Skip to main content

I'm hoping that someone can explain as simply as possible for one not too well grounded (excuse the pun) in electronics how to hook up a set of MTH crossing gates to a relay switch and an insulated outside rail for operation. There are four color coded wires from each gate - red, black , yellow, and white (also a blue which I don't believe is employed). The relay switch I have is labeled: SRE 202D, 12VDC, 5A 240 VAC, 5A 28 VDC and has 7 pins. I have visited other discussions on this topic here but they leave me baffled. Any help would be appreciated. Thanks for reading. Mike
Original Post

Replies sorted oldest to newest

More information is needed:
Are the gates to be track powered or from a fixed voltage source?
What is going to be the power source ( 12 volts, DC) for the relay?
Do you know what the relay pinout is? ie: what the pins do?
Actually a 7 pin relay is rather unusual.
Normal connections are: Red is +
Black is -
White connects to normally closed contact
Yellow connects to normally open contact
Blue is contact common (Not track common)
Connections are from MTH website for # 30-11012 gates
I did this a couple of years ago. Hope it helps.
Black and Red are power to the gate. Note that Red is hooked to the center rail and Black to the outside rail for in this case a full 18 volts.

Touch the Blue and white together and the gate will go up or stay up. It will remain in the up position.

Touch the Blue and yellow together and the gate will go down and stay down. It will remain in the down postion.

My take on this but I could be wrong and by the diagram am:
Blue is Common
White is Normally Open (NO in the energize state)
Yellow is Normally Closed (NC in the energize state)

Your relay should have at least (5) pins My guess is that it has (8) (2) pins are for coil power. and there are (2) sets of NC/COM/NO contacts that you can use.

Pin (2) would be track power center rail
Pin (7) would be track power via the isolated rail section
Pin (8) COM would be the Blue wire
Pin (6) NO would be the White wire
Pin (5) NC would be the Yellow wire
If I'm wrong you would reverse White and Yellow wires.

SRE 202D, 12VDC, 5A 240 VAC, 5A 28 VDC and has 7 pins. This information indicates that the relay coil is designed for 12 volts DC, and that the NC/COM/NO contacts are rated for 5 amps 240 volts AC or 5amps 28 Volts DC. I'm not sure this relay will work. To energize the coil we would apply track voltage (AC) via the isolated rail section and Track power. My take is it should be an AC coil at or as close to the applied voltage as possible, most likely 12 or 24 volt AC
Finally had enough spare time and wired up with RadioShack parts as per the excellent diagrams above and now I have working gates tripped by an insulated rail (I still use O27 track and make my own insulated tracks with the help of double electrician tape pieces). Thanks to all above and to this website for always answering my questions. Mike
quote:
...(I still use O27 track and make my own insulated tracks with the help of double electrician tape pieces)...


I would recommend using friction tape or fish paper. If your insulated sections have seemed to lose their insulating feature at some point in the future, it is likely because the sharp edges of the tie stampings cut into electrical tape quite easily when the tabs are bent back down, and then the action of the trains causes it to happen over time.
Post

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×