Manual

ULTRA-CUT 100 XT
Manual 0-5303 INSTALLATION 3-7
A. Electromagnetic Interference (EMI)
Pilotarcstartinggeneratesacertainamountofelectromagneticinterference(EMI),commonlycalledRFnoise.This
RFnoisemayinterferewithotherelectronicequipmentsuchasCNCcontrollers,remotecontrols,heightcontrollers,
etc.TominimizeRFinterference,followthesegroundingprocedureswheninstallingmechanizedsystems:
B. Grounding
1. Thepreferredgroundingarrangementisasinglepointor“Star”ground.Thesinglepoint,usuallyonthecutting
table,isconnectedwith1/0AWG(European50mm
2
)orlargerwiretoagoodearthground(measuringless
than3ohms;anidealgroundmeasures1ohmorless.Refertoparagraph‘C’,CreatingAnEarthGround.The
groundrodmustbeplacedascloseaspossibletothecuttingtable,ideallylessthan10ft(3.0m),butnomore
than20ft(6.1m)fromthecuttingtable.
NOTE
All ground wires should be as short as possible. Long wires will have increased resistance to RF fre-
quencies. Smaller diameter wire has increased resistance to RF frequencies, so using a larger diameter
wire is better.
2. Groundingforcomponentsmountedonthecuttingtable(CNCcontrollers,heightcontrollers,plasmaremote
controls,etc.)shouldfollowthemanufacturer’srecommendationsforwiresize,type,andconnectionpointloca-
tions.
 ForThermalDynamicscomponents(exceptRemoteArcStarterandGasControlModule)itisrecommended
touseaminimumof10AWG(European6mm
2
)wireoratcopperbraidwithcrosssectionequaltoorgreater
than10AWGconnectedtothecuttingtableframe.TheRemoteArcStarteruses1/0earthgroundwireandthe
GasControlModuleshoulduseminimum#4AWGwire.Theconnectionpointmustbetocleanbaremetal;
rustandpaintmakepoorconnections.Forallcomponents,wireslargerthantherecommendedminimumcan
be used and may improve noise protection.
3. Thecuttingmachineframeisthenconnectedtothe“Star”pointusing1/0AWG(European50mm
2
)orlarger
wire.
4. Theplasmapowersupplyworkcable(seeNOTE)isconnectedtothecuttingtableatthesinglepoint“Star”
ground.
NOTE
Do Not connect the work cable directly to the ground rod. Do not coil up excess ground or power cables.
Cut to proper length and reterminate as needed.
5. Makesureworkcableandgroundcablesareproperlyconnected.Theworkcablemusthaveasolidconnec-
tiontothecuttingtable.Theworkandgroundconnectionsmustbefreefromrust,dirt,grease,oilandpaint.If
necessarygrindorsanddowntobaremetal.Uselockwasherstokeeptheconnectionstight.Usingelectrical
jointcompoundtopreventcorrosionisalsorecommended.
6. Theplasmapowersupplychassisisconnectedtothepowerdistributionsystemgroundasrequiredbyelectrical
codes.Iftheplasmasupplyisclosetothecuttingtable(seeNOTE)asecondgroundrodisnotusuallyneeded,
in fact it could be detrimental as it can set up ground loop currents that cause interference.
 Whentheplasmapowersupplyisfarawayfromthegroundrodandinterferenceisexperienced,itmayhelpto
installasecondearthgroundrodnexttotheplasmapowersupply.Theplasmapowersupplychassiswould
then be connected to this ground rod.
NOTE
It is recommended that the Plasma Power Supply be within 20 - 30 ft (6.1 – 9.1 m) of the cutting table,
if possible.
7. Theplasmacontrolcableshouldbeshieldedwiththeshieldconnectedonlyatthecuttingmachineend.Con-
nectingtheshieldatbothendswillallowgroundloopcurrentswhichmaycausemoreinterferencethanwithno
shield at all.