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I see that 'normal' relays generally have shorter opening than closing times (see for example: http://www.langirele.com/pdf/pcb-relay-T73.pdf). Do reed relays also have shorter opening than closing times? If so, typically by how much?

I am interested in this for the W171DIP-25 (http://www.mouser.com/ds/2/357/105A_117SIP_107DIP_171DIP-6475.pdf) reed relays.

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  • \$\begingroup\$ Use SSR if you care open/close time. Opening force big because need dominate spring. \$\endgroup\$ – dsgdfg Apr 11 '16 at 8:30
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Yes, generally, especially if you drive the relay so as to have the opening time minimized. Here is a datasheet from a similar series of three models of reed relay (the one on the far right, where release is slower, is a SPDT type):

enter image description here

The drive method for the specified typical opening time of 200usec is a 56V Zener diode series with a 1N4148 across the coil, so you'd want to use at least a 60V transistor to drive it.

If you just slap a diode across the coil, of course you can expect the release time to be considerably longer.

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  • \$\begingroup\$ When you say "considerably longer", about how much longer is that? My reed relays come with built-in diodes. \$\endgroup\$ – dpdt Apr 10 '16 at 23:50
  • \$\begingroup\$ Suggest you contact the manufacturer or take 10 minutes and test it- it will vary depending on the reed relay design. WAG is 1.5-2:1, but don't depend on that. \$\endgroup\$ – Spehro Pefhany Apr 10 '16 at 23:59

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