siemens card 505-7012 disfunction


Thread Starter

majush philip

i got a siemens 505-7012 analog card 8in/4out in one of our machine.for last few days i am having some problem with it.when i am starting the machine after a long break the card functions well after 5 minutes the output from one channel ceases. i have also noticed that the card is getting heated. i have done a cold check for all the components but found ok. can any body help me in repairing it.
What is happening to the current on the channel that goes out?
have you tried another card?
IS the voltage OK?

If you have card extender, put it on the extender, and heat the card up with a small heat gun, since it is dying when getting hot. I would not cool it down, of course if it works when it gets cool, then you know that the problem is related to a part getting hot. have you felt the compnents to see if you can determine which one is over heating? if you don't a card schematic, replace the card and troubleshoot it on the bench, if the problem persists after replacing the card, check the loop you're driving, something is failing, drawing too much current or has a bad termination, causing a high resistance and the card is attempting to drive it.