Asked — Edited

Max Current Drain


I would like to control some relays with the digital out ports. What's the maximum current on those outputs ?

Best regards,


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#1 - contains specifications

25 mA

You can not power relays directly with the digital i/o. You will require a switching transistor. Or, you can purchase either an i2c relay device. Or a arduino relay shield. Both you can find on eBay:)


Thank DJ for your quick answer. I overlooked the pdf... way too enthousiastic to start off...:)
Yeah, to play it safe I was gonna use a transistor, though it would be easy to just hook a relay up to the board as I do with Arduino. Anyway congratz with this awesome product upon many of us have been waiting for.

Best regards, PG


Pg, thank you and you're welcome! Looking forward to your projects:D


Another Power Drain question: I know you said in previous posts to use a separate power source for the bigger servos (MG995) which I plan on for real use. However for testing purposes, wherein I will only be using 3 of those total and maybe 3 micro servos and a ping sensor. Could I get away with that on the board if that was all I was testing?


I've got 4 of the Mg995 and 2 of the HTX900 so far it's working. But when i do a lot of tricks one of the 2 transistors get warm.


Thank you Pabi!o. That's just what I needed to know. I will be using 3 of the Mg995 and 3 of the micros. It is only for testing so it seems it will work. But I will keep an eye ont he temp. Thanks!


If you have a 5+ amp/hour battery, you should be able to get away with a few of those heavy duty metal servos. Boy they are current hungry! I'll show you how many watts they consume later today. i'll post a pic

The VR's will get skin-burning-hot so watch out! Maybe add a fan to it, like someone did on here. It was a brilliant idea! A little fan from the computer store.