In-line continuity test for manufacturing hairpins

Quality check of each hairpin manufactured

Manufacturing hairpins is a demanding process and the strong bending push the enamel to the limit.

To make sure no hairpin is leaving the manufacturing line without individual test of each item is the way to go.

Knowing the quality of the wire before wire processing is possible by adding pre-test.

High Voltage Continuity Tester (HVC), for detection of enameled wire which is not coated 100% or has cracks or pinholes. Read more about pin-hole detection here

Blisters on the surface of the wire also causes problems and have a big impact on the quality of the Hairpin and the final Stator.

Read more about blister detection here

Our HVC 360 SA - designed specific for Hairpin producers


  • Simple in installation 
  • Operates without PC
  •  Settings directly on unit
  •  Analog interface for PLC
  •  LED indicators on front
  •  Detected fault output signal
  •  Tailor made for end users of wire

The new HVC 360 SA measuring head offers the end user of wire a effective way to detect defects as pin-holes or cracks in the insulation of the wire before starts processing.

Hairpin Winding

Adding this measuring head before winding a stator, rotor, coil, transformer, hairpin etc. secures the final product is not turned into scrap due to missing or insufficient insulation of the wire. Checking missing overlap for wrapped wire is possible too.


How is it possible to test hairpins for electric motors?

The possibilities of testing hairpins for electric motors are continuously developing, and DSE Test Solution is at the pole position when it comes to quality and technology within this field.

We use our HVC Stand-alone, with our special designed electrode tops with conductive brushes, to test every single hairpin to ultimately lower the amount of scrap and time wasted. Our HVC system will measure even the tiniest cracks and faults in the enameled wire and is often built in as a part of an automated system.

Why and when should we test the hairpins for our electric motors?

With our HVC test system, we are able to test and ensure the quality at the most critical and appropriate time in the manufacturing process, saving time, scrap and costs. No hairpin will leave the production line without being individually tested and approved / discarded. This will ultimately make it a more efficient process and provide documentation that the hairpins are approved.

Is it possible to test I-pins with DSE’s test solution?


To make sure we cover all the areas of testing enameled pins, we have also developed a system that can be added to our electrode tops for hairpins. This add-on will create a gap between the brushes and electrode top, where the uninsulated area of the I-pin can run through, without the brushes testing that specific area. In that way, the system only tests the insulated area of the I-pin for faults and cracks. Therefore, it is an effective solution for testing I-pins in an automated process.

Full control from PLC - no PC needed

PLC control of HVC for hair pins

When having many winding machines running with different applications a PLC control is a more practical way of controlling and outputting data. Direct access to detected fault output makes it also possible to stop the winding process or do a marking of the wire. 

Simple in installation and simple in operation.

Only 24 VDC is needed. The setting of the High Voltage and Threshold is done on the front by means of five individual pre-sets (other pre-sets can be made on request) or analogue interface [0.. 10 VDC] for make settings and fault current measurements.

Features of the HVC measuring heads:

 HVC measuring heads for hair pins

  • Full 360 degree surface coverage of the wire
  • Build in controller with 5 individual pre-set for both the High Voltage tension and Threshold
  • Interface for PLC, direct setting of HV and Fault current/Threshold from [0.. 10 VDC]
  • Output for measured fault current
  • Wide range of electrodes available from wire size 8 µm to a completed bended “hairpin”
  • Optical isolated output when fault is detected.
  • Output for switch on light tower (Power ON & High Voltage ON)
  • No damage from sparks (low power design)
  • Wide output test Voltage range 350 VDC to 6000 VDC
  • Low tension means no damage of the enamel because of the very soft conductive brushes

We at DSE Test Solutions use the feedback from our clients and from the market to develop our solutions. Feel free to browse our website and find out more in the datasheet, and if you’re worried that we might not have a solution for your setup – please contact us and we will do our very best to use your feedback as fuel for further development.

Download the datasheet here

Read our case here

Read more here:

  English version   Deutsches Version

HVC SA UK Version HVC SA Deutshes Version