Look Inside the Breaker Cabinet

Apr 11, 2022 | substations, breakers, Utilities
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WHAT ARE THE VITAL SIGNS UTILITIES ARE MONITORING ON A TYPICAL GAS INSULATED CIRCUIT BREAKER?

With 8 sensor inputs, 5 timing inputs, and an onboard ambient temperature sensor and supply voltage monitor, the Optimizer3 Circuit Breaker Monitor and its array of sensors deliver a complete diagnostics report of a circuit breaker’s performance. Click on each breaker cabinet component to see how.

 

CURRENT TRANSFORMER CURRENT TAPS

Current Transformer Pickup Coils enable the Optimizer3 to measure real-time current flow in the bushing current transformer secondaries. The arc duration time is measured via the bushing current transformer’s current taps. The main interrupter contact wear is monitored, based upon the fault current and arc duration.

AC/DC VOLTAGE SUPPLY

The AC or DC voltage supply is continuously monitored by the Optimier3 via AC or DC Voltage Transducers. This provides a health status of the power supply to the breaker’s critical mechanisms, including the heaters, air compressors, winding motor, etc. Upper and lower voltage limits can be set to activate an alarm.

BREAKER TIMING

When the breaker trips, the Optimizer3 measures several important breaker travel timing parameters via a direct hardwire connection to the breaker’s 52a and 52b switches. Breaker trip coil timing is a key indicator of a breaker’s overall state-of-health.

TRIP & CLOSE COILS

The Optimizer3 measures trip and close latch time via a direct hardwire connection to the trip and close coils. The idle condition of the trip and close coils, the time it takes the trip latch to operate, and the time it takes to operate the closing latch are all monitored.

SPRING WINDING MOTOR

The current draw and run time of the spring winding motor are monitored using AC or DC Current Transducers. When the breaker’s trip coil pulls the trip latch, an enormous amount of energy stored in the spring is released, opening the breaker in a matter of milliseconds. After the breaker closes, the spring winding motor runs for a short time to compress the spring. The Optimizer3 will be able to detect if there is a problem with the motor or the winding mechanism by monitoring the current drawn while running.

CABINET HEATERS

Continuously-running cabinet heaters keep the inside of the control cabinet warmer than the outside air, preventing moisture from condensing on vital equipment. As these heaters run continuously on AC current, they are monitored using an AC Current Transducer. The Optimizer is programmed to issue an alarm if there is a drop in current, indicating the heater may be about to fail.

SF6 GAS PRESSURE, DENSITY, & DEW POINT

SF6 gas density, temperature, and pressure are monitored using Density or Pressure Sensors to ensure its insulating properties are sustained. From these measurements, the Optimzer3 calculates the mass of the gas and can determine if there is a leak while also calculating the leak rate to forecast how long before a low gas alarm will be initiated. The moisture content of SF6 gas can be also monitored using a Dew Point Sensor. These sensors record SF6 gas use and simplify annual EPA reporting.

GET THE PRODUCTS

Click through each system component for additional details and ordering information. 

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