Power supplies

Lynxmotion Electronics & Software
1

Hello,

For SSC 32 board, is it possible to connect 6 VDC power supply to VS1 (for nano servos, 0-15 channels) and another one 7,5 VDC to VS2 (for stronger servos, 16-31 channels)?
How much current intensity can be deliver to servos through this board ?
Many thanks in advance for your answers.
Zag6872

2

Hi Zag,

Here are answers to your questions & comments:

Yes that is totally possible! The dual input for power on the SSC-32/SSC-32U is meant for two main uses:

  1. Provide more total current to servos by having two power supplies (VS1 for channels 0-15 and VS2 for channels 16-31).
  2. Provide a different voltage to each row of channels (VS1 and VS2 would have different voltage levels).

Of course, if you do use two different power supply (one at VS1, one at VS2), please do remove the two VS1=VS2 jumpers before connecting your power supplies. Not doing so will most likely kill the weakest of the two supplies.

If using the SSC-32, please note that you should also remove the VS=VL jumper (if present) and provide a separate power source for your VL to prevent brownout. Typically people have used a 9 V DC battery but you can probably get away with a simply 6 V DC wall wart, too (or a 2S LiPo battery pack @ 7.4 V DC).

If using the SSC-32U, you do not need a power source on VL (actually not recommended) since the VL is internally powered by VS1 through a circuit on the board. It also has some beefy capacitors to prevent brownouts (a common problem with the older SSC-32 if no proper VL was provided). Again, do not place a VS=VL jumper (off by default).

From a quick back of the hand calculation, the SSC-32 & SSC-32U should both be able to supply ~3 A continuous on each row of channels and more in peak. In practice, we’ve used peek currents well above 5 A with no issues. That being said, we did not really test its limits but the entire board has been used with 4 DoF hexapods and humanoids with 24 servos with only one power supply on VS1 and no visible issue with run times of 10+ minutes.

Therefore, it should be able to pass quite a bit. It should be noted the power goes directly from the screw terminals of VS1/VS2 to the traces and then to the output pins (VCC/GND) and therefore has little resistance on the way. If you do end up having a board that seems to be heating up abnormally you may want to consider using a 2nd board to control your remaining servomotors.

We hope this helps!

Sincerely,

3

Many thanks for all these informations.
Sincerely
Zag6872