Thanks Richard, looks like I'm off to the hobby store! I'll let you know how it goes.

Make sure you buy a lipo that can delivery a minimum of 25C... If it has heavy duty battery leads then it is the one you want....

I've said this before many times. I don't think it's a good idea to channel power for servos on these big robots through the EZB. Using the EZB as a power conduit will only rob the EZB of voltage when the servos start sucking current. Yes I know Voltage and current are two different things but it's a fact of nature that one depends on the other. On these bigger servos that are moving heavy loads you should route your power around the EZB. A alternate power supply is even a better idea but I've found this really unnecessary unless your PS is underrated for your amp load. By simply running power directly from the PS to the servo (or it's properly sized step down regulator) you will avoid EZB brown outs.

Also throw out the in line linear voltage regulators and get some Switching BEC's.

Castle Creations CC Bec 10A 6S Switching Regulator

Good Luck.

@richard thanks I'm here now. Just in time!

@dave I originally for my testing purposes had this set up with separate power going to these servos. This is the first time I have the system set up all thru the EZB. Since the d ports are longer regulated, I let the EZB power to be the same as the big servos at 7.4v then I have bec's on the 2 micro servos for the eyes. The jaw servo gets its regulated power from the audio servo control board. I think the length and gauge of wires might be my a problem too. Worst case I'll just set up the big servos on their own direct power from my line in and avoid putting that thru the EZB. I find it hard to believe with all the digital ports and the EZ servos rated higher than standard servos (6v I think) that mine would brown out with just two servos?!?

My EZB browned out with only one 7.4v HS-7950th servo attached. It's tested to pull 4.8 amps in a stall/lock on situation. It was also mounted inside a servo City gear box (see below) and lifting about 3 lbs at the end of a 12 inch channel (the B9 claw and wrist sold by a B9 club vendor. You know how heavy that set up is). When I rerouted the power directly to the PS I had no issues. Wire size is very important and perhaps larger wire would help to allow current to pass to and from the EZB easier. However my theory of routing power through the EZB is when the current reaches it, it still has to pass through several connectors, another fuse, pins and board traces that are smaller then your enlarged wire before it exits and moves on the motor. Sounds like a bottle neck to me.

Here's the one servo mounted in the gearbox that browned out my EZB under load:

Electricity is very strange and will do strange things. My experience as a power distribution lineman who has been working on and repairing low voltage and overloading problems on a large urban power grid for almost 35 years now show me that overloaded wire can handle a lot of current. The voltage will drop some but usually it will heat up or melt. Under constant load the loading device will just keep pulling the current is needs till the conductor fails. More powerful devices like DC motors will rob current away from more sensitive devices like electronics if they are on the same circuit. In situations where there are low voltage problems on our power grid our engineers usually have us install larger transformers closer to the load. However sometimes we'll also upgrade the wire sizes if they are obviously to small.

Now startup load is a whole norther animal. This is probably what is causing the EZB brown outs. When the servo starts up the current demand spikes. If your feeding servo through the EZB the PS cant deliver enough current quick enough to keep the it up and running. This happens on our urban power grid also. When big industrial customers start turning on their motors and other current hungry devices the voltage on our distribution lines start to drop. We place large capacitors in line that switch on at times we know this will be a problem (like in the morning of a work day) to keep the voltage from sagging. We don't usually change the conductor size (unless it's a huge current draw like a fire pump), we just add ampacity. Our little servo, sensor and EZB circuits are much the same as a big city power grid, just smaller.

Sorry if I bored anyone. I thought this may be useful to this issue.

@Dave, not boring at all. That actually helps a lot in explaining this situation.

Particularly the bit about the high draw devices "robbing" from the low draw devices.

Alan

Excellent info Dave. I just tried a larger gauge wire and seems to be working better, but now I think just for safely purposes I'm gonna reroute power to the large big bad boys. You right there are lots of bottle necks along the way as I have to be able to dismantle the pieces so there are connectors here and there, lots of servo pins for the lack of a better word. It should not add too much more wiring to the already tight neck and head. I'll let you know how it goes.

Thanks again and NEVER boring!

Hey guys ,popping in for a moment, I was going to wait till next week , but I will drop the bomb now. Obviously I have been a supporter of "external power for high torque servos" for obvious reasons. I will soon have a version of my inline regulators that use external power , a ground reference and a signal pass through. This way there is still adjustable voltage but from a external source.

Castle BEC are great , but the cost is also very high as well, that being said mine are value focused for the budget minded hobbiest, student or child.