We are a urea manufacturing complex and have installed Hima H51 system for our ESD. From last few days we are facing a problem that suddenly all the output cards go to fails safe and cause total plant shutdown.

The error codes being displayed on CPU show all input cards failure. But on checking there is nothing other than these codes which can lead us to problem. We have common 24 volt power supply to input card racks and CPU rack. The CPU rack has further got a 5V supply whose input is same 24V supply. But the thing is the CPU rack doesn't get affected with this problem. We changed the 24V power supply bank but the problem is still persisting.

If anybody can share his experience with HIMA or in general, do reply and ask in case of further specific detail. It would be good if someone can tell me about its building blocks as well which can help to identify problem.

 

Ussama, this is your SAFETY system. WHY are you asking us??? You should have immediately contacted HIMA who have lots of highly trained engineers, troubleshooters and FSEs to help you.

I would NEVER ask for advice from anybody but the vendor on a ESD that has experienced such a widespread failure.

Please, contact HIMA now. Before something damages your plant and causes injury or death.

Walt Boyes
Editor in Chief
Control and Controlglobal.com
www.controlglobal.com

Mailto:[email protected]
Read my blog SoundOFF!! At www.controlglobal.com/soundoff

 

I thought there might be anyone who is a regular visitor here and knows about it. We did contact HIMA but haven't sorted out the issue exactly yet. Thats why i was just thinking of any help from anywhere.

 

Ussama,
Please check the 5VDC Power Supply in your System. Because a Power Dip in the 5VDC Supply can halt the CPU and disturb the Logic of I/O Cards.

Moreover, Try to seperate the 24VDC Power Supply of CPU from I/O Cards (if the same Power Supply is being used for the CPUs and the I/O Cards).

The, List Down any changes that you might have observed during the time of Failure, before and after as well.

Another Problem can be with the Grounding of your System. Make sure that the System is properly grounded and there is no Floating Voltage on 5VDC or 24VDC Power Supply with respect to COMMON GROUND.

Out of the Blue, you can also check the Power Supply Cards for variation in Outputs. Any Sort of Ripples or Disturbances on Load (or without Load) can be causes of Failure as well.

I hope this of Help for you.
Feel free to contact in future.

Best Regards,
Rehan Asif,
Pakistan.

 

>Rehan,
Thank u so very much for ur kind and sincere suggestions. One of my very tallented colleagues has come up with an idea of having R&D on power supplies of our system n hopefully will b coming up with some results shortly. I will keep u posted with the progress in troubleshooting.

By the way u seem to have done a lot of work with hima.....if i m not wrong u are the project lead for HIMA in ASIA.
Plz remain in contact as this would be helpful for us.

Regards,
Ussama

 

Ussama,

Hima provides free of cost support to all its customers by email and phone. Mr. Samran from FFC is already in contact with HIMA for this matter. As per correspondence from him he has replaced a power supply and the issue has not recurred. There are several possibilities for failures and these needs to be investigated in detail. I cannot think of any good reason to expect that FFC can receive better support from anyone other than the OEM.

Rehan Ahmad
Hima Middle East