PURPOSE: To perform insertion and removal of a printed circuit board without stopping the nitride operation when pulling out the printed circuit board from a back panel by providing a short-circuit connector free for insertion and removal between a power receiving pin connected to the power source side and a power supplying pin connected to the supply side.
CONSTITUTION: A power supply pattern 12, which is connected to the power source wiring 11 from a power source unit 10, is stretched at the rear 1A of a back panel 1, and a short-circuiting connecter 7 is attached to the power supply pattern 12, corresponding to the rear where a printed board 2 is mounted. The mounting of a short- circuit connector 7 is done being set between a power receiving pin, which is projected to the rear 1A by piercing the power supply pattern 12, and a power supply pin 9, which is projected to the rear 1A by piercing a power source pattern 15, and by setting of a short-circuit connector 7 the power supply pattern 12 and power supply pin 9 are connected. Thereupon, power supply to each printed board 2 is made by the power supply pattern 12 being connected to the power receiving pin 8 via the power source wiring 11, and the power receiving pin 8 being connected to a power supply piston 9 through the short-circuiting connector 7, and further the power supply pin 9 being connected to the power source pattern 15, and the specified pin 5 being connected to the power source pattern 15.
