Basler Electric BE1-51 K1E Z1S B1C6F / BE151K1EZ1SB1C6F Time Overcurrent Relay

DESCRIPTION

BE1-87T Transformer Differential Relays provide primary protection for power

transformers and are available in either Single-Phase or Three-Phase

configurations. The solid-state BE1-87T compares the currents entering and

leaving the protected transformer. If a fault is detected, the relay initiates a trip

signal to isolate the power transformer. This limits damage to the transformer

and minimizes the impact on the power system.

BE1-87T relays use three types of restraint:

• Percentage of through-current

• Second harmonic

• Fifth harmonic

Selectivity in differential relaying is based on the ability to distinguish between

internal and external faults.

This is achieved by comparing the currents into and out of a power transformer.

Comparing these currents often requires more than two inputs.

For example:

• Power transformers may have a significant portion (greater than 10 %) of the

current flowing in a third or tertiary winding.

• Power transformers can have multiple breakers for a given winding (e.g., ring

bus or breaker and-a-half bus).

BE1-87T relays are available with up to five restraint inputs for the single-phase

unit and up to three restraint inputs per phase for the three-phase unit.

The SR8A Retrofit Voltage Regulator is an economical, direct replacement

for existing Basler Electric SR8A voltage regulators. Designed for brush

and brushless synchronous generators, it delivers precise voltage regulation,

fast response times, and dependable excitation control while fitting within

the same mounting footprint as the original SR regulator.

The retrofit package incorporates a modern AVC125-10 voltage regulator and,

where required, an internal sensing module, simplifying installation and

minimizing downtime.

Engineered for reliability in demanding power generation applications, the

SR8A Retrofit supports single- or three-phase sensing, voltage matching,

reactive droop compensation, line drop compensation, and underfrequency

protection. Its rugged design withstands harsh industrial environments,

while compatibility with accessories such as excitation limiters, power factor

controllers, and auto synchronizers makes it a versatile solution for generator

upgrades and modernization projects.

The SR and SSR Retrofit Voltage Regulators are designed as economical,

direct replacement solutions for legacy Basler SR and SSR voltage regulators.

Engineered for quick installation, these retrofit kits fit into the existing

mounting space and utilize terminal-to-terminal wiring to simplify field

replacement. Integrated CT input burden matching supports paralleling

systems with cross-current compensation, while accessory inputs provide

compatibility with var/power factor controllers and excitation limiters.

The SR and SSR Retrofit series delivers the same dependable performance

as the original regulators while helping extend the life and reliability of

generator excitation systems.

The FGD-2 Field Ground Detector Module is a transducer that continuously

monitors the resistance of the field circuit of a synchronous machine with

respect to ground. It applies a fixed voltage with respect to ground which

causes a small leakage current to flow. The FGD-2 provides a low voltage

output signal proportional to the leakage current.

The voltage output is measured by a compatible product and used for field

ground protection.

Two versions of the FGD-2 are available. A low-voltage version, rated for

800 Vdc maximum generator field voltage, is provided for brush or brushless

exciter systems. A high-voltage version, rated for 1.750 Vdc generator field

voltage, is provided for static exciter systems.

The metal enclosure of the FGD-2 offers electric shock protection from

incidental contact. A compatible footprint and identical functionality make

for simple replacement of a Field Ground Detector (FGD) with the FGD-2.