Serial communication problem in Provox

[Topaq_Khan]

Dear All ,

I'am using Provox system at a Polyester plant and faced following
clumsy problem some days ago . It is still unresolved

1- We drive variable speed motors with Siemens VSDs . These VSDs are
connected to Provox system via serial interface card 6921 ( USS
firmware ) and a RS232 to RS 485 converter . All drives are connected
in multidrop . Recently after a long stop plant was restarted . When
we found some of these drives turn off randomly . The drive good
signal on Provox DCD appears which triggers STOP 2 command to the
drive . Out of 28 drives some 6-8 show this behaviour randomly . We
checked all cables , grounding and converter . We even replaced the
serial cable and it's route . But problem persisted . Finally we took
off some 06 drives that were more frequent to problem from USS bus .
Then the chaos stopped . When we connect any one of these drive
again , this triggers a chain of tripping in otherwise normal drives .
We are certain that the drives are ok . Now we want to check the
serial interface 6921 but we dont have a USS firmware . CAN ANYBODY
HELP ME IN OBTAINING COPY OF BINARY FILE FOR THIS FIRMWARE SO THAT A
EPROM MAY BE PROGRAAMED AND REPLACED IN MODBUS FIRMWARE CARD TO MAKE
IT A USS FIRMWARE CARD ?

CAN ANYBODY SUGGEST SOMETHING BETTER TO MAKE ALL OUR DRIVES ONLINE
AGAIN ??

Nadeem Aziz

[Alosi, Tim [EPMR002/NEC]]

Hi,

The best way to access the firmware is via Emerson ... please call their
Global Support Center (you can find the appropriate number at
http://www2.emersonprocess.com/en-US/brands/sureservice/Pages/TechnicalS
upport.aspx )

Also ... I would think that in the time that passed between when the
plant was originally configured and now, that there are probably other
converters available for those drives.

I would suggest searching for a modbus interface for those drives and
use a standard Provox IDI ... newer hardware and more robust interface.

Sincerely

Timothy Alosi