If this is the wrong place , sorry it seemed the most appropriate. and i am out of my depth with most things electronic, though i am slowly picking things up.
my issue is that i am using a set of scales with a usb interface via a usb host shield. And i may need to power off and on the scales half way through a 4-6 hour process controlled by the arduino.
when the scales are connected to a usb master (arduino shield) they draw power over the usb so a relay on the scales psu wont reset them.
can i break into the usb connecting cable and fit a normally closed relay inline on the +5v line to effect a hard reset? or would this screw the comms up (causing dificulty in restablishing them, change of device id or some such)?
the scenario is a nano brewery where at the start of the brew the ambient temperature will be low however during the initial stages heat will be generated as a byproduct of heating up a large(ish) volume of water.
starting the scales in the cold and warming them up over a few hours may effect the load cells? and the readings they generate. As the scales dont come into play until at least an hour or so into the process im thinking only turn them on when needed and when the ambient temperature has normalsed around room temp (16-20C)
As automating the process is a lot to do with not having to switch leads plugs and hoses about all day
i would rather not plug in the scales just before need and would much prefer a single intitial power on for all aspects of the system..
thanks in advance for any and all input.