Compatibility check 1: magnet gap and alignment
For smart contact sensors, record the exact value, standard, measurement, or supported condition behind magnet gap and alignment before checkout. A broad category label does not prove that the selected variant fits. Confirm the manufacturer, complete model, hardware revision, electrical rating, protocol, controller support, included parts, and region rather than assuming similarly named products share limits.
Compatibility check 2: mounting surface and weather exposure
Test mounting surface and weather exposure across the actual fixture, circuit, controller ecosystem, radio path, owner account, and manual fallback—not a product-photo setup. If this smart contact sensors fit depends on a neutral wire, hub, bridge, account, subscription, compatible controller, professional installation, or reliable cloud service, confirm the exact part, service, or behavior as part of compatibility.
Compatibility checks 3 and 4: battery type and radio coverage; tamper, open-duration, and local automation support
For smart contact sensors, battery type and radio coverage and tamper, open-duration, and local automation support are the limiting conditions most likely to surface only after installation. Measure the smallest clearance, weakest connection, least compatible user or device, and the most demanding normal task. Passing an ideal bench test is not enough.
Prove fit in a reversible order
Use this sequence: clean and dry-fit both pieces, verify the closed state across normal movement, name the opening clearly, and test a low-battery alert. Keep labels, packaging, manuals, and the previous system until the product works through normal use and a recovery test. Photograph wiring, measurements, or assembly states that would be difficult to reconstruct.
A failed fit check is a stop signal
Stop when the frame flexes beyond the allowed gap, the location is wet or too hot, or a missed alert would be treated as a security guarantee. Do not repair a fundamental mismatch with unapproved accessories, copied settings, or community anecdotes. Use motion sensors when it meets the job with a clearer compatibility path.