D. Sensing Leads Placement Guidelines For Multiple Arcs
Trail
Trail
Work
Clamp
Trail
Trail
Remote Voltage
Sense Leads
Remote Voltage
Sense Leads
Lead
Work
Clamp
Trail Lead
Remote Voltage Sense Leads 
Lead
Remote Voltage
Sense Leads 
Work
Clamp
Lead
Remote Voltage Sense Leads
Remote Voltage
Sense Leads
Lead
Work
Clamp
Trail Lead
Lead
Welding Power
Source
Trail
Welding Power
Source
Lead
Welding Power
Source
Trail
Welding Power
Source
Lead
Welding Power
Source
Trail
Welding Power
Source
BAD
Current flow from lead affects trail sense.
Current flow from trail affects lead sense.
Neither sense lead picks up the correct work voltage, causing starting and welding arc instability.
BETTER
Lead sense is only affected by weld current from lead.
Trail sense lead is only affected by weld current from trail.
Due to voltage drops across work piece, arc voltage may be low, causing need for deviation from standard procedures.
BEST
Both sense leads are out of the current paths.
Both sense leads detect arc volt- age accurately.
No voltage drop between lead and trail sense.
Best starts, arcs and most reliable results.
Ref. 804
