Upgrade of ABB legacy drives

iconsys received an enquiry from a long-established Aluminium rolling company for an upgrade to one of six Roller Table tracks in its hot rolling mill.

The original equipment had been designed and manufactured by iconsys in 2002/2003 and comprised a suite of fully-regenerative ABB ACS600 drives. The ACS 600 range became Legacy products in 2004, and the Client recognised that the future cost and availability of spares etc. could be a threat to the hot mill’s continuity of production.

The objective was to upgrade the Roller Table Drive System from Legacy Drives to Current Drives during the one-week annual Maintenance shutdown in August 2018, with the system fully operational and ready to go into production at the end of this period.

Our Solution

The solution proposed by iconsys was to remove the obsolete ACS600 equipment and replace it with ABB’s current ACS880 products of equivalent rating, retrofitting the new equipment into the original suite of enclosures, which would remain in position throughout the operation.

iconsys Engineers first carried out a Site Survey in order to identify any possible difficulties and establish the best way to proceed. The ACS880 range being considerably more compact than the ACS600, it was decided that the new Line Filter and IGBT Supply Unit (ISU) would fit comfortably into the space vacated by the original Line Filter alone, leaving the original ISU bay empty.

However, the ACS880 installation practice, whereby wheeled modules are rolled into place by means of a detachable ramp, meant that a section of the original front-mounted 30x10mm Earth Bar would have to be diverted to the back of the enclosure to pass behind the ISU and Filter. A new section of busbar would therefore have to be accurately made in advance ready to be fitted on site.

Similarly the DC busbars supplying the four inverters would have to be extended through the former ISU bay (now empty) and connect to the new ISU DC fuses. These busbars were all manufactured in iconsys’ workshops prior to the commencement of the site work.

The existing Incomer, main Contactor and Precharge hardware were all found to be in good condition and were retained in the interests of economy.

The new equipment includes a BLCL-13-5 line filter, an ACS880-204-0580A-03 ISU and four ACS880-104-0140A-3 Inverters, which are controlled via ProfiBus. A copy of the original PLC control software was modified offline by an iconsys Engineer to adapt it to the new generation of Drives.

Following the removal of the old equipment and the installation of the new hardware and software, the iconsys Commissioning Engineer commissioned the complete system and subsequently returned to site to provide standby support when production resumed the following week.

Results

• Replacement of obsolete machinery
• Improved reliability
• Increased production
• Improved user friendly