EL3040 ABB distributed control system industrial DCS module card

Description

Packaging details: if you need an urgent delivery order, please feel free to contact us, and we will do our best to meet your needs.

Price problem: if you find that other suppliers offer cheaper prices for the same product, we are also willing to provide you with reference prices and give you further discounts.

Phase unbalance protection U
Protection function U against phase unbalance is used in those situations requiring particularly
precise control over missing and/or unbalanced phase currents, only givin the pre-alarm signal. This function can be excluded.
Protection against overtemperature
The range of SACE PR122 trip units allows the presence of abnormal temperatures, which could
cause temporary or continuous malfunctions of the microprocessor, to be signalled to the user.
The user has the following signals or commands available:
– lighting up of the “Warning” LED when the temperature is higher than 70 °C (temperature at
which the microprocessor is still able to operate correctly)
– lighting up of the “Alarm” LED when the temperature is higher than 85 °C (temperature above
which the microprocessor can no longer guarantee correct operation) and, when decided
during the unit configuration stage, simultaneous opening of the circuit-breaker with indication of the trip directly on the display, as for the other protections.
Zone selectivity for protections S and G
Zone selectivity is one of the most advanced methods for making co-ordination of the protections: by using this protection philosophy, it is possible to reduce the trip times of the protection
closest to the fault in relation to the times foreseen by time selectivity, of which zone selectivity
is an evolution.
Zone 3 Zone 2 Zone 1
Zone selectivity is applicable to protection functions S and G,
even contemporarily and is available as standard on the PR122.
The word zone is used to refer to the part of an installation
between two circuit-breakers in series (see picture beside).
Protection is provided by connecting all of the zone selectivity outputs of the trip units belonging to the same zone together and taking this signal to the zone selectivity input of the
trip unit immediately to the supply side.
Each circuit-breaker that detects a fault communicates this to
the circuit-breaker on the supply side using a simple connection wire. Therefore the fault zone is the zone immediately to
the load side of the circuit-breaker that detects the fault, but
does not receive any communication from those on the load
side. This circuit-breaker opens without waiting for the set
time-delay.
ABB SACE provides important calculation tools to facilitate
the work of designers in coordinating protection devices, including the Slide rule kits, DOCWin and CAT software packages and updated coordination charts.
The zone selectivity function S and G can be activated or
deactivated using the keyboard.