Circuit breaker test equipment & analysers
Circuit-breaker test equipment assesses the mechanical and electrical condition of high- and medium-voltage circuit breakers — timing, motion, contact resistance and coil behaviour — to confirm the breaker will clear a fault correctly. The Amperis range for the electrical sector includes circuit-breaker analysers for substation commissioning and predictive maintenance.
What it measures and how it works
A circuit-breaker analyser captures every pole simultaneously while the breaker operates. It records contact timing (open, close, close-open and pole synchronism, to the millisecond), travel and velocity from a motion transducer, dynamic and static contact resistance (down to the micro-ohm — healthy main contacts typically sit well below 50 µΩ), and coil current signatures that reveal mechanism and trip-circuit problems. A first-trip test records the as-found state before the breaker is exercised.
How to choose the right analyser
- Match the channel count to your breakers (poles × interrupters per pole).
- Look for a built-in micro-ohmmeter (≥100 A) for static contact resistance, plus dynamic resistance (DRM).
- Check motion-sensor support (linear and rotary) and configurable velocity calculations.
- Prioritise dual-ground safety, a first-trip/minimum-pickup module and clear pass/fail reporting.
- Favour PC software for trending across maintenance cycles.
Not sure which analyser fits your fleet? Do not hesitate to contact us.
Applications
- HV and MV circuit breakers (SF6, vacuum, oil, air)
- Gas-insulated switchgear (GIS)
- Substation acceptance and routine maintenance
- Post-fault and condition-based diagnostics
- Mechanism and trip-circuit troubleshooting
Applicable standards
Amperis instruments are referenced to IEC/EN standards (not national PN/PL designations):
- IEC 62271-100 — high-voltage AC circuit-breakers
- IEC 62271-1 — common specifications, including contact resistance
- IEEE C37.09 — test procedures for AC HV circuit breakers
- ANSI/NETA ATS/MTS — field acceptance and maintenance values
- IEC/EN 61010-1 and IEC/EN 61326-1 — instrument safety and EMC
Frequently asked questions
What does a circuit-breaker analyser actually measure?
The core parameters are contact timing, contact travel and velocity, static and dynamic contact resistance, and coil current. Together they show whether the interrupter and operating mechanism still perform within specification.
What contact resistance is acceptable?
Static main-contact resistance is usually well under 50 µΩ; compare each test to the breaker’s baseline. Dynamic resistance (DRM) can reveal eroded or misaligned contacts even when the static value still looks normal.
Why run a first-trip test?
A first-trip test captures the breaker exactly as found, before any exercising. It exposes lubrication, friction or timing problems that disappear once the mechanism has been operated a few times.
Technical resources
Pair breaker analysis with SF6 gas tools, coil testing and micro-ohmmeters, or explore transformer test equipment. Request a quote and our engineers will configure the right analyser.