I just got one of these Arduino sensor shields so I can hook up some servos. There isn't much documentation on this shield, but from what I read if you remove the pin connector next to the power input, you can power it externally. Also from what I read, you shouldn't power it with more then 5v or you can damage the arduino underneath.
So the question is, how can I power this thing if I hook up 10 servos to it? I connected a 5v 1A power supply to it, and it works with one servo alright, but with 2 or more the servo's get jittery. I'm assuming it needs more amps, but I don't know how much this shield can handle. Anyone get a bunch of servo's working with this thing and an external power supply?
Connect the power supply in Parallel with the board, but don't run the power Thru the board. Only the control signals and Gnd needs to connect to the board.
If you want all the servos to move together, budget 1A per servo. If you sequence them you can
get away with less as the current typically peaks on motion (unless you are physically
overloading them, in which case they will probably overheat anyway). You'll have to look at the
thickness and width of the power traces on that PCB. You may be able to solder tinned copper
wire on the back across the ground (G) and power (V) pins of all the 3-pin connectors to bolster the
current handling - easy if they are all lined up.
Pull that jumper and confirm the 5V pin on the power header is not connected to the 5V going to the servos.
If it is, and you plan to power the Arduino from the same 5V, add a diode from (anode) to Vin (cathode) to prevent reverse driving the regulator too much. 1N4001 type will do.
Ok, so if I pull the pin off and piggyback the shield on top of the arduino, the ground would be connected, so I could use 2 separate power sources (USB for Arduino, and something like a 5v/8amp power supply for the shield).
I believe the SG90's stall current is 650 ±80mA, so 10 servos would need about 7.3amp, so an 8-10amp power supply would work.
