Can someone tell me where affordable and easy to find 12VDC light duty DPDT latching relays can be purchased?I’ll need two dozens of these for a project I have in mind.They’ll only be used for powering LED’s and/or micro sized lamps so would be expected to last but I’d like them to be popular and easy to find should one fail.Thanks.
Just in case no one comes up with a source for you, you can make your own latching operation.
Simply buy a relay with one spare pole and use it to power it’s own coil. Wire around the pole with a NO momentary switch to activate and a NC momentary in series with the coil to deavtivate.
Quick visio drawing below.
I’ve used dozens of them myself for controlling signals. I got mine from DIGIKEY. They are DPDT type latching and are available in 5 / 12 / 24 / 48 volt operation. The 12 volt part number is 255-1067-ND. They are a 16 pin ic socket variety which comes in handy if you need to replace a bad one - pop out the bad one, plug in a replacement ! They’ve shipped my order to me within two days, and I live in Canada too !!! Their web-site is http://www.digikey.com/
Mark.
Look under :“relays” at www.allelectronics.com and take your pick.
FYI on these things - I’ve used them in parallel with my twin-coil turnout machines to provide contacts for indicator LEDs and signals. I use a capacitive discharge system, which provides DC to the coils and relays. While your switch machines will work on either AC or DC, these low-cost relays are generally only going to work on DC.
Also, unlike switch machines, they can be polarity-sensitive. They will throw the other way if you reverse the polarity of the input voltage.
Good idea. This is used in low & medium voltage (i.e. 208-575V for LV and 2.3-15kV for MV) motor control…the spare contact used to “seal-in” the coil is called a seal in contact…either a “stop” command or a trip from the overload relay with drop out the contactor’s coil…