Contacts10 min read
Coil cost drivers
Wire, bobbin, winding time and test: where the money goes in a wound part, and which design changes actually move the price.
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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
Contacts9 min read
Coil testing: resistance, inductance, hi-pot and turns ratio
Four measurements catch most coil faults, provided each is made at the right point in the build and against a stated limit.
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Contacts10 min read
Contact design for EV relays and battery disconnects
A battery disconnect has to break DC at full current without a natural zero. Precharge, blowout, material and weld detection decide whether it does.
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Contacts9 min read
Contact rivet clinching and staking: process, defects and inspection
The variables that decide joint strength, the defects that hide under a clean staked head, and the checks that catch them.
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Contacts9 min read
What is a coil? Winding types and where each is used
A coil turns current into a magnetic field, or a changing field into current. A plain language guide to the winding families, the cores and the parameters that define a coil.
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Contacts10 min read
Coil FAI and PPAP
A first article for a wound part is more than a dimensional report. What to balloon, what to measure, which process records to collect and how a coil submission differs from a stamped part.
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Contacts9 min read
Coil thermal management: losses, paths and the hot spot
A coil fails at its hottest point, not at its average temperature. The design has to move heat from that point to the ambient.
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Contacts10 min read
Contact design for relays and contactors: low-level vs power switching
A relay may switch microamps or a hundred amps. The contact system, the force and the test change completely. A guide to the four duty zones.
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Contacts9 min read
Contact force and bounce: the two spring calls that decide reliability
How force sets resistance and how bounce sets erosion, with the spring and mechanism changes that improve both without adding cost.
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Contacts9 min read
Contact weld shear test: sample, fixture and acceptance
A shear test is only useful when the specimen, the fixture and the failure mode are defined. How to set up a contact joint test that two labs can repeat.
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Contacts9 min read
Coil inductance and resistance: the design variables that move both
Turns, core geometry, gap and wire size set inductance and resistance together. Change one and the other moves.
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Contacts10 min read
Coil termination: pins, leads and welded tabs
The joint at the end of a winding is where most coil failures start. How to choose a termination, remove enamel properly and prove the joint will hold.
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