Wrong Cables/Shunts

Definition 

The weld is not correctly made due to the use of an incorrect cable or shunt.

Description 

Cross Sectional Area: 

  • Too small: Current flow is restricted due to the increase in impedance. 
  • Too large: Conductor stiffness can cause problems in properly locating equipment; premature wear to the machine components; or achieving weld force. 

Conductor Length: 

  • Too long: Current flow is restricted due to the increase in impedance; proper weld placement can be hindered by cable drag and entanglement; short circuits may result from the above conditions. 
  • Too short: Inadequate length can cause problems in properly locating equipment; premature wear to machine components; or achieving required weld force.

Detection 

Detection evidence may include: 

Significance 

Quality, Workplace Issues, Cost, Downtime, Maintenance, Throughput (cycle time; PPH), are all potentially affected by this condition. Special considerations are noted below:

Quality: Cables that are improperly sized can cause variations in welds from operator to operator in manual operations. 

Subordinate Causes

  • Correct conductor not immediately available. 
  • Increase in jobs per hour, weld current, or weld time requirements.