Legacy RTU Upgrade


Design Features 

The key to the vast savings in time and money lies in our upgrade approach that allows you to leave the local I/O terminations and original field I/O wiring in place. If any of the I/O interfaces are active PCB modules that are unreliable or not adaptable to an NTX series interface, we may be able to replace the original vendor’s I/O terminations with form and fit blank termination boards that have the same terminal block layout. Or, we can strategically locate our standard Analog or Binary input modules so that relocating the original termination wiring requires minimal effort. This still results in a significant savings in installation and test labor (even if the original wiring has to be moved to the replacement termination boards), as well as long–term maintenance cost savings for these sites. In all cases, the original legacy control relays can be reused, if they are still considered reliable.


With NTX series RTUs, you can configure the RTU master communications database, through Virtual RTUTM addressing, to duplicate the legacy RTU database in its original protocol envelope. This solution lets you:


  • greatly reduce wiring and test labor, and engineering costs associated with RTU replacement
  • eliminate substation wiring drawing revisions and master station database and display revisions
  • eliminate the most failure–prone or unsupported electronics with extremely reliable and fully–supported NTX series hardware and software
  • reduce the time required to modernize existing installations from weeks to hours
  • obtain many more years of useful life from existing equipment and installations
  • take advantage of the latest RTU technology, such as modern open protocols; high–capacity, high–speed master and slave gateways (serial and/or TCP/IP); modern Windows® PC–based configuration and diagnostic tools
  • take advantage of modern communications digital interface mediums
  • segregate vast amounts of data into separate Virtual RTU addresses; supply this data and control capabilities to multiple master stations at no additional cost
  • integrate IEDs inside and outside the existing substations


Other Upgrades

 ACS has successfully developed and deployed 2nd Source RTU upgrades for more than 25 different hardware models.  Solutions available include upgrades for the following units:


–BBC/CSI 7000 series

–CDC/EMPROS/Siemens 8890

–Ferranti Outpost

–Harris 5000/5500

–ILEX 8200

–L&G/Moore Systems MPS-9000/MPS-9000S

–L&G Telegyr 5300/5500 

–L&G Telegyr 5310/5520

–L&G Telegyr 5700

–L&N Conitel C300

–L&N Conitel C2020

–QEI 4050/4151

–SNW SR-8000, Type 1 and 2 

–SNW SR-8500 and SR-8550 

–SNW IR-8600

–Tejas CAM/DAC 

–Westronics M3 & M4/Harris 6000

–Westronics/Harris/GE D20/D200 and peripheral I/O panels 


If you don’t see your particular model listed here, give us a call.  Chances are we can come up with a solution for yours as well – saving you thousands of dollars and delivering the most advanced, reliable substation controller technology available today.  After all, with more than 18,000 remote terminal units delivered over our 36-year history, few vendors know the business like we do.


More Information

For more information call 800.831.7223 or contact This email address is being protected from spambots. You need JavaScript enabled to view it.




ACS Legacy RTU upgrade solutions Brochure PDF

ACS Legacy RTU upgrade solutions Brochure

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Gateways and RTUs