Greetings! I'm putting together a way to monitor our office power, specifically when it switches to a backup generator, and when the backup generator performs it's monthly self-test. I'm going to monitor and log all of this on a computer (and eventually page me if there is a problem).
Essentially, I'm going to use three power adapters from discarded equipment (each will output 8-12 VDC) and plug them into each power circuit I'm going to monitor - one on the local electric company side, one on the generator side, and one on the load side. Then the output from the adapters will be connected to a serial input on a computer running a VB6 application that polls the serial port. I've worked out how I can monitor three distinct inputs using a single serial port, and the essence of the VB6 app that needs to read inputs from the serial port. My question relates to checking if there is any concern using power adapters providing signals directly to a computer serial port. I am planning to put single-socket surge protectors on each adapter to hopefully protect against reasonable surges. The monitoring computer is going to be about 30 feet away from the outlets it will be monitoring.
In addition to the surge protectors, should I put some kind of isolation ckt between the outlets and the circuitry providing inputs to the computer? (An OpAmp, maybe?) The output voltages of the power adapters (8-12VDC) are perfectly acceptable and within the range of a serial port. I know in the extreme case of lightning strikes, all bets are off, but are there any recommendations for protecting a computer when taking inputs connected to power outlets?
Thanks in advance!
Ken
Essentially, I'm going to use three power adapters from discarded equipment (each will output 8-12 VDC) and plug them into each power circuit I'm going to monitor - one on the local electric company side, one on the generator side, and one on the load side. Then the output from the adapters will be connected to a serial input on a computer running a VB6 application that polls the serial port. I've worked out how I can monitor three distinct inputs using a single serial port, and the essence of the VB6 app that needs to read inputs from the serial port. My question relates to checking if there is any concern using power adapters providing signals directly to a computer serial port. I am planning to put single-socket surge protectors on each adapter to hopefully protect against reasonable surges. The monitoring computer is going to be about 30 feet away from the outlets it will be monitoring.
In addition to the surge protectors, should I put some kind of isolation ckt between the outlets and the circuitry providing inputs to the computer? (An OpAmp, maybe?) The output voltages of the power adapters (8-12VDC) are perfectly acceptable and within the range of a serial port. I know in the extreme case of lightning strikes, all bets are off, but are there any recommendations for protecting a computer when taking inputs connected to power outlets?
Thanks in advance!
Ken