I'm shopping for reed contacts that are rated for 230V AC, because I don't want to use an always-on power supply just for a relay and a reed switch. This is surprisingly difficult, but I found this product:


reed contact

In the description it says:

Note: The multimeter can not be used to test the opening and closing of the door switch.

What does that tell me about the inner workings of this thing?

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    \$\begingroup\$ It sounds a bit chinglishish but it might mean that the contacts have a minimal wetting current. Bottom line: never buy things without a proper datasheet. \$\endgroup\$ – PlasmaHH Sep 17 '18 at 9:32
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    \$\begingroup\$ A datsheet is like a CV, without a CV no one would hire you, without a datsheet you shouldn't buy it. Common sense. \$\endgroup\$ – Harry Svensson Sep 17 '18 at 9:35
  • \$\begingroup\$ The specifications in that particular listing are about 5 times more detailed than you can find on typical magnetic door switches. See this pathetic excuse for datasheet, for example. But yes, I agree that this is most likely a reference to wetting current. Common for reeds since mercury wetting has been banned \$\endgroup\$ – Maple Sep 17 '18 at 10:42
  • \$\begingroup\$ Has anyone seen a reed switch operated thyristor that is encapsulated? They would also fail testing at low voltages and DC. \$\endgroup\$ – KalleMP Sep 18 '18 at 12:10

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