Selecting the best paralleling gear for your business or customer’s business is a critical decision.  It is important to understand the variations of paralleling switchgear in the U.S. marketplace.  Over the years, paralleling switchgear has remained relatively the same.  A few traditional manufacturers use discrete subsystems and subassembly components. This includes Philadelphia Electrical Equipment Company’s Freedon iGear, Automatic Switch Company (ASCO) and Russelectric as an example. 

There is a second group of paralleling switchgear assemblers that have taken a different approach. They opted to integrate controls and devices into proprietary “black box” assemblies.  These companies include control switchgear supplied by some “Engine” manufacturers and some “Breaker” manufacturers.  These companies generally design and apply product with proprietary devices and PLC software programs that are not accessible to the customer, independent preventative maintenance personnel or service organizations and therefore the customer is held hostage by the suppliers restrictive design. 

There is a third group of manufacturers that have decided to follow non-traditional routes by breaking out the power switching components and going to devices such as IEC non-UL rated contactors for switching.  They move all generator controls, relaying and switchgear controls to small “black box” proprietary software systems.  This is similar to the second approach, however, they are cutting back on the power switching components, significantly reducing prices and not conforming to US standard NEMA and ANSI/IEEE practices and UL code requirements.  Most of these systems are not UL listed component systems and have the added disadvantage of being non-serviceable except by factory service organizations. 

The second and third approaches are proprietary.  They reduce their price by cutting down on discrete components, serviceability and independent reliability for the ultimate customer.  You are stuck.  The customer is tied to the availability and whims of one service group for service and parts replacement.  Further, these systems are limited in their application.  They have demonstrated peculiarities as related to a broad spectrum of power generation equipment and utilities that essentially prove to be non-viable in many applications.  The power control system should be independent of the power generation control.  It should allow both automatic and semi-automatic operation with manual backup schemes in the event of equipment failure.  No single source failure should decrease the reliability of the power system or remove the ability of the operator to run the system.  Whether the failure occurs at the multi-task PLCs, HMI touch screens, the critical paralleling switchgear must function safely.  A system supplied with a “black box” control, a “black box” monitor, proprietary protocols or software is not as reliable for the end user customer.  Multitask PLCs or PCs do not add to the reliability.  Synthesized PC or HMI screen displays are only adding “pizzazz” to the system and detract from the system performance and dependability.  These displays can not be calibrated and are not reliable.  They do not maintain the accuracy of purpose.  Digital display instruments or analog display instruments meet utility standards and are calibrated for accuracy.  Powering systems should allow for discrete control of engine generator set functions.  The design should allow for starting and stopping for active and reactive power control.  Systems that lack these features highly detract from the system reliability and performance.  This has been demonstrated in recent years by biasing regulation circuits and fuel control circuits in electronic engines.  These systems significantly detract from the performance of active and reactive power share and complicate troubleshooting and problem identification in the field.

Systems should interlace PLC functions with industry-proven control devices, by the Woodward and Basler companies.  This proven method offers the most reliable solution for control devices built for reactive power share. Woodward is the leader in the world market for engine control.  Basler is the leader in the world market for generator excitation control. These devices cost more and are commonly designed into PEECO’s Freedom iGear. 

What is a good paralleling switchgear package? 
A good paralleling switchgear package is one that is manufactured, factory-tested, and started up on-site, completely, and per any applicable specification.  The most reliable gear is the one with the most service options.  The gear should be capable of being maintained by factory personnel, the customer or independent service organizations.  A system lacking these capabilities is not beneficial to the customer and end user. In lesser cost paralleling systems you find items such as fuses, in lieu of reset able control circuit breakers.  Lesser systems use standard low end lamps in place of high quality LED indication lamps.  Lesser systems can lack DC/DC converters, UPS’s and multi-source power backups, suppressors, surge packages, AC breakers and DC breakers to protect the supply circuits.  Lesser systems offer only one mode of operation, not 3 modes of operation: fully automatic, semi-automatic and manual backup.  Lesser systems lack independent, duplicate monitors and the ability to access information on a real time basis.  Lesser systems cannot trend historical information with data logging.  These features are essential in a long term application of paralleling switchgear.  All these features make the PEECO Freedom iGear product slightly more expensive but highly more desirable.  The reliability, dependability and serviceability of the PEECO Freedom iGear prove to be a cost savings well into the future.

A major consideration in today’s marketplace is the new so called “expert” paralleling switchgear manufacturer.  They lack the decades of knowledge about past performance. Many new suppliers have come and gone with their “new ideas” due to the lack of knowledge.  These manufacturers assemble and install delicate digital/analog devices that are not suitable for harsh environments.  Putting delicate PLC, PC controls and digital instrumentation on engine generator sets in a high vibration and harsh environmental application will not survive over time.  In a standby, peaking paralleling or prime power system, there is no space for high-density plug and receptacle designs.  Large, unnumbered wire bundles may not be identified clearly.  Proprietary protocol systems, delicate and non-rugged fiber optic communication packages do not aid the ultimate customer.  None of these design philosophies add to reliability.

In conclusion, the customer, contractors and suppliers are best served with a paralleling switchgear system that is built to the standards of UL and NEMA plus ANSI/IEEE, NFPA including UL891, UL508 and NEC for the intended device application.  They benefit from paralleling switchgear that is built with independent products integrated into a single system.  The system should be designed for the power generation system or utility system.  It should be site specific, capable of being maintained by the factory, customer or independent service organization without the necessity of obtaining proprietary hardware or software from the original equipment manufacturer.  The system should be automatic with multiple modes of operation.  The system should have multiple display points to make it the most dependable system.