No Response To Gws Servo

Well that victory was short lived. Although the connections were not touched overnight now this morning when I powered up I got nothing, in fact the EZ board now shuts down completely (blue light goes ), and doesn't just break the signal like before. The gears on the servo turn freely by hand so it isn't locked. I suppose the motor is somehow shorted inside and that in turn shuts down the board (I've tried it with 2 boards). I'm totally stumped. This is the second servo that I've tried for this function. I'm thinking this may not be the best approach for what I need.

Thanks to everyone for their help.

Daniel

@mulberry.

Sorry to hear that. Maybe the board in the servo go damaged through all the testing with various connections and insufficient power supply being pumped through it, or your still facing power issues. There not much else I can suggest other than what's already been mentioned, or look at using a different make of servos. If the EZ Robot ones don't meet your requirements, Hitec servos are pretty good and work well with the EZ -B, and they have lots of different voltage and torque choices available. May be something to think about.

What are you using to power the servo? If it was burned, it would smell really bad.... I still think it's still a power problem... The servo needs a Lipo or niMh battery.... Your bench supply or D cell battery won't work....

As Steve suggests... there is only 2 reason why the servo isn't working... Not enough power or it is defective...

Can you just use one of the ez robot servos in it's place? They are pretty much one of the strongest servos I have seen for their size?...

No smell and the unit doesn't get warm when it's powered. The shutdown of the EZ concerns me. Since it works freely with standard EZ servos I'll assume the HD servo was damaged with the testing (lesson learned) .

Next step will be a new servo (It's got to be along the configuration of this one to fit my bracket) and try a stand alone battery recommendation (like a LiPo). I do have a couple of 12 volt rechargable HiTec batteries but that would require a voltage converter to bring it down. I wanted to avoid batteries if possible since my robot is stationary and most of my build is 12 volts (from a wall outlet) distributed with a block to converters for a few components that require less power but I'm letting that approach go.

Oddly enough I though the electronics of this build would be far simpler than the physical construction which took 3 years. Its looking like animation will take as long.

Daniel

@mulberry.

Testing with a new servo and LiPo really is your best bet. Going back to the "amps" issue, that's something you would also have to consider IF you decide to use a voltage regulator to reduce and match the servos voltage requirements. Good luck and keeps informed on your progress.

I just don't understand how you guys can feel that testing with a battery is the best way to go. Could you please explain this to me? I'm not being a smart a** here but just trying to understand your advice. Maybe I've been missing something but don't you have to match the battery to your devices amp draw plus some overhead room just like you would do for a power supply? If he has a properly sized ps why mess with a battery that will be draining down while you trouble shoot and configure? Seems simple, find the max amps the motor will pull when stalled and get a quality power supply that will supply more amps than you need. We're not talking about the common wall wart here. Again, what am I missing?

@Dave Schulpius,

Search the forum for "inrush current" and specifically read anything posted by @jeramie.

In short, the issue is that when first starting to move, servos draw way more amperage than they are otherwise rated for. Most power supplies limit to 5 amps, and you need more like 15 or 20 when the servos first start.

There are power supplies that will work, and in fact jeramie recommends one in one of the posts that talk about this, but they aren't cheap.

Alkaline batteries also can't deliver the amps, but NiMH and LiPo can.

Alan

Just to echo what Alan said about LiPo's and nimh's being able to supply the amps needed to deal with the start up power inrush, and the fact that standard batteries (alkaline) and many transformers cannot. Also to refer back to what I mentioned earlier about using a tried and tested method many people use successfully in the aim to narrow the issue down further. Not to say alkaline batteries can't be used, but you would need to put a multiple battery packs in parallel to get enough current , but that could end up being a lot of batteries. Thats how I understand it anyway.