Relays and Solenoid switches

[fsaviator]

Hello all,

can someone give me a quick once over on how to wire up my new simworld solenoid switches with my OC Mastercards.  I'm tracking on needing 12VDC and a relay.  I'm looking for a quick wiring diagram that explains:

-what two pins I jumper with a diode
-what two pins I connect 12VDC to
-what two pins I connect the solenoid to
-what pins are input to the Mastercard

I have access to these relays:
http://www.conrad.com/ce/en/product/503078/Finder-361190124001-PCB-Mount-Relay-12Vdc-SPDT-CO
and
http://www.conrad.com/ce/en/product/503811/Omron-G5LE-1-VD-12-VDC-PCB-Mount-Relay-Cube-12Vdc-1-CO-SPDT

Thanks!  While I understand the concept I can't wrap my head around it.

[fordgt40]

Hi Warren

You need relays that are triggered by 5 volts, not 12 volts. The mastercard outputs are 5 volt and have a maximum capacity of 25ma. There are plenty of relays or indeed reed switches that will do the job - look for one that will work off a TTL input (that is well less than 25ma)

Sadly I am just going away and cannot answer your other questions - just did not want you to get the wrong relay. If no-one else answers the wiring diagram, I will when I return

Regards

David

[fsaviator]

Thanks David!  I actually also have the identical relays in 5V too so that is not an issue.

http://www.conrad.com/ce/en/product/503243/Finder-361190054001-PCB-Mount-Relay-5Vdc-SPDT-CO;jsessionid=701ACE0EBFC472321EF3BF7FC768EA46.ASTPCEN26

and

http://www.conrad.com/ce/en/product/503810/Omron-G5LE-1-VD-5-VDC-PCB-Mount-Relay-Cube-5Vdc-1-CO-SPDT

Now I think it makes more sense to me.  Correct me if I am wrong:

Power is supplied to the solenoid from a 12V feed through the switch in the relay.  When the 5V from the Mastercard opens the switch, 12V is interrupted, when closed, the 12V is supplied?

[dc8flightdeck]

Relays are awesome in a sim.  You are correct, depending on the throw pins that you use. Those relays are SPDT (single pole, double throw).  For your 12 volts you have the option to use the normally closed or the normally open pins. This gives you lots of options when wiring a circuit.

For example, I wire relays so the they are not energized when the sim is has the engines in operation, because that is the condition the sim is normally in. For example, if a light is normally illuminated while in flight I would use the normally close pins for that cicuit. If the lights is turned off, then SIOC activates the 5v to the relay which opens (breaks) the 12v  circuit and shuts off the light! 

This makes the relays last much longer, uses less electrical power during flight, and keep the relay from contiuously emitting noise which they do whenever they are energized (this is also the reason some folks prefer using diode switches) . For this reason I recomend you keep them a bit isolated from other wire circuits in your sim.

Normally open (NO) means when the relay is not energized by 5v then the 12 volt is off because the 12v circuit inside is not connected whenever the 5v is off.

Normally Closed (NC) means when the relay is not energized then the 12v circuit through the relay is on because the 12v circuit stays connected so long as 5v is not applied to energize the relay. Placing 5v to the relay would cause the 12v to turn off when you have the 12v connected to the two Normally Closed pins.

This website has good SPDT realy info and diagrams to explane the wire connections, http://www.the12volt.com/relays/relays.asp

Below is the text from the website.

SPDT Relay  : (Single Pole Double Throw Relay) an electromagnetic switch, consist of a coil (terminals 85 & 86), 1 common terminal (30), 1 normally closed terminal (87a), and one normally open terminal (87) (Figure 1).

When the coil of an SPDT relay (Figure 1) is at rest (not energized), the common terminal (30) and the normally closed terminal (87a) have continuity. When the coil is energized, the common terminal (30) and the normally open terminal (87) have continuity.

The diagram below center (Figure 2) shows an SPDT relay at rest, with the coil not energized. The diagram below right (Figure 3) shows the relay with the coil energized. As you can see, the coil is an electromagnet that causes the arm that is always connected to the common (30) to pivot when energized whereby contact is broken from the normally closed terminal (87a) and made with the normally open terminal (87).

When energizing the coil of a relay, polarity of the coil does not matter unless there is a diode across the coil. If a diode is not present, you may attach positive voltage to either terminal of the coil and negative voltage to the other, otherwise you must connect positive to the side of the coil that the cathode side (side with stripe) of the diode is connected and negative to side of the coil that the anode side of the diode is connected.

[fsaviator]

Thanks, great info.  I appreciate you taking the time to lay it out.

I threw together a quick pcb with a couple 5v relays on it and it seems to work well.  I was using an old solenoid I had laying around.  The simworld switches arrived today so I plan to throw it together and see how it works.

I'll post some pics and such

[dc8flightdeck]

I look forward to your progress