The LCL is a behemoth floating crane that lifted huge pieces of bridge into place of the new eastern span Bay Bridge in San Francisco, CA. The LCL crane was designed by American Bridge and built in Shanghai, China by ZPMC in 2007. It floats on a huge barge and is pushed into place by tug boats. The floating crane can then manipulate itself to the exact position by using 8 anchor winches on the corners of the barge. Once in position, the four spuds (piles) are lowered into the bay mud to hold it in position. The LCL has a maximum lifting capacity of 1750 tons or 3.5 million pounds.
Epic Engineering, LLC of San Rafael, CA is the control systems integrator responsible for all the automation and controls aboard the floating crane. Epic has been servicing the LCL since 2008.
There are 18 AC variable speed drives/motors that move the boom, main hoist, anchor winches, and others. A multitude of operating stations and sensors all feed back into the main computer (PLC) and logic determines allowed moves. Three 550KW diesel generators are onboard to supply the necessary power.
The HMI (human machine interface) displays the current status of all the motors, generators, and sensors. The HMI allows the operator to control which generators needs to be on depending on the required load. Any faults or alarms will be displayed and logged.
The originally supplied HMI's (2) were two panel PC's running Windows XP. The PC's had standard hard drives and cooling fans. Over the years while operating on the salty bay air, the intake cooling fans started to rust and erode. Also, the end of support for Windows XPspelled the demise for these panel PC's.
Epic Engineering determined that a hardware and software upgrade was prudent. The old system was a master slave configuration. So if the master PC went down, so did the slave PC. The new configuration is two independent HMI's. A fan-less panel PC running Windows 7 PRO and a 64GB solid state drive. These "no moving parts" PC's will last much longer in the salty air. Of course when upgrading to Windows 7 the application software needs to be upgraded too. This gave us a chance to upgrade the firmware on all the GE PLC cards. The GE Machine Edition was upgraded from version 5.5 to 8.5 and Cimplicity7.0 to 8.2. The new panel PC's had dual network cards. One was used for the main PLC connection and the other was used to connect to 4G LTE modem that enabled us to VPN into the PC.
The HMI retrofit was completed and the customer now has an up to date and faster system that will last much longer. Plus, Epic now has the ability to monitor and troubleshoot the PLC system from offsite which can save the customer thousands of dollars in travel costs.
Joe Hiti – President - Epic Engineering, LLC