I'm using an adjustable desktop power supply (0-30 volt DC, 0-10 amp) to power my robot which has 7 standard 6-volt servos. There are some situations where the robot gets jammed, and power draw increases to 6A and recently I've even seen it hit 9.5A. I think my servo controller is only rated for around 5 amp continuous, and the servos are not intended to hit anywhere near that for any length of time. A servo burnout would be a big problem because I'd need to deconstruct, rebuild, and re-calibrate - none of which are easy operations.

So, is there any device that can set a maximum current and can be easily reset? I could use a traditional fuse, but may end up replacing those far too often. It's fine if the device affects voltage moderately, as I can easily adjust the power supply up a bit and honestly I'm happy if it lowers voltage when it needs to lower current as well - that would further help prevent damage.

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    $\begingroup$ I would caution you that servo datasheets will typically list a rated current at a particular voltage. If your servo is rated for something like 5-12 V, and it's rated for 5 A continuous at 6 V, then it's rated for ~(5*6) = ~30 W. If you bump the voltage up to 12 V, it will reduce your running current, BUT the 5 A now is delivering (5*12) = 60 W. If you're going to vary the supply voltage, be sure to check and re-fuse for the appropriate current! $\endgroup$
    – Chuck
    Commented Sep 4, 2018 at 14:11

1 Answer 1


use circuit breakers. That is the route I go. I really like the following: Allen Bradely 1492-ghXXX where XXX is the amp rating. Ex: a 4 amp fuse would be 1494-gh040, and a 10 amp 1494-gh100. they are slim profile, but are expensive as hell (as if sold by Lucifer himself - $120CAD!!!). Try to find cheap ones on Amazon or ebay. Another manufacturer, whose name does not come to mind also makes them. Another option is 'auto' circuit breakers:enter image description here

Just get a base and you resetting like a Boss! Those are all compact circuit breakers as that is what I prefer. You can also find non compact circuit breakers. There are tons of those.

All that is left is to decide if you will fuse every motor, or just the group. I would do the whole group... I won't bore you with electrical selectivity charts.



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