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Low voltage piezo switch, light controller.

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pattherat

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I am building a couple of underwater lights activated by a piezo switch. The light will consist of a lead acid 12v 2.4ah battery running 3 - 220 lumen LEDs. I have the LED circuit already working. The switch needs 10 - 24v ac/dc, .4mA max. to hold the switch on or off. Max current through the switch for the LED circuit is 150mA. I plan on using a relay in here somewhere but I need to reduce current coming from the battery so I don't over power the switch. I am not super knowledgable on electronics so I need some direction. Thanks.
 
When you say the switch is: "10 - 24v ac/dc, .4mA max" - what will happen if you put the switch directly across the 12v supply?
 
I'm not sure what would happen and since it's a $40 switch I'm alittle unwilling to try something that I'm not sure of the outcome.
 
The switch is from Barantec and the specs can be found here. **broken link removed** There is a data sheet and a drawing.
 
The data sheet says the switch will conduct .5 amps to the LEDs without a relay. I don't see where you found the .4 ma limit.
 
Looks like I may have added a "." in front of the 4mA by accident.
The switch that I purchased is the SBA1TAAW1N.
The label on the switch is as follows, I realize it doesn't quite match the datasheet.

Blue 10-24v ad/dc 4mA Max (these two lines are bracketed)
Blue 10-24v

Yellow Output 10-24v ac/dc (these two lines are bracketed)
Yellow Output

Continous load current 150mA
 
That's why I always go back to basics and never believe anything the customer says.
The figures provided at the start did not make any sense.
Simply connect the AC/DC wires to the battery - in either direction or if a red wire is provided, connect this wire to the positive terminal of the battery and the other wire to negative.
Connect the output of the sensor, possibly yellow, to one of the coil terminals on a 3amp relay and connect the other coil terminal to the negative of your battery. The 3 amp relay will be a 12v type with a coil resistance of at least 120 ohms.
When you push the button, the relay will click and when you push it again the relay will release. Make sure you get this type of switch.
Now connect the output terminals of the relay to the LEDs, by connecting one terminal to the negative of the battery and the other terminal to the black wire of your LEDs. The red wire goes to the positive of your battery.
 
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When things get this fishy, I recommend contacting the manufacturer. They are, after all, responsible for providing readable, unambiguous specifications. I tend to put their feet to the fire when they go all "maybe" on me.
 
The relay will not be the problem. Put a LED and 470R resistor (in series) across the relay coil.
 
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Tried this, did have any affect. The relay is a solid state job. I tried the circuit with a coil/mechanical relay and it works great. Now I need to find a relay is alot smaller.
 
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