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This is from the icreate 2's document: "Pins 1 and 2 (Vpwr) are connected to the Roomba battery through a 200 mA PTC resettable fuse. The continuous draw from these two pins together should not exceed 200 mA. Do not draw more than 500 mA peak from these pins, or the fuse will reset." My project just need to draw a bit more than that number. So is there anyway to disable - short circuit - that fuse or replace that fuse with a bigger one? where does that fuse reside on the bot's circuit board? If the above 2 is not possible (because the fuse is embedded inside some chip or too difficult to access for example), is it safe to run a small wire from the battery pole to the pin to by pass that fuse?

  • I know I can run a wire directly from battery pole to my circuit or draw power from the motor wires, but I love running through the serial port with keep things simple.
David
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    Have you looked for the fuse, yet? On electronics, fuses are often as close to the connector they are protecting as possible, and are marked with a reference designator beginning with "F." Just be careful -- fuses are often there for a solid engineering reason, and if you short a fuse, there's no telling what else might blow up, instead. – Steve Dec 15 '15 at 17:36
  • Thanks for the tips, Steve. I looked and found not one but four fuses next around the port! It must be one of them, though I can't trace the multiple layer circuit board. I got to run a pair of wires from the battery poles and add connector to it for now. Still hoping someone might "happen" to know the circuit so I can get rid of these wires and connector – David Dec 23 '15 at 19:14
  • I agree -- it is very difficult to trace circuits with low circuit impedance, like a fuse. From experience, Here are some ways to find them when you're hacking electronics (these tips relate to many products).
    1. Look to see if the you can visibly trace copper from the fuse to the port of interest.
    2. If you're looking for a PTC resettable fuse & you have a thermal camera, short the output and see what gets hot!
    3. If you've found fuses but aren't sure if you've got the right one, carefully remove it from the circuit board and see if your very low impedance becomes a very (very) high one.
     – Steve Dec 23 '15 at 19:17

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