Contacts9 min read
Coil RFQ checklist: turns, wire, bobbin, termination and test
A coil quote moves with every open variable. The pack that closes the winding, the bobbin, the termination and the test before a supplier prices the part.
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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 4
Contacts10 min read
Coil winding: layer, bank and random winding
How the winding pattern changes fill, capacitance, leakage and cost, and how to choose a pattern before the bobbin is designed.
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Contacts9 min read
Contact inspection: silver content, hardness and shear
Three checks that separate a contact which meets the drawing from one that only looks right, and how to read each result.
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Contacts9 min read
Electrical contact rivets: materials, head design and staking
How a composite rivet separates the electrical duty from the mechanical joint, and the drawing calls that decide whether it survives life test.
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Contacts9 min read
Overmoulded coils and sensors
Sealing, strain relief and melt flow decide whether an overmould protects a winding or quietly damages it. Here is how to control all three.
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Contacts9 min read
Coils for sensors and antennas
Frequency, Q factor and stability decide whether a sensor coil measures the target or the weather. Here is what to specify and how to check it.
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Contacts9 min read
Contact plating thickness and porosity
Thickness, underplate and pore count decide whether a contact plating survives corrosion and arc erosion. Measure all three, on the face that carries the current.
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Contacts9 min read
Solenoid assembly: force, stroke and heat
Force at stroke and coil temperature are one problem. A solenoid that passes a cold bench test can still fail in a hot cabinet.
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Contacts9 min read
Relay assembly: critical dimensions and adjustment
Armature travel, contact gap and follow decide whether a relay pulls in, drops out and holds its rating. Here is how the settings interact in production.
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