A \u201chigh availability\u201d system comprises multiple switches under the control of multiple control processors. Data received from a first tier of low-power input source is used to determine userenvironmental context and activate a second tier of input source that operate in a higher power range. There is no need for specialized needles and other paraphernalia related to an IV, and no specialized training is needed to install and operate the device. On the basis of this request, the PC sends the interest data corresponding to the login user. The reduced weld crack susceptibility enhances the repair weldability, including when planishing is required.