8EMC AND LOW VOLTAGE DIRECTIVE

8.1.4 Power supply module

MELSEC-Q

Always ground the LG and FG terminals after short-circuiting them.

8.1.5When using QA1S6 B type base unit

(1)Cable

(a)Earthing of shielded cable

•Earth the shield of the shielded cable as near the unit as possible taking care so that the earthed cables are not induced electromagnetically by the cable to be earthed.

•Take appropriate measures so the shield that was partly removed for exposure is earthed to the control panel over a large contact surface area. A clamp may also be used as shown in the figure below. In this case, however, apply a cover to the painted inner wall surface of the control panel which comes in contact with the clamp.

 

Screw

Shield section

Clamp fitting

 

Paint mask

 

Shielded cable

Note) The method of earthing by soldering a wire onto the shield section of the shielded cable as shown below is not recommended. The high frequency impedance will increase and the shield will be ineffective.

Shielded cable

Wire

Crimp terminal

8 - 5

8 - 5