Think of it like the water system in your house. When you open the faucet the city water system (or your well pump) doesn't determine how much water flows out. They provide a constant pressure (voltage), and depending on how much you open the tap (load), either more or less water flows (current).
Other than making sure the pump (power supply) can provide the maximum flow (current) you'll ever need, you don't worry about the size of it when you change the load from watering your plants to filling your swimming pool.
The circuit will draw what it needs.
The formula for calculating this is A=V/R where A is amps, V is volts and R is the resistance of the load in ohms.
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Then what you want is a constant current power supply. This is a device that will regulate the current by varying the voltage. This normally requires an active stage on the output to achieve this, You can also current limit the output by putting a resistor in series with the output. A 0.8 ohm 250W resistor on the output will limit the current to 15A even if you short the wires. It will dissipate a lot of power in the resistor though. Google "constant current source" and you'll find lots of info.
The 16.5 amps is maximum output - if you want to limit the output you use a thing called a circuit breaker or you design what is attached to not pull more than 15 amps - it is not like it is going to push false amps through your circuit.
You need to study electricity more.
just add a current limiter to the circuit. My website shows how you can do this. You WILL need to use components that can handle over 15A.
VERY SIMPLE, JUST ADD A CONSTANT CURRENT STAGE AND SET IT INTO 15A AT THE OUTPUT SHALL DO.
i can use it at 16.5 amps but just to be safe i need to lower the amps. i can break it oped, but what component controls the amps and how can i adjust it? i can solder and im pretty good at modifying electronics, i just never understood power supplies because i dont work with them much
