Customers regularly ask similar questions. To make it easy to get answers below are the initial entries for the new FAQ.
Testing was done using an Arduino Uno R3, Servo Shield 2, Hobby Wing 8A UBEC, Turnigy 4500mAh 2C Li-Po, 8 Hextronik HXT 900 servos, 6 Hextronik HX5010 servos and 2 RobotBase RB-421 servos. Measurements were preformed with an Agilent U1272A.
1. The servo power pins short on the USB connector
As with some other shields the Servo Shield 2's servo header pins touches the USB connector on some Arduino and compatible hosts. There are two ways to solve this, firstly use an additional set of headers between the shield and the host or, my preferred way, place a bit of electrical tape over the USB connector. Using the tape solves the problem for the Servo Shield 2 and many other shields.
2. How much current can the Servo Shield 2 carry?
Different online trace width calculators return slightly different results. According to the trace width calculator on CircuitCalculator.com it can carry up to approximately 2.25A (Track width is 36mil, 35um copper thickness, 2.25A requires 36.2 mil).
However real world testing has shown a peak of 7A with continues draw of approximately 4A (More than 10 minutes of continually moving of all 16 servos), with no noticeable temperature rise in the Servo Shield 2.
3. How to supply more current to the servos
The easiest way to allow for more current is to solder jumpers between the servo power and ground pins.