Limelight and Servo Hub on same Custom Circuit

Our machine is running out of PDP slots so we aim to drive our hood on the shooter with a Servo, leaving a slot left for a limelight. The servo in question would be the REV smart servo, which can pull a stall current of 2A.

Supposedly the Rio can supply 2.2A on the 6V rail, so alongside all other functions its getting close to the limit if the servo happens to stall. The alternative is to use a REV smart hub in a Custom Circuit with a limelight on the same PDP slot. This can supply the current required, but we aren’t sure if it’s legal.

The rulebook specifies that a custom curcuit cannot drive a actuator specified in G501, that being motors and servos. Our question is if the REV Servo Hub is driving the servo, does the servo not count for being part of this circuit? It seems like this rule is in place to stop people running 10 servos in parallel on the same PDP slot.

Alternatively, will a single Smart Servo cause problems when powered from the RIO?

See R505 regarding what servos are allowed to be connected to. Is the “REV smart hub” you’re referring to the “REV Robotics Servo Hub (P/N REV-11-1855)”? If so, it’s legal to connect the servo to it.

I agree there seems to be a potential gap in the rules as to how the Servo Hub is actually categorized in the power distribution side of things–it would seem to be a CUSTOM CIRCUIT as it falls into none of the other categories, so doing a split power feed with a Limelight would seem to be legal (note you have to wire them into a splice, not just stick two sets of wires into the PDP), but it might be good to clarify with a Q&A.

That being said, if the Rio is specified to provide up to 2.2A, and the max the servo can draw is 2A, you should be fine powering it from the Rio if you just have a single servo.


Nevermind, the Servo Hub was removed from R505 in Team Update 1, so it is not legal to use.

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Just realsied I may have given you some wrong info. We plan to use the Rev Servo Power Module, not the servo hub. It seems like that’s all good to use, and probably better than a discontinued product anyway.

Not a discontinued product. It’s a delayed release product. Should be announced later, but not available for this season.


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