The Scenario:
(20) 120VAC 5A and 10A devices. I would like to come up with a VERY CHEAP way to data log the power consumption of each device. I don't need exact power consumption with power factor correction or anything like that. I would gladly just deal with a reading of the amperage of each device and the assumed or measured voltage. I am more concerned about trends, not the real world kWH.
I have found current transducers that provide a mV output that can be fed to an ADC, but certainly can not see buying 20 of them @ $200 or more each.
I would like to use simple current transformers such as those shown in the following links: Both are Hall type sensors.
The problem (as I understand it) is that the output of these devices can not be fed straight into an OP-AMP for scalling and then to the ADC. Is there a different approach I should be looking at?
How exactly does one go about converting the AC signal from a current transformer into a DC signal usable by an ADC, and do it cheap enough to build 20 or more devices.
The plan is to use the Dallas 1-wire 4 channel ADCs (DS2450 i think) so that I can toss this right onto my 1-wire network.
I apologize if this is the wrong group.
Thanks in advance!