Needing Info on Switching Relays

Gogs

I am hoping to switch relays from digital HIGH from a stamp processor and was curious whether·it can be done or need a·FET or not. The·output of the relay is also a digital voltage·12Vdc. I am hoping to switch approx 6 relays with 6·I/O pins from the stamp.

Advice would be greatly apprecited,

Gogs.·

Andy Lindsay (Parallax)

I went shopping for relays for a BASIC Stamp application the other day and found these at www.digikey.com. They are on order, but I have not tested them yet. They are rated for 30 V, 2A, and both appear to have 5 V switching current draws compatible with BASIC Stamp I/O pins.

PB1066-ND
(STANDARD) RELAY TELCOM DPDT LOW PRO 5VDC

PB1116-ND
(LATCHING SINGLE COIL) RELAY TELECOM DPDT 2A 5VDC

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Andy Lindsay

Education Department
Parallax, Inc.

allanlane5

16 mA on the coil? I suppose, if you switched them one at a time, and put in a diode across the coil, that they would work with the BS2 without an additional external driver device. The latching ones especially.

Andy Lindsay (Parallax)

Good point, they could only be done sequentially without the FETs. EFX-TEK uses a Crydom solid state relay (SSR) for their AC apps that only pulls 3 mA.

http://www.efx-tek.com/topics/crydom.html

There's probably a similar 12-24 VDC SSR at Digi-Key for DC.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Andy Lindsay

Education Department
Parallax, Inc.