11-443210FEDCBA98765(Factory setting: ON)ONOFF LG (Rear side)(5) Shield ground switch (LG)For communication lines, use a coaxial cable.As coaxial cable is an unbalanced circuit, ground its shield byturning "ON" the shield ground switch.- Make sure to provide a class-3 grounding for the GND terminal of the power supply module.Without grounding the power supply module, the JW-21MN cannot become conductive with theground after turning "ON" the shield ground switch. (See page 7-2.)- Prior to any electric welding around the JW-21MN, take out the coaxial cable from the JW-21MNWhile the coaxial cable is connected to the JW-21MN, any electric welding nearby the JW-21MNwill cause the welding current to the JW-21MN and may damage part of its circuit pattern.SettingConductive between the shield and FGof the JW20/JW20H/JW30HNot conductive between the shield andFG of the JW20/JW20H/JW30HCondition of the JW-21MNONOFFRemarksCoaxial cableJW-21MN JW-21MNTurn "ON" shieldground switchRack etc.Note: In case enoughconductivity is notestablished.Electric welderFGWrap around currentNote:Turn "ON" shieldground switchCoaxial cable Turn "ON" shield groundswitchTurn "ON" shield groundswitch
