Missing Jumpers on K1, K2, and K3 Contactors in Yaskawa Bypass Units
Topic Description

The 1000 series bypass units and later 7 series bypass units have either wire jumpers or bus bar jumpers on the K1, K2 and K3 contactors. These jumpers are used to provide power between contactors.
Resolution

On certain bypass models, Yaskawa uses a very thin bus bar to jumper power between contactors. This bus bar is difficult to see as it blends in with the terminals and may appear the contactors are not connected to each other. 

The picture below is an example of a bypass model with a bus bar connected between contactors. 

To verify the bus bars are installed:

  1. Turn OFF power to the cabinet
  2. Ensure continuity on the input of K1 and K3 on all phases. 
    Note: K1 contactor is not available in all Yaskawa Bypasses. 
  3. Ensure continuity on the output of K2 and K3 on all phases. 

Example of a contactor bus bar UWR-0633 (LA9D65A6):
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Replacing the Contactor, Overload Relay, Jumper or Din Rail in E7B, E7L, E7N & P7B panels

Product Types
HV600 Bypass, E7B Bypass, E7BR, E7BR Bypass Nema 3R, E7L Bypass, E7N Bypass, E7S Slim Configured, P1000 Bypass, P7 Bypass, Z1000 Bypass, Z1000U Bypass,
All Applications
Advanced Random Rotary Knife with Cam Blend, Air Compressor, Blister pack Thermoformer, Cartoner, Centrifuge, Conveyor, Crane/Hoist, Dynamometer, Elevators and Escalators, Extrusion, Fans/Blowers, Feed To Length, General Machinery, HVAC, Irrigation, Labeler, Laundry, Linear Flying Shear, Machine Tool, Mixer, Other, Packaging, Palletizer, Precision Grinding, Pump, Punch Press, Rotary Knife, Rotary Placer, Rotary Table Indexer, Screw Feeder, Semiconductor, Solar Cell Tabbing and Bussing, Solar - Textured Etching, Synch-Belt, Textile, Winding,
Last Modified Date: 08-18-2022ID: 12661