Contacts10 min read
Coils for motor windings
Distributed, concentrated and hairpin windings do the same electrical job in different ways. How the choice changes end turns, harmonics, slot fill and the cost of a stator.
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Sourcing notes for custom parts
Drawings, tooling, quality and landed cost, from the team that runs the programmes.
All guides, page 22
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Contacts10 min read
Contact material selection for AC vs DC switching
An AC arc gets a current zero every half cycle. A DC arc does not. That single difference reshapes erosion, welding and the material shortlist.
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Contacts9 min read
Contact plating: silver, gold and nickel compared
The finish on a contact decides its resistance, its wear life and its cost. A practical comparison of silver, gold and nickel, and the underplate that holds them together.
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Contacts9 min read
Contact welding and sticking: causes and prevention
Why closed contacts fuse, which loads make it worse, and the material, force and circuit changes that keep a contact opening.
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Quality9 min read
Vibration and shock testing
Sine, random and shock profiles answer different questions. Pick the one that matches the service load, then fix the mounting and the acceptance check before the first run.
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Contacts10 min read
Coils for transformers and inductors
Turns ratio, winding window, insulation and loss: the four calls that decide a transformer or inductor coil, and where the two designs part company.
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Contacts9 min read
Contact brazing and welding: how to choose the joining process
Resistance welding, brazing and laser welding each leave a different joint, a different heat affected zone and a different inspection problem. Match the process to the contact, the carrier and the life target.
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Contacts9 min read
Contact resistance: what it means and how to test it
Constriction and film resistance, the four-wire method, and why a single micro-ohm reading is a weak acceptance criterion.
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Contacts9 min read
Copper wire for coils: enamelled grades and temperature classes
How enamel grade, temperature class and winding practice decide whether a coil survives its own heat.
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Quality9 min read
Thermal cycling and humidity testing
Temperature and moisture find the joints, seals and interfaces that a room-temperature check cannot. The value is in the profile, the inspection and the acceptance rule, not the chamber alone.
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Contacts10 min read
Coils for relays and solenoids
Force, stroke and heat decide a coil long before the wire gauge does. A guide to the ampere-turns, duty and thermal calls that separate a relay coil from a solenoid coil.
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Contacts9 min read
Contact assemblies: bimetal and trimetal layer choice
The contact face does the switching, but the layers behind it decide the joint, the heat path and the cost. How to choose a bimetal or trimetal stack and specify it on a drawing.
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Go from reading to checking
The guides are built around the same questions as the free tools. Size a busbar, check an ISO 2768 callout, build a first article report or compare landed cost.
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