Retrofit or Replace Circuit Breaker? Masterpact trip unit replacement
the etc-12 Q-Series Direct Replacement Trip Unit for the Masterpact M & MP Breaker
Masterpact trip unit replacement solution: For our customers who may be replacing or retrofitting a Masterpact Breaker because of problems with power breaker current tripping, Satin American offers a replacement for Masterpact circuit breakers. First, a little background on why Satin has engineered the etc-12 Direct Replacement Trip Unit Masterpace breakers.
VINTAGE “AIR BREAKERS” — THE EARLY YEARS
Low-voltage air power circuit breakers were designed in the late 1930′s. For the past seventy-five years, and even today, they have been used in virtually every industrial application. Between the 1930′s and 1960′s, these breakers utilized series overload devices to sense current and provide time delays. While the series overload is a robust and reliable design, it has several limitations. Specifically, overloads do not offer the precision and selectivity available with modern electronics, and certain protective functions, such as ground fault, are simply not available.
Despite these limitations, some new breaker designs used overloads into the 1980′s. Around this time, numerous failures began to manifest due to the fact that many of the existing overloads were reaching the end of their useful life. The cost of replacing or retrofitting a breaker was increasingly becming a concern. Some of the biggest problems involved oil leaking from dashpots, and oil changing viscosity, affecting the time delay feature of the dashpots.
FAILED POWER BREAKERS AND SWITCHGEAR CAUSE DOWNTIME
Because the old power breakers were well made and expected to have a long service life, they were frequently employed in critical applications that require continuous operation. Replacing a failed overload or older generation solid-state trip unit is often problematic because most OEMs no longer provide support for these systems. Commonly, OEMs recommend replacing the old breakers with the current production model. Not only is this approach expensive, it often requires significant downtime as switchgear needs to be replaced along with the power breakers.
The basic design of low-voltage “air” power circuit breakers was developed in the late 1930’s. For the past seventy five years, and even today, breakers of this design have been used in virtually every industrial application. Between the 1930’s and late 1960’s the breakers utilized series overload devices to sense current and provide time delays. However, while the series overload is a robust and reliable trip unit design, it has several limitations. Specifically, overloads do not offer the precision and selectivity available in modern electronic designs and certain protective functions. For instance, ground fault protection is simply not available with overloads.
Despite concerns, however, some new breakers utilized series overload devices up until the 1980’s. Around this time, numerous failures began to manifest due to the fact that many electromechanical overloads were simply reaching the end of their useful lifespan.
To address this issue Satin American introduced its product line of etc-11 retrofits in 1988. Today, these kits are available for any United States manufactured power circuit breaker and can be installed by individuals skilled in basic circuit breaker maintenance. In a just a few hours a breaker can be removed from service, retrofit, upgraded, tested and returned to service.VINTAGE SOLID STATE RETROFIT COMPONENTS
* An Electronic Trip Unit which can be considered the “brains” of the system. The trip unit receives an input from the current sensors and decides if it should start timing for a trip based on this information. Electronic Trip units are generally self-powered meaning that they obtain the power required to run themselves from the circuit being monitored. Original electronic trip units usually had a system of flags, targets or flip-dots that indicated which band a breaker tripped out on.
* Current Transformers (CT’s) which are doughnut-shaped devices encircle the current path. These CT’s provide a current output that is proportional to the current flowing through the bus. Current Transformers are rated with a primary and secondary current value. For example a common ratio of a CT is 1600 / 0.2 A, which means that when the primary (bus) current is 1600A, the secondary current is 0.2A.
* Bus Details are often required to re-direct current flow in 1600A frame and below breakers. This is because the original current path was through the series overload device that is removed as part of the retrofit.
* Flux-Trip Actuator is a electromechanical device that converts an electronic trip impulse from the Electronic Trip Unit to mechanical energy which ultimately opens the breaker.
etc-12 Masterpact M & MP Breaker Replacement
Although a vast majority of breakers have been retrofit in the late 1980’s and 1990’s, Satin American’s etc-12 proves the solid state retrofit is more relevant today. It improves upon features of the original solid state trip units, providing new features that help maintain an electrically safe workplace and greatly reduces the dangers associated with an arc-flash event.
The etc-12 address end-of-life issues by providing an easier solution for upgrading breakers still equipped with overloads or first generation electronic trip units approaching the end of useful life.
Learn more about the etc-12 Q-Series Direct Replacement Trip Unit for the Masterpact M & MP Breaker: http://www.etc-12.com/
Speak with a Sales Engineer: 877-706-7767