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Technical questions (and answers?)

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Q What types of connectors are available to connect these components together? Each connector will be firmly attached to the side of a plastic box and will connect components from inside the box to components outside the box. We'd be using this as a passthrough to help make the tech water proof(ish.) The connector doesn't have to be water proof; it will simply help isolate the tech.

1. RasPi: 120V Power, 3 wires (standard computer power connector?)
2. Pumps: 12V power supply (the current connector might work just fine.) Perhaps connect to power and put power supply into the box? Simplifies wiring, but crowded in box?
3. 12 pumps: 2 wires each (24 wires at once? 3 sets of 4 pairs? 2 sets of 6 pairs?)
4. RFID pad to RasPi: 4 wires
5. Touchscreen: short ribbon cable (possibly keep in box, but no touch access)

Q: What gauge wire do we need to connect the pumps? They draw 380mA at peak. Plus an LED of some kind when the pump is powered.

Q: We'd like to add an LED to each pump so it goes on when the pump is powered. What resister do we use? (Yes, I know it depends on the LED. Let's just say a simple, standard red.)

Q: How many pumps can run from one power supply? The current power supply is 2A. Be nice to have 1 plug total for pumps. The startup can be guaranteed to be staggered = max = 11x280mA + 380mA (one pump startup.) All? Half? Alternately, is there a 12V power supply with enough current that we can use for all of them? (Is current the concern, or is it the voltage?)

Q: Curious: can the RFID reader pad be amplified?

Q: The RFID board needs protection since it will be outside the box. Dip this? Cover the components in some other way? Sandwich it in water proof foam?