Electrical Relays - HELP!!!!!
Discussion
Thanks Guys.
The online catalogue doesn't carry anything like what I'm after.
I've also tried the 2 relays in the circuit but unfortunately only 1 will ever seem to trigger. Can't understand it as my school boy physics logic says that both should. One of my relays appears to have a little diode in which must be allow some current through allowing the other relay to trip, but not the other.
Confused!
Mark
Anyone any other ideas???
The online catalogue doesn't carry anything like what I'm after.
I've also tried the 2 relays in the circuit but unfortunately only 1 will ever seem to trigger. Can't understand it as my school boy physics logic says that both should. One of my relays appears to have a little diode in which must be allow some current through allowing the other relay to trip, but not the other.
Confused!
Mark
Anyone any other ideas???
Guys,
Thanks for all your advice. Please bear with me as I am still learning a lot about auto electics.
Yes it is a 12v system, yes I do need to have 2 INDEPENDANT circuits switched either by 1 relay or 2.
I have tried 2 relays (they both work ok independantly)but wont work together when linked in series in the same circuit. Which is why I was thinking about the feasability of a 'double switch' relay.
To expalin matters more it is for a Nitrous kit bottle heater circuit.
The circuit comes live when a switch is thrown in the car. The switch also illuminates. There is also an automatic pressure switch in the switch circuit so when the heater gets the gas to the correct pressure the pressure switch cuts the current and switches the relay for the blanket off.
This is ok so far but the problem is I'm in the cockpit with the heater switch on and still illuminated so I don't know if the gas is at pressure. (can't butcher the dash for a gauge).
I though the simple solution was for the pressure switch circuit to trip the heater relay AND another relay taking the eath from the switch light.
I though Bingo! Switch on illuminated = heating not at pressure......... Switch on, light goes out = pressure achieved, heat off light off, therefore GO!
There must be a simple way of achieving this, but so far this numpty is still rolling a square wheel!
Mark
Thanks for all your advice. Please bear with me as I am still learning a lot about auto electics.
Yes it is a 12v system, yes I do need to have 2 INDEPENDANT circuits switched either by 1 relay or 2.
I have tried 2 relays (they both work ok independantly)but wont work together when linked in series in the same circuit. Which is why I was thinking about the feasability of a 'double switch' relay.
To expalin matters more it is for a Nitrous kit bottle heater circuit.
The circuit comes live when a switch is thrown in the car. The switch also illuminates. There is also an automatic pressure switch in the switch circuit so when the heater gets the gas to the correct pressure the pressure switch cuts the current and switches the relay for the blanket off.
This is ok so far but the problem is I'm in the cockpit with the heater switch on and still illuminated so I don't know if the gas is at pressure. (can't butcher the dash for a gauge).
I though the simple solution was for the pressure switch circuit to trip the heater relay AND another relay taking the eath from the switch light.
I though Bingo! Switch on illuminated = heating not at pressure......... Switch on, light goes out = pressure achieved, heat off light off, therefore GO!
There must be a simple way of achieving this, but so far this numpty is still rolling a square wheel!
Mark
I feel I'm getting closer to my Nirvana! 
ok a circuit in words (if possible).
3 amp feed to illuminated switch, out to pressure switch, out to relay (which would switch 25Amp heater circuit on/off depending on pressure switch position) and out to earth. This circuit works ok so far.
Illuminated switch has an earth. Bulb stays lit whether the heater relay is on or off. My thought was to put another relay in the bulb earth circuit to also be triggered by the the on/off current from the pressure switch.
For some reason when doing the additional relay to the first circuit only 1 of the relays will fire, usually the one on the bulb circuit? This confused no end.
My simple thought was therefore to get 1 double pole relay to be triggered by the pressure switch and then activate the higher amp heater circuit, and the low amp bulb earth.
There must be a simpler way of achieving this.
One thing I have thought of is that the 2 relays I was trying with were both 30amp, but from different manufacturers. One definately has a diode in and is usually the relay that wont throw when in a twin situation. Would this be an issue?
Thanks again
Mark
ok a circuit in words (if possible).
3 amp feed to illuminated switch, out to pressure switch, out to relay (which would switch 25Amp heater circuit on/off depending on pressure switch position) and out to earth. This circuit works ok so far.
Illuminated switch has an earth. Bulb stays lit whether the heater relay is on or off. My thought was to put another relay in the bulb earth circuit to also be triggered by the the on/off current from the pressure switch.
For some reason when doing the additional relay to the first circuit only 1 of the relays will fire, usually the one on the bulb circuit? This confused no end.
My simple thought was therefore to get 1 double pole relay to be triggered by the pressure switch and then activate the higher amp heater circuit, and the low amp bulb earth.
There must be a simpler way of achieving this.
One thing I have thought of is that the 2 relays I was trying with were both 30amp, but from different manufacturers. One definately has a diode in and is usually the relay that wont throw when in a twin situation. Would this be an issue?
Thanks again
Mark
Right think I've got it!
1 way would be to put the pressure switch in the circuit first. Pressure on = all circuit off, including the bulb. Only down side is total dead circuit I would not know if pressure ok, or one of many fuses has gone. Will dwell on this
Other way would be to put switch first, then pressure switch then relay for the heater, then to ground. I could interupt the 25Amp heater circuit after the first relay, and install the second. I could actually use the higher amp circuit to switch the lowere amp bulb earth.
One thought (reference the circuit live or not scenario) would be to put a 2 position relay for the bulb earth. For example, while heater on, relay switches bulb relay to earth for 'red' not ready setting,...
... then when the pressure switch activatesoff it triggers the heater relay which switches the red bulb from earth and back through a green bulb (ie for 'go').
This (I hope) when the main arming switch is on a red bulb for heating, and green for correct pressure and heat off. If switch on but no bulbs then I know I have a fault.
Phew.
What do you think???
Thanks again
Mark
1 way would be to put the pressure switch in the circuit first. Pressure on = all circuit off, including the bulb. Only down side is total dead circuit I would not know if pressure ok, or one of many fuses has gone. Will dwell on this
Other way would be to put switch first, then pressure switch then relay for the heater, then to ground. I could interupt the 25Amp heater circuit after the first relay, and install the second. I could actually use the higher amp circuit to switch the lowere amp bulb earth.
One thought (reference the circuit live or not scenario) would be to put a 2 position relay for the bulb earth. For example, while heater on, relay switches bulb relay to earth for 'red' not ready setting,...
... then when the pressure switch activatesoff it triggers the heater relay which switches the red bulb from earth and back through a green bulb (ie for 'go').
This (I hope) when the main arming switch is on a red bulb for heating, and green for correct pressure and heat off. If switch on but no bulbs then I know I have a fault.
Phew.
What do you think???
Thanks again
Mark
wedg1e said:
This any help?
Wedg1e,
Thanks mate. Will be giving it a go. The right hand 'heat' lamp looks as though it will only come on when the heat is on, I need it to go off, or illuminate in the off position.
Think I will fit a switching relay and have the bulb (green) to come on when the relay switches away from the heat. This will give me confirmation that the circuit is working (illuminated) but heat is off/pressure correct as relay switches over to the bulb.
Confusng but I think I understand it.
Thanks all for your help.
Mark
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