bad practice. The right way is to use ferrules. I’d never heard of ferrules before reading about it here, but I have a kit now, and I use them for all screw terminal connections. I suspect the heat is coming from a bad screw connection, though Kev may be right that the connector is just not rated for the 5A used by the MPCNC.