auto invert input bits

Dear experts,

i am diagnosing s5 system ,two racks are used in this system with use of 115U CPU 944,

Both rack are connected with use of IM 306 <=>IM 306, Dgital input 32xDC 24 v available with second rack,

My problem is that Di status changes automatic without physical input change,i have replace  di module with other one but problem remain same, i cant find where is problem,

Please explain if any idea.....

thanks in advance

Hello,

You can try to disconnect connector from board and see what happens.

Maybe problem is in cable or in connector.

Best Regards

Do you have any error from IM306 ?

Sometimes a damaged cable or plug of ET200 bus system brings similar Problems.

Is it an IM306 or IM306C ?

this problem not with all inputs, but at least 50%, problem not remain constant but some time for moment only ( physical inputs  and logical inputs Different,)

Hello,

for my good understanding of your problem

1) some inputs with logical "1" is changing to logical "0" ?

2) some inputs with logical "0" is changing to logical "1" ?

3) both states in point 1 + point 2 ?

When your answer is point 3, so is possible an error with 24V PSU or somewhere in connecting cable system is short circuit between 24V and GND

Jenda

Hello,

for my good understanding of your problem

1) some inputs with logical "1" is changing to logical "0" ?

2) some inputs with logical "0" is changing to logical "1" ?

3) both states in point 1 + point 2 ?

When your answer is point 3, so is possible an error with 24V PSU or somewhere in connecting cable system is short circuit between 24V and GND

 thanks Mr.jenda for reply

3) both states in point 1 + point 2   is occurred at here, i have check power supply its ok, becouse same power supply for first rack there is no any problem with first rack,

I do not know how you designed the inputs and outputs to physical sensors and valves, but try to disconnect successively to each input card with 32xDI all inputs.

I have encountered the same problem => the cause was a metal s*** between 24V and GND somewhere in the machine and machine vibration caused problems mentioned

ANKURGAMIT

 

Jenda

Hello,

for my good understanding of your problem

1) some inputs with logical "1" is changing to logical "0" ?

2) some inputs with logical "0" is changing to logical "1" ?

3) both states in point 1 + point 2 ?

When your answer is point 3, so is possible an error with 24V PSU or somewhere in connecting cable system is short circuit between 24V and GND

 thanks Mr.jenda for reply

3) both states in point 1 + point 2   is occurred at here, i have check power supply its ok, becouse same power supply for first rack there is no any problem with first rack,

Thank you very much

Mr.mindware
Mr.IBN-Service
Mr.Jenda

finally i have replace one by one component  and diagnose ,there is no any problem occurred after replacing im 306,