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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Topic hub
Contacts, coils and electromechanical
Contacts and coils sit at the point where electrical performance becomes physical. These guides cover material choice, contact resistance, arc damage, winding, termination and the tests that prove a switching part will last.
Guides in this topic, page 3
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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Contacts9 min read
Contact RFQ checklist: what to send for a comparable quote
A contact price depends on the load, the material, the joint and the test. Send all four in one pack, or the quotes will not be comparable.
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Contacts9 min read
Silver cadmium oxide vs silver tin oxide: performance and regulation
The cadmium-free switch is not a straight material swap. What changes in resistance, welding and erosion, and what to revalidate.
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Contacts10 min read
Coil impregnation and encapsulation
How varnish and epoxy change the thermal path, the mechanical support and the life of a wound part, and how to specify the process without overbuilding the coil.
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Contacts9 min read
Contact cost drivers: silver price and scrap recovery
The silver in a contact is a traded metal, a process input and a recoverable asset at the same time. The quote has to treat it as all three.
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Contacts9 min read
Silver tungsten vs silver nickel contacts: how to choose
Two workhorse contact materials with opposite strengths. A comparison of resistance, erosion, welding and the force each one needs.
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Contacts9 min read
Sourcing contacts and coils from India: capability, silver and export
Contacts and coils are specialist products, not catalogue parts. What the Indian supply base can do, how silver is handled and what to verify before a programme moves.
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Contacts10 min read
Coil insulation classes: B, F, H and beyond
What a thermal class actually rates, how hot spot temperature differs from the average winding rise, and how to choose a class without paying for margin you do not need.
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Contacts9 min read
Contact FAI and material certificates: what the pack should contain
A contact first article pack links the drawing, the material, the joint and the test result to one serial number. Here is what to ask for.
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Contacts9 min read
Contact tips and pads: silver content, backing and joining
What silver content actually changes, why the joining method decides the joint more than the grade does, and how to specify a tip that stays on the blade.
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Contacts9 min read
Electromechanical assemblies: contact, coil and housing integration
A relay, contactor or actuator is only as good as the interfaces between its coil, its contacts and its housing. Where the tolerance chain is set and how to test across it.
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