Circuit Breaker Analyser

Do you know the true condition of your Circuit Breaker?

It is critical that the circuit breaker and protection relay operate correctly during faults. The CBTrip can measure how the circuit breaker would perform in a real fault situation by capturing the vital first trip.

With the addition of Total Trip Time the CBTrip can also provide the composite trip time of your protection relay and circuit breaker.

From this simple online test, a slow trip operation can be detected and the problems rectified to ensure in future there is NO:

  • Widespread losses of supply
  • Damage to plant
  • Safety incidents
  • CI / CML financial penalties

The CBTrip offers a cost effective solution by providing:

  • Capture vital first-trip operation
  • Total Trip Time  (Relay + circuit breaker)
  • Onsite analysis of breaker defects
  • Trending of key parameters
  • Efficiently target critical resources
  • Minimize outage times

CBTrip with Replay Pro provide powerful diagnostic tools for analysing:

  • Main contact operation
  • Auxiliary contact operation
  • Trip and close coil operation
  • Integrity of control circuit wiring
  • DC supply voltage
  • Relay operating time (using Total Trip Time  function)
  • And many more potential defects

What is Replay Pro?

  • PC based software package that can be linked to a central server so that data can be made accessible company wide
  • Powerful analysis tool that enables both detection of circuit breaker defects and trending of performance against key parameters from imported CBTrip records

What can Replay Pro? do?

  • Effecient storage, retrieval & analysis of records
  • Records can be graphed and overlaid for analysis
  • Data export option to MS Excel

CBTrip Offline Kit

The CBTrip can be used in an offline mode to measure the main contact times when the circuit breaker is isolated from the network or is being tested at another location such as the manufacturer’s premises or a maintenance workshop.

Test Connections

The schematic diagram in Figure 2 shows how the CBTrip is connected for an offline test. Normally a primary earth is left on one side of the isolated circuit breaker to provide a common connection for the Offline unit. Entering test details and selecting the test mode (Trip or Close) on the CBTrip is exactly the same as for an online test. The CBTrip automatically detects that it is an offline test and puts a symbol on the test result to indicate this.

Key Features of CBTrip

A summary of the key features which make the CBTrip an easy to use handheld device:

  • Can measure the Total Trip Time
  • Overlay of 4 Trip Coil Overlays for onsite analysis
  • Can be powered from rechargable batteries
  • Capture multiple fault operations
  • Upload previous records for comparison
  • Save breaker details from asset management system
  • Software upgrades available from the Support Centre

Combined Relay & Circuit Breaker Testing

Traditionally circuit breakers and protection relays are tested separately. However when a circuit breaker is called upon to operate under fault conditions, it is the combination of the protection relay and circuit breaker tripping mechanism that must operate together to ensure that the fault is isolated.

Effective protection discrimination relies on the total tripping time (relay tripping time & circuit breaker operating time) operating within a set timeframe.

Relay timing is achieved by injecting current using a secondary injection set connected to the CT secondary wiring. When the protection relay operates, this then triggers the CBTrip to capture the other circuit breaker parameters: Latch, Buffer, Auxiliary contact time (Acon), Main contact time (Mcon), DC supply voltage, as well as the relay trip time.

Profile Analysis

The current 'profile' allows diagnosis of potential defects in the trip coil mechanism and also highlights problems within the main circuit breaker contacts.

Each circuit breaker type has a characteristic profile similar to that shown below. Deviations from this profile can be easily detected by comparing profiles from first trip operations with subsequent or previous trip coil profiles. The same methodology can be applied to the close coil operation.