relay on a power inverter

**gtz** · 08-16-2006, 04:17 PM

ive purchaced a reed relay from radioshack.. part # 275-233 spst - 12vdc rated 0.5a at 125vac.. i have it soldered to the switch on the inverter and the switch is set to off... then i apply the 12v ignition source to the relay , the inverter powers up just fine.. and everything operates.. however once the ignition is shut off the inverter continues to run.. the relay is normally open btw... i have to unplug the relay from the inverter then when i plug it back in the inverter remains off until the key is turned back on.. once again the inverter comes on fine but will not shut back off.... am i using the wrong type of relay??
the inverter switch reads 11.7 v when the inverter is off and 0v while the inverter is running..

here is the pin out

Coil
|
Com ------------------/ --------- N.O.
|
Coil

i have the 12vdc+ to the top ciol and the ground to the bottom coil..

the 12v+ from the inverter to the common and the 12v- from the inverter to the N.O. can anyone see why the relay is not opening back up after the ignition source is shut off?

**Wiredwrx** · 08-16-2006, 05:39 PM

Originally Posted by gtz

ive purchaced a reed relay from radioshack.. part # 275-233 spst - 12vdc rated 0.5a at 125vac.. i have it soldered to the switch on the inverter and the switch is set to off... then i apply the 12v ignition source to the relay , the inverter powers up just fine.. and everything operates.. however once the ignition is shut off the inverter continues to run.. the relay is normally open btw... i have to unplug the relay from the inverter then when i plug it back in the inverter remains off until the key is turned back on.. once again the inverter comes on fine but will not shut back off.... am i using the wrong type of relay??
the inverter switch reads 11.7 v when the inverter is off and 0v while the inverter is running..

here is the pin out

Coil
|
Com ------------------/ --------- N.O.
|
Coil

i have the 12vdc+ to the top ciol and the ground to the bottom coil..

the 12v+ from the inverter to the common and the 12v- from the inverter to the N.O. can anyone see why the relay is not opening back up after the ignition source is shut off?

Your wiring is screwey.

What do you mean that you have +12 to comm, and -12 to N.O. The common and the NO get connected when the coil is energized. Why would you want to connect the - and + 12 volts. How the thing works at all amazes me. Something just doesn't seem right.

Please revise/confirm your wiring description.

If it is by chance connected correctly, check to see that the accessory wire is actually dropping to zero volts when the ignition is turned off. Some cars can keep an accessory wire "hot" for a period of time after the car is shut off.

Michael

Michael

**gtz** · 08-16-2006, 05:52 PM

ok.....

:|

here you have the inverter switch

ON OFF
_________
| |
_________

Wire 1 Wire 2

12v+
(the inverter supplies (the inverter draws 12v from this wire)
this wire with 12V+)

so...... if you hook a voltmeter up red to wire 1 and black to wire 2 you get 12v... actually 11.7.. so.. the wiring IS CORRECT when the inverter kicks on the switch drops to 0V .. why?? i dont know.. but this is how the inverter functions right out of the factory box..

now i purchased the said relay from my first post and connected wire 1 to the common lead on the relay and wire 2 to the N.O lead on the relay
the coil lead (on the top ) of the diagram has 12v from my ignition source.. and the bottom coil lead is sent to a ground...

ok i hooked everything up except the 12 ignition wire.. and turned the key on.. i touch it to the 12v remote lead from my amps.. and the inverter powers on like its suspose to .. however it will not powere off.. (remote wire completly unhooked.. ) unless i disconnect the relay then it dies.. inother wards the relay is getting stuck colses until the inverter is disconnected from it.. when i reconnect the relay it stays open until i touch the remote wire agin.... then it powers on.. and sticks closed...

the relay works fine.. (ive tested continuitity and applied power and it opens and closes properly.. until i hook it back up to the inverter.. and it sticks.. and i cant figure out why.. i went just now and purchased a big 30 amp auto relay and am going to try it.. its too big and ugly for what i had in mind.. but ill post back if it fixes the problem mabey the other relay is just tooo small.

**Wiredwrx** · 08-16-2006, 05:54 PM

Try the diagram in "Paint", and then post it. The board messes with ASCII drawings.

Michael

**gtz** · 08-16-2006, 05:55 PM

these forums mess with the homeade diagrams.. trust me i am positive its wired correctly.. i just am trying to find out why the relay wont control it.. i dont want to use the big relay unless i have to because the small relay i currently am trying(and having probles with) is wired up inside a project box along with multiple other circuts wo keep them all nice and neat looking.. and i have it running out of the project through 15 pin dsub connectors to ensure i can easily remove and install things as needed.. that wait if a relay goes out i can just disconnect the box and change / add things inside without haveing to mess with all the wiring..

**Wiredwrx** · 08-16-2006, 05:59 PM

Originally Posted by gtz

these forums mess with the homeade diagrams.. trust me i am positive its wired correctly.. i just am trying to find out why the relay wont control it.. i dont want to use the big relay unless i have to because the small relay i currently am trying(and having probles with) is wired up inside a project box along with multiple other circuts wo keep them all nice and neat looking.. and i have it running out of the project through 15 pin dsub connectors to ensure i can easily remove and install things as needed.. that wait if a relay goes out i can just disconnect the box and change / add things inside without haveing to mess with all the wiring..

Try paint or describe it better. I have no idea what wire 1 and wire 2 are, and what black and red wires are, which is ground, which is accessory, which is positive, which is for the invertor switch, which is the inverter wires or wire colors.

Be as specific as you can. You seem to think it is wired correctly, and it may be. If it is wired correctly, it doesn't make any sense, unless you are putting to much power through the relay, and fusing it, but I would believe if it was fusing, it would never return to normal. That is why I believe you have it connected incorrectly, but with out knowing the wiring diagram, that is impossible to say.

Michael

**gtz** · 08-16-2006, 06:22 PM

ok i got it.. i had to use the big auto relay.. i guess the other relay was just too small.. i managed to cram the big relay into the box.. altho it leaves me with no room for futur upgrades..

i am prewiring everything up in the car.. and all the relays/ fuses/ resistors .ect into a box that is loacted inside the computer in the trunk.. on the back of the computer is a 15 pin dsub connector which runs inside the project box hidden inside the pc case.. this way i can remove the pc and EVERYTHING functions stock.. but thwn i hook the pc back up my relays take control of the amps.. inverter and caps... however if i unplug the dsub connector everyhting will fucntion as if there is no mods done to any of it. this is all so i can incorporate a usb relay controller or anything else in the furute and the hook ups are already there.. i just have pl;ug in the new box and will not have to mess with the wiring i have already installed into the car..

thank you for your help tho.... just so everyone knows...

the 0.5a 125v relay couldnt handle the inverter and was sticking closed.. i used the 30 amp auto relay and it works fine.... BUY THE #) AMP RELAY NEXT TIME

**Wiredwrx** · 08-16-2006, 06:54 PM

Glad to hear you got it worked out.

Your idea sounds cool and interesting, but do keep in mind a couple of things, though from the description you provided, it is hard to tell if this is relevant,

A D-sub connector CAN NOT handle anywhere near 10 amps of current through it. Please do not attempt to feed to much power through the D-Sub. There are heavy duty quick disconnects that you can use, and might be appropriate to mic those with the D-Sub.

Also, make sure you fuse the wires going from the battry to your box/trunk.

Michael