The etc-12 Q Series trip unit is a suitable retrofit replacement for the Schneider Electric / Merlin Gerin Masterpact M ACB range STR28D, STR38S, STR58U and STR68U trip units fitted on Masterpact breakers.
Unlike the original STR‘s the new satinAMERICAN etc-12 Q Series trip unit can be used on different frame sizes (3 or 4 pole) and is able to be rated to suit any Masterpact breaker as it does not require a rating plug. This means that it can also then be moved and used on another breaker if required. In addition it is also compatible with neutral sensors in residual ground fault protection schemes.
Once installed on a Masterpact (or equivalent Moeller XZM/Square D branded unit) air circuit breaker, the etc-12 Q Series trip unit is secondary injection tested with an ETC Technologies test set across each phase individually as well as ground fault if fitted; proving the protection. When installed the etc-12 Q Series can be programmed with exactly the same settings as the replaced faulty STR, with the additional benefit of being programmable via the front panel control buttons and including an LCD display to view both settings and trip events. The display can also give a “live” view showing current per phase for monitoring and pick up indication.