Irfan, I copied your last post to this thread for further discussion:
http://www.mechmate.com/forums/showthread.php?t=60

If you see my outside connectors it has smps output, which has been taken out from smps and put on cb, it is connected from outside ups, there is no connector near smps fan. So my pc is also connected to ups. Since ups is big it can't be fitted in box :)

Nice going Irfan :)

As Irfan indicated that power goes frequently, although here is timebound power cuts, as a safety feature I added AC relay to input of contactor to control C11G EN switch. This now controls Estop when power is out and disables BOB as well.

I mention above wrong, DPDT AC relay controls Estop and 12 V spply to Estops from pc. i.e. long time ups power available. I tested it and it is working fine when power cuts.
I remember to read somewhere that power of bob should not be cut suddenly when pc is on. I donno for what reason.

HI Sharma, what's happening with your machine? any updates - I was expecting to see more work.

RGDS
IRfan

Nice machine, Sharma...

Looks like the world is slowly being painted blue...:)