ABB EntelliGuard G low-voltage power circuit breaker
Manufacturer: ABB
ABB EntelliGuard G power breakers, 400-6,000 A GE-heritage frames with parts still fully available
This model is part of SecondWatt’s switchgear research catalogue. Specifications and price observations are included where supported by sources. Equipment availability and commercial terms require confirmation.
ABB EntelliGuard G dossier: 400-6,000 A GE-heritage breakers to 200 kAIC, RELT arc reduction, used pricing 3,500-35,000 USD, inspection checklist.
EntelliGuard G is the GE-heritage LV ANSI power circuit breaker launched around 2008 and now sold by ABB as a previous-generation product in limited phase, with all parts and replacement breakers still fully available per the official product page. For new designs ABB points to Emax 2 and Emax 3; for the large installed base, EntelliGuard R Retrofill units cover legacy AK/AKD frames.
Ratings run 400-6,000 A in 3- and 4-pole builds with interrupting capability to 200 kAIC under ANSI/UL 1066 and UL 489, IEC variants included. The EntelliGuard TU trip unit carries the RELT arc-energy-reduction setting (maintaining HRC1/2 protection up to 100 kA faults), zone-selective interlocking, and Modbus RTU or Profibus DP communications.
The secondary market is priced across the frame range: a 400 A unit new-open-box at 3,500 USD, a 5,000 A electrically-operated frame refurbished with 1-year warranty at 35,000 USD, with Breaker Outlet and Bullock stocking mid-frames. As Emax 3 succession pressure builds, the EntelliGuard G installed base becomes a retrofit and spares annuity.
Why it matters
A 200 kAIC ANSI breaker family with OEM parts still flowing is the sweet spot of the used market: high replacement value, low platform risk. The observed 10x price spread (3,500 USD small frame to 35,000 USD warranted 5,000 A unit) shows how frame size, operation type, and warranty drive value, a pricing curve no published source tracks except listings.
Who buys it
Owners of GE/ABB LV switchgear built 2008-2020 buy spares and replacements; contractors buy tested units to restore lineups without waiting 54 weeks on new-build LV switchgear. Retrofit buyers use EntelliGuard R to modernize older AK/AKD lineups, keeping cell iron while replacing the breaker.
Role in the data center
Main and feeder breakers in GE and ABB low-voltage switchgear lineups of the 2008-2020 build era, sitting between the unit substation and the UPS and mechanical distribution boards. Tested spares and replacements keep those lineups serving critical load without a 54-week wait for new low-voltage switchgear.
Key specifications
| Current range | 400-6,000 A |
|---|---|
| Interrupting ceiling | 200 kAIC |
| Standards | ANSI/UL 1066, UL 489, IEC |
| Trip unit | EntelliGuard TU with RELT |
| RELT capability | HRC1/2 to 100 kA faults |
| Status | previous generation; parts fully available |
| Observed 400 A open-box | 3,500 USD OBO |
| Observed 5,000 A refurbished | 35,000 USD OBO (1-yr warranty) |
| Retrofit line | EntelliGuard R Retrofill (AK/AKD) |
| Communications | Modbus RTU and Profibus DP; zone-selective interlocking |
| Pole configurations | 3-pole and 4-pole |
Technical summary
Range: 400-6,000 A, 3P/4P. Interrupting: up to 200 kAIC. Standards: ANSI/UL 1066, UL 489, IEC variants; UL/cUL/CE. Trip unit: EntelliGuard TU with RELT arc-energy reduction. RELT protection: HRC1/2 up to 100 kA faults. Communications: Modbus RTU, Profibus DP; zone-selective interlocking. Status: previous generation, limited phase; parts fully available. Retrofit sibling: EntelliGuard R Retrofill for AK/AKD frames. Heritage: GE (launched ~2008); ABB-owned since 2018.
Major variations
Frame builds from 400 to 6,000 A, manually or electrically operated, fixed or draw-out, across S, N, H and M class interrupting tiers, in ANSI/UL 1066 and IEC versions. Trip-unit level is the other axis: EntelliGuard TU units differ in metering, communications and whether the RELT arc-energy-reduction setting is fitted. EntelliGuard R Retrofill is a separate replacement breaker for legacy GE AK and AKD cubicles, and the EntelliGuard E breaker is a different product restricted to Entellisys switchgear.
Configurations and options
Price moves on four order variables: frame ampere rating from 400 to 6,000 A; interrupting class within the frame, in S, N, H and M tiers up to 200 kAIC, so two breakers of the same ampere rating can differ by tens of kA; manual or electrical operation and fixed or draw-out construction; and trip-unit level, meaning whether the EntelliGuard TU carries metering, communications and the RELT arc-energy-reduction setting. Pole count is 3 or 4, and ANSI/UL 1066 and UL 489 builds sit alongside IEC versions. On a used unit the trip-unit level and the operation type move price more than frame size does.
Compatibility and dependencies
Unlike the Entellisys-only EntelliGuard E, the G is platform-independent, but the cassette still governs: a G will not seat in an EntelliGuard E cell, and the EntelliGuard R Retrofill is a separate replacement breaker built to drop into legacy GE AK and AKD cubicles. Downstream integration runs through the EntelliGuard TU, which offers Modbus RTU or Profibus DP plus zone-selective interlocking, so the power monitoring system has to speak one of those rather than an Ethernet protocol. Interrupting capability up to 200 kAIC has to be coordinated against the available fault current at the board, and control voltage and secondary disconnects must match the existing cubicle.
Pricing and availability
Comparable secondary-market band: 3500–35000 $ per breaker. Trend: rising Electrical Trader's 2026-04-01 review reports circuit breakers up 47% since 2021 at category level. Two dated model observations bracket the frame range, both logged 2026-08-18: a 400 A GN04ND new-open-box at 3,500 USD and a warranted refurbished electrically operated 5,000 A GB50MX at 35,000 USD. The spread reflects condition, operation type and trip-unit level as much as frame size. ABB's limited-phase status with parts still available supports the floor, since an installed lineup can be kept serviceable rather than replaced. Lead time, new: Replacement breakers ship via ABB (limited phase). Lead time, used or refurbished: 1-4 weeks (dealer stock). Warranty, used: 1-year typical from reconditioning dealers.
Lifecycle and maintenance
LV power circuit breakers serve 30-40 years on 3-5 year maintenance cycles per ANSI/NETA MTS and NFPA 70B, with mechanism lubrication and injection testing the critical items. A deep reconditioning ecosystem (Relectric, NAS, Bay Power, Bullock) tests to NETA specifications and warrants units for 1 year. OEM trip-unit retrofit programs (Eaton PXR, ABB EntelliGuard R, Siemens 3WA retrofit) extend installed platforms past electronics obsolescence, which sustains used-breaker values.
Thermal and emissions profile
Switchgear produces no combustion emissions; the regulatory profile is electrical safety and materials. NFPA 70B became a standard in its 2023 edition, making maintenance programs mandatory rather than recommended, and arc-flash rules (NFPA 70E) govern work practices. LV air-insulated gear carries no F-gas exposure, and construction standards (UL 891, UL 1558, IEEE C37.20.1) plus arc-resistant options under IEEE C37.20.7 define the safety envelope buyers should verify.
Common failure points
- Mechanism springs and lubrication — Slow trips, trip-free on close, failure to latch on aged units
- Trip unit electronics — Nuisance trips or no-trip from aged or obsolete electronics
- Contacts and arc chutes — Overheating and interruption failure from eroded contacts or cracked chutes
- Secondary wiring — Control faults from damaged secondary disconnects and aux switches
- Provenance and counterfeits — Counterfeit or mis-labeled breakers fail catastrophically under fault
- Cassette and racking wear — Misalignment and cluster contact damage on worn cradles
Inspection checklist
Mechanism: exercise open/close 10+ cycles; verify the charge/close/trip sequence completes and the mechanism latches on every close; treat any failure to latch on close as a finding and check it against the OEM acceptance procedure. Trip curve: primary injection test; NETA field data shows 22% of LV power breakers off their published curves. Secondary injection: verify all 4 protection functions (LSIG) against settings; record as-found/as-left values. Contact resistance: micro-ohm test each pole; investigate readings above 1.5x sister poles. Insulation resistance: megger at 1,000 V per ANSI/NETA MTS acceptance tables. Contact wear: inspect arcing contacts and wear indicators against the OEM replacement limit. Arc chutes: remove and inspect for cracks, erosion, and metal splatter; replace damaged chutes. Lubrication: verify mechanism grease condition; dried lubricant is the leading slow-trip cause on 20+ year units. Racking: exercise draw-out mechanism through connect/test/disconnect; verify shutter operation.
Procurement channels
NAS Circuit Breakers sells warranted refurbished frames through eBay, with Alpha 7, Breaker Outlet and Bullock Breakers stocking mid-range frames; ABB still ships new replacement breakers and parts while the limited-phase production continues. Buyers should confirm trip-unit level and operation type on any listing, since both move the price more than frame size alone.
Regional notes
Built to ANSI/UL 1066 and UL 489 for North America with UL, cUL and CE marks, and offered in IEC versions as well, so a used unit's listing standard has to be read off the nameplate rather than assumed from the model name. ABB lists the line as previous generation in limited phase with parts and replacement breakers still available, and directs new North American design work to Emax 2 and Emax 3. Gray-channel export stock trades below US distributor levels and carries no verifiable warranty position.