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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Sourcing notes for custom parts
Drawings, tooling, quality and landed cost, from the team that runs the programmes.
All guides, page 21
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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.
Read
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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Sourcing9 min read
Supplier payment risk in India: due diligence and security
How to check a supplier before money leaves your account, structure the payment so a failure is survivable and keep monitoring after the first order.
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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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Contacts10 min read
Contact design for MCBs and MCCBs: what changes with frame size
A miniature breaker and a moulded case breaker share a job but not a contact system. A guide to force, arc control, material and calibration.
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Contacts9 min read
Contact design for switches and sockets: force, wipe and arc
A wall switch and a socket outlet look simple and fail for different reasons. The contact calls that decide life, temperature rise and plug retention.
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Contacts9 min read
Contact erosion and arc damage: life drivers and design responses
How arcing removes and transfers contact material, why make and break do different damage, and how to size an erosion allowance.
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Quality9 min read
Electrical conductivity testing: methods and interpretation
A conductivity number is meaningless without the method, the temperature and the direction of measurement. Here is how to read the result and when to ask for a test.
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Contacts9 min read
Coil bobbin design: wall thickness, creepage and retention
The bobbin is the coil's structure, its insulation and its interface to the assembly. Small geometry calls decide all three.
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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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