Maximum output Power of V5's single port

Programming Support VEXcode V5 Tech Support
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I’m trying to discover the innovation use of V5-BRAIN. But I’ve been confused by some questions for a long time:

  1. What’s the maximum output power and rated output power of each port? Is there something like Power Limitation or Maximum Output Current Limitation for each port?
  2. Can I use just one single port to driver another passive module whose rated power is 30 Watts? What about 40 Watts? If the power is limited to less than 30 Watts, what can I do to solve my module driving problems? Using two ports or other solutions like this?

I learned that the output voltage is about 12~13 DCV, so I’ve added essential DC-DC transformer and other circuits to get the voltage I needed. The only thing I’m worrying about is the POWER limitation. Could u plz give me a hand and some ideas? Thanks a lot.

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According to this page, the maximum power draw of a V5 smart motor (which is the highest-power thing designed to be used with a smart port) is 11W. The ports might be able to provide a bit more than that as a safety margin, but 30W will likely be well above what a port can provide. But that’s just me guessing based on the motor specs, @jpearman can probably give you the real number.

What sort of “module” are you trying to drive? It might be a better idea for it to get its power from a separate battery.

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Well, 11W is the output of the motor, not input power.
The ports will supply 2.5A @ 12V (approx) to the motors, but they really are not intended to drive that much power for hours on end, and I certainly have never tested in that unusual use case.

I would add, when we do battery discharge testing, we use a resistive load on some of the smart ports rather than motors. The usual value for this is 8 ohm, so perhaps 1.5A current draw, that’s in the order of 20W (and even though these are really big 100W resistors they get very hot). I would try and keep any load you add at 20W or below.

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A post was split to a new topic: Battery not holding charge

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Thank u for replying. Oops, it seems hard to driver such a module whose rated power is more than 20 Watts continuously for several minutes. That’s so pity :cry: Maybe I should turn to another V5 battery, with which to drive my module separately. But, well, it leads to some other questions:

  1. Are the datasheets (or, some essential electricity features for circuit design) of V5 battery is public? If so, how can I get access to them?
  2. I found that if I don’t use the battery for a while, it will go asleep. How does this function work? (I guess there’s an output current detection chip. When the output current is zero or less than a tiny value, it orders the battery to sleep.) Are there some extra data exchange between battery and brain? And, will this sleep function affect my extra module?
  3. Emmm, what are the precise parameters or datasheets of the male&female connecting pin and where can I find these data? Or, what’s their official name and where can I buy them? You know, I have to design a circuit and it needs these data lol.

Could u plz give me some ideas on these problems? Thank u again for helping :grin:

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