Touch current and Surface devices

Touch current

Touch current may be detected when a device is plugged into wall (mains) power. Normally, electricity runs from the wall outlet, through the device, and back to the wall outlet in a short, closed-loop system. Touch current may be noticed if a tiny fraction of the electrical current passes through a user rather than returning to the wall outlet. Good device design and electrical safety hazard tests ensure that any touch current passing through a person is insignificant and non-hazardous.

There may be a way to reduce the touch current sensation perceived:

1. Unplug the charging connector from the Surface Connect port.

2. On the PSU, disconnect the figure-eight style connector at the end of the AC cord. Rotate the connector 180 degrees and then reconnect it to the PSU, ensuring the connection is secure.

   1. If your PSU connects directly to an outlet, unplug it, rotate the entire PSU 180 degrees, and then plug it back into the outlet.

3. Plug the charging connector back into the Surface Connect port.

Touch current does not occur when operating a device on battery power because the device’s power source (the battery) and its power system are contained completely inside the device. 

Safety and regulatory information

Microsoft’s internal standards for touch current, which are stricter than the applicable regulatory standards, are designed to minimize the perception for touch current.

To view the safety and regulatory information for Surface and Surface power supplies, including shipping information and AC power cord safety, see Product safety warnings and instructions.