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How to restart my computer after power cut?

  1. May 9, 2012 #1

    my computer is running 24h with a software which controls an electric equipement.
    This software is working as a PLC, so when i start this software i have to specify the date, time and the number of cycle which it must start.

    during a power cut, my computer is running in UPS for 2 hours but after it shuts-down.

    What i want is:
    during a power cut, a small program in java or c must detect a state of a relay which will shuts-down my software and my computer properly and when the power cut come back, my computer should restart and the small program must start my software depending the date and time.

    Is it possible?
    I heard about the ADAM6060 module which can be used to detect the state of a contact from a relay.

    Does anyone have a clue ?

    Thank you
  2. jcsd
  3. May 9, 2012 #2
    First of all what PLC are you using?

    Also, what software are you using to communicate with the PLC? What you are talking about is running some sort of start up script that automatically takes the current date and time and stores it in the program.
    Some PLC's allow you to set the date and time directly via a 'freeport' command which would eliminate the need to do this via the program so I will need to know the details of how you are communicating to the PLC. Creating a start up script to reload the host program shouldn't be an issue.

    Finally does the ups have either a relay or transistor output that changes state on loss of supply? You will need this to initiate the shutting down of the software and PC again a simple script should do the job nicely.

    Last edited: May 9, 2012
  4. May 9, 2012 #3


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    I think he means that the computer ACTS as a PLC in his setup (i.e. it is controlling equipment using a DAQ of some sort).

    The kind of software you are describing is sometimes included with the UPS. What kind of UPS are you using?
  5. May 9, 2012 #4
    on newer computers thier is usually on option in the bios for this.
  6. May 9, 2012 #5


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    Afair, Apple have done this for a long time.
  7. May 9, 2012 #6
    Do you have any voltage or current sensors?, can you rewire them to any backup low cost PLC?.
  8. May 9, 2012 #7
    In fact, there is no PLC but our house made software acts like a PLC and controls an electric equipment like heating resistors, cooling resistors, measuring pressure, flow etc...and in the same it sends emails automatically to me every hours about the state of each sensors... and i will include the power cut/on message in the message.

    The UPS we are using have a relay contact. (brand chloride Linear plus 10KVA)
    Maybe it's more complicated that i imagined.
    I hope it's clear now.

    Thank you all
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