These 2 pin pluggable connector is used on our hotend whip. You'll need one of these if you are making your own wiring harness or repairing an SE300.
Installing a replacement hotend power connector on a stock SeeMeCNC printer:
1) power off machine
2) note black and red wire positions, then cut off existing connector
3) strip just less than 1/4" (6mm) of each wire
- pull wire strippers straight
- DO NOT twist strands of wire
4) insert tiny flat screwdriver into rectangular slot of pluggable connector to release the gripping mechanism
5) pushing straight, push in the correct color wire into corresponding hole until the insulation of the wire recesses into the pluggable connector. No bare wires or stray strands should be protruding. Repeat for both wires.
6) check for short circuit, then plug into the hotend