A jumper is a tiny metal connector that is used to close or open part of PCB manufacturing. It may be used as an alternative to a dual in-line package (DIP) switch. A jumper has two or more connecting points, which regulate an PCB and adjust the on-off relationship of different electrical signals on the equipment,so as to regulate the equipment working state, like ensuring the motherboard voltage, numbered drives and etc.
1、 Jumper wires should be routed in an X-Y manner as directly as feasible, making as few bends as possible. Direct routing aids organization, saves material, etc. - simpler and shorter enhances reliability.
2、 Bare conductor jumper wires longer than 12.7 mm (0.50") should not be used. Bare conductor jumper wires shorter than 12.7 mm (0.50") should not violate the minimum electrical clearance (the 12.7 mm (0.50") dimension refers to the length between terminations).
3、 Jumper wires shall not be routed under or over component leads or component bodies. Contact with heat sinks must be avoided. The reason is simple; components may need to be reworked, and they cannot be reworked effectively if access is blocked by jumper wires. Heat sinks may melt wire insulation and result in shorts.
4、 Jumper wires should include a stress relief. Thermal expansion and mechanical stress affect all components including jumper wires. Adding a bit of slack near the termination point is all that is needed. As an added note, you should avoid very tight bends in jumper wires. Avoid bending the jumper wire tighter than a radius of 3 times the conductor diameter.