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Additionally, each smartphone has to be plugged to a power source through a Plugwise Circle (https://www.plugwise.com/circle), so that the power source can be toggled on and off. The Plugwise Circles communicate with the Power Test Bench Server using the ZigBee wireless protocol. They must be installed within 3 meters of the Power Test Bench Server.
WIFI
The Power Test Bench Server dialogues with the devices with WIFI. WIFI stability is very important. See the WIFI Requirements
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