Request the breaker rating and application together
For a high-voltage live-tank or other circuit breaker, send the voltage class, continuous current, interrupting duty, operating mechanism and controlling specification. For mains, ties and feeders in a switchboard, identify the complete assembly and protection requirements.
High-voltage and generator circuit breakers for sale
J&J accepts substation circuit-breaker and generator circuit-breaker requirements. For live-tank, dead-tank, SF6 or vacuum breaker inquiries, send the required type, rated maximum voltage, continuous current, interrupting duty, control voltage, model and quantity. No public breaker lot is currently listed; a written offer confirms equipment, condition and availability.
How does a generator breaker differ from a substation breaker requirement?
The generator and transformer interface has its own fault-current and operating-duty requirements. Identify the installed position and governing specification, then review the applicable generator-source and system-source fault duties, continuous current, insulation levels, control system and physical interfaces with the project engineer. A matching kV label alone is insufficient.
- Coordinate breakers, generators and transformers
- Substation power transformer supply
- Generator step-up transformer supply
Request live-tank or dead-tank high-voltage circuit breakers
Specify the required live-tank or dead-tank construction, manufacturer/model, rated maximum voltage, continuous current, interrupting duty, insulation levels, frequency, mechanism, control voltage, quantity and site interfaces. Requests for an ABB / Hitachi or Siemens SF6 breaker need the specific model and equipment records; no model is advertised as available without a current written offer.
Which circuit breakers can I request from J&J?
Send requirements for high-voltage substation breakers, medium-voltage distribution breakers, generator circuit breakers (GCBs), or breakers within a switchgear package. Include your preferred OEM and model when replacing an existing unit. Requests for 138, 230 or 345 kV systems should include the equipment's required rated maximum voltage, not just the system's nominal voltage.
What should I send for a circuit-breaker quote?
Start with the nameplate or specification, one-line diagram, quantity, project location and needed-on-site date. If a rating is unknown, mark it as not sure so the open item stays visible.
- Electrical: rated maximum voltage, continuous current, interrupting current, frequency and insulation requirements.
- Configuration: breaker type, mounting or switchgear interface, mechanism, control voltage, connections and included accessories.
- Project: acceptable condition, required records and tests, equipment-only or package scope, and delivery requirements.
Which records should a high-voltage breaker offer include?
A useful breaker offer connects one identifiable unit to its ratings, configuration, condition and interface records. Ask for the nameplate and serial identity first, then reconcile drawings, mechanism and control information, test history, included accessories and shipment scope. Missing records should be listed as open items rather than treated as confirmed.
| Record | What the buyer should verify |
|---|---|
| Identity | OEM, type or model, serial number, manufacture year if shown, and clear photos of every nameplate. |
| Electrical ratings | Rated maximum voltage, continuous current, interrupting rating, frequency, insulation level and duty-cycle information stated in the controlling specification. |
| Mechanism and controls | Operating-mechanism type, control and auxiliary voltages, trip and close coils, motor data, heaters, auxiliary contacts and wiring diagrams. |
| Physical interface | General arrangement, mounting, terminals or bushings, connector details, dimensions, weights and any required existing-lineup interface. |
| Condition and service | Storage or installed status, operation count if available, maintenance and service records, inspection findings, repairs, modifications and known deficiencies. |
| Tests and manuals | Available factory and field test reports, instruction manuals, certified drawings and document revision numbers tied to the offered unit. |
| Included scope | Breaker, mechanism, cabinets, structures, bushings, monitors, accessories, spares, special tools, gas or other dielectric-handling scope, and explicit exclusions. |
| Logistics and terms | Current location, preservation, dimensions and weights, loading responsibility, shipment condition, inspection access, release date and commercial basis. |
For worksheets, specifications or supporting documents, call 346-276-9540 or email tommy@jjtransformers.com. Files are shared directly after contact.
How should a replacement breaker be screened?
Screen the replacement against the controlling project specification and the exact existing interface—not only nominal system voltage. Build a requirement-versus-offer table for ratings, mechanism, control power, terminals, dimensions, protection and included scope; record every deviation and leave final compatibility approval with the responsible engineer and equipment owner.
For an existing lineup, request the original manufacturer drawings, breaker and mechanism nameplates, wiring diagrams, interlock details, cubicle or structure information, recent test results and photographs of the primary and secondary connections. A similar model name does not prove interchangeability.
For a standalone high-voltage breaker, coordinate the breaker with the bus, disconnects, CTs, protection, control house, foundations, structures, grounding, line or transformer terminals and the site's operating duty. State which items are included in the equipment offer and which remain project scope.
Need a breaker with a GSU, generator or substation package?
Send the complete equipment list and identify what is already supplied. J&J can screen the transformer, generation and breaker requirements together. Generator circuit breakers require application-specific review; a matching kV or current label alone does not establish suitability. Your responsible engineer approves the final equipment and interfaces.
New Eaton equipment. 9–11 weeks total to your site.
For new manufacturing, J&J can quote Eaton pad-mounted and dry-type transformers up to 10 MVA / 10,000 kVA, medium-voltage switchgear, switchboards, breakers, busway, unit and prefabricated substations, and UPS systems. The 9–11 week total delivery window covers all listed OEM equipment through arrival at your site. Freight, import clearance and applicable import duties are included in the confirmed delivered quotation; the firm order schedule is confirmed in writing.
Individual breakers or a complete switchboard?
For a 4000A main or tie breaker, identify the required model, voltage and application. For a complete low-voltage switchboard, include the assembly rating, main/tie/feeder quantities, controls and enclosure. A component quotation alone does not supply the whole lineup.
Circuit breaker price and compatibility requests
A circuit breaker for sale request needs voltage, continuous current, interrupting duty, operating mechanism, control power and application. For generator circuit breakers, include generator-side duty and the project's specific requirements rather than treating a general-purpose breaker as automatically equivalent.
- For replacement breakers, provide manufacturer, model, drawings, mounting or drawout interface, trip/relay requirements and interlocks.
- Request condition, maintenance and available test records; confirm the actual device and included mechanism or accessories.
Common questions
Written quotes and supporting records control unit-specific ratings, availability, condition, price, and delivery.
Can J&J quote a live-tank or dead-tank circuit breaker?
J&J accepts substation circuit-breaker and generator circuit-breaker requirements. For live-tank, dead-tank, SF6 or vacuum breaker inquiries, send the required type, rated maximum voltage, continuous current, interrupting duty, control voltage, model and quantity. No public breaker lot is currently listed; a written offer confirms equipment, condition and availability. Email tommy@jjtransformers.com or call Tommy Marco at 346-276-9540 for the exact equipment record, price and written availability.
Can I request a circuit breaker that is not in your inventory?
Yes. Call Tommy Marco at 346-276-9540 or send a breaker request with your ratings, quantity and required date. J&J will check supply options; a request does not guarantee availability or reserve equipment.
Can I request a complete substation?
Send the one-line and equipment list, including transformers, breakers, switchgear and controls. J&J reviews the equipment supply scope. Engineering, civil work, installation and commissioning are included only when explicitly stated in a written agreement.
What should I send first for a 138 kV, 230 kV or 345 kV breaker request?
Send the controlling specification or nameplate, required rated maximum voltage, continuous current, interrupting rating, frequency, breaker type, quantity, project location and needed-on-site date. For a replacement, add the existing model, mechanism, control voltage, drawings and interface photos.
Does matching voltage make a breaker interchangeable?
No. The responsible engineer must also review current and interrupting ratings, insulation requirements, operating duty, mechanism and control power, physical and electrical interfaces, protection, condition and the applicable project standards.
Can J&J review surplus or used high-voltage breakers?
Yes. J&J can review an owner- or authorized-seller package when unit identity, ratings, location, condition, records, photos, included scope and commercial expectations are available. Review does not guarantee a purchase, sale or project match.
Does J&J manufacture or certify circuit breakers?
No. J&J Transformers LLC supplies and screens power equipment but is not the OEM or engineer of record. The buyer, responsible engineer and relevant authorities approve the final application, studies, installation and commissioning.
What do I need to quote a replacement or generator circuit breaker?
Send the existing device's nameplate/model and drawings, voltage/current/interrupting duty, control power, mechanism, protection, interface and project application. For a generator breaker, include generator and transformer data so the responsible engineer can review the full duty.