Rating:  The curves on the rating graph represent the maximum unbalance of weld currents expressed in percent (%), which the weld current equalizers can balance as a function of the maximum secondary voltage available from the welding transformer.  The process of determining the required rating is shown in the following examples.

Example 1

  • Maximum Secondary Voltage 7.5 Volts
  • Welding Current in Loop 1 15,500 A
  • Welding Current in Loop 2 14,000 A
  • Unbalance 15,500-14,000 = 1,500 A
  • % Unbalance 1,500 / 14,000 X 100 = 10.7%*
  • From Rating Curve: Use RWE 7/15

Example 2

  • Maximum Secondary Voltage 11.5 Volts
  • Welding Current in Loop 1 16,200 A
  • Welding Current in Loop 2 18,400 A
  • Unbalance 18,400-16,200 = 2,200 A
  • % Unbalance 2,200 / 16,200 X 100 = 13.6%*
  • From Rating Curve: Use RWE 12/15

*NOTE: the percent unbalance must  be based on the lower weld current representing 100%

Rating Graph
Selection
  1. Determine maximum secondary voltage of the transformer used and locate voltage on rating graph
  2. Determine % unbalance
    a.  For existing installations, use data from actual measurements.

     See examples under Rating.
    b.  For new installation, assume % unbalance from prior

     experience, generally between 10 to 15%.
  3. Bring voltage and % unbalance to intersect on rating graph, select RWE 7/15 series equalizer for points to the left of curve marked RWE 7/15.  Select RWE 12/15 series equalizer for points falling between curves marked RWE 7/15 and RWE 12/15
  4. Determine secondary lug configuration of transformer used.
    RWMA inline Lugs (Bulletin F-1, F-3)
    RWMA staggered lugs (Bulletin F-2.1, F-4)
    RoMan staggered lugs (Bulletin F-2, F-4)
  5. Select the model number of the weld current equalizer from the selection table using the appropriate columns determined in Steps 3 and 4

Selection Table

Equalizer Rating From Step 3 Transformer Secondary Lug Configuration from Step 4 Model Number Weight (LBS) DWG

RWE 7/15
RWMA Inline Secondary Lugs
RWMA Staggered Secondary Lugs
RoMan Staggered Secondary Lugs
RWE 7/15A-1689
RWE 7/15E-1691
RWE 7/15B-1690

19

R1959

RWE 12/15
RWMA Inline Secondary Lugs
RWMA Staggered Secondary Lugs
RoMan Staggered Secondary Lugs
RWE 12/15A-1668
RWE 12/15E-1670
RWE 12/15B-1669

24

R1959