Metal-Clad Switchgear & Vacuum Circuit Breakers
Ryan Sales supplies metal clad switchgear and vacuum circuit breakers from JST for 5 kV to 15 kV distribution. The J100CLAD lineup uses magnetically actuated J3MAG breakers, and the OD3MAG outdoor breaker covers substation and recloser-replacement duty up to 15.5 kV. We work with utilities, plants and contractors in Texas and Oklahoma, and on data center projects nationwide.
Send the voltage, ampacity and fault duty. A rep will narrow it down.
JST Power EquipmentJ100CLAD Air-Insulated Metal-Clad SwitchgearIEEE-rated metal-clad air-insulated switchgear with magnetically actuated J3MAG vacuum breakers for 5-15 kV distribution.- Voltage class
- 5–15 kV
- Continuous current
- Up to 3000 A
- Symmetrical interrupting
- 25–50 kA
JST Power EquipmentJ3MAG Vacuum Circuit BreakerMagnetically actuated vacuum circuit breaker with independent pole actuators for the J100CLAD switchgear line.- Voltage class
- 5–15 kV
- Interrupting time
- 3 cycles
- Operating mechanism
- Magnetic actuation, independent pole actuators; no lubrication
JST Power EquipmentOD3MAG Outdoor Substation BreakerOutdoor medium voltage substation breaker that combines circuit breaker ratings with recloser functionality, configurable single- or three-phase.- Maximum voltage
- 15.5 kV
- Continuous current
- 1250 / 2000 A
- Symmetrical interrupting
- 31.5 kA
How to choose metal-clad switchgear & vacuum circuit breakers
Indoor lineup or outdoor breaker
Decide first whether you need a switchgear lineup or a standalone outdoor breaker. The J100CLAD is IEEE-rated metal-clad, air-insulated switchgear with drawout breakers in grounded compartments, suited to plant, generation, commercial and data center distribution. The OD3MAG is a self-contained outdoor breaker in a NEMA 4, IP55 enclosure for utility substations, solar and wind collection, and rail.
Interrupting rating and continuous current
Size the breaker to the available fault current at the bus and the load it must carry, with margin for future growth. The table shows the published ratings.
| Model | Type | Voltage | Continuous | Interrupting |
|---|---|---|---|---|
| J100CLAD | Indoor metal-clad switchgear | 5-15 kV | Up to 3000 A | 25-50 kA |
| J3MAG | Vacuum breaker for J100CLAD | 5-15 kV class | Per lineup rating | Per lineup rating |
| OD3MAG | Outdoor substation breaker | 15.5 kV max | 1250 A / 2000 A | 31.5 kA sym / 43 kA asym |
The OD3MAG also lists 82 kA peak withstand, 125 kV BIL and 50 kV power frequency withstand, and it runs an O-0.3s-CO-15s-CO duty cycle.
Magnetic actuation and operating mode
Magnetic actuators replace the spring-charging mechanism with far fewer moving parts. The J3MAG uses independent pole actuators, needs no lubrication and operates in 3 cycles. Independent poles also allow single-phase or three-phase operation, which lets a feeder breaker behave more like a recloser when the protection scheme calls for it. The OD3MAG is configurable single- or three-phase and combines breaker ratings with recloser functionality, which is why it appears on recloser-replacement and substation retrofit jobs.
Controls, instrument transformers and environment
Confirm control power and sensing before you lock the spec. The OD3MAG accepts 48 or 125 Vdc or 120 Vac control, offers CT or Rogowski coil options, and is rated from -40C to +50C, which covers West Texas and Oklahoma outdoor sites. The J100CLAD includes integral racking and is non-arc-resistant, so check whether your specification requires arc-resistant construction before selecting it.
Lead time
Metal-clad lineups and outdoor breakers are built to order, and factory schedules move month to month. Ask your rep for current lead times on the J100CLAD and OD3MAG before you lock the project schedule, and see the lead-times guide below for market context.
For deeper background, read Medium Voltage Equipment Lead Times and Medium Voltage Equipment for Data Centers, compare compact options under Gas-Insulated Switchgear, or request a quote.
Frequently asked questions
Metal-clad vs metal-enclosed switchgear?
Metal-clad switchgear is a stricter type of metal-enclosed switchgear, defined by IEEE C37.20.2. It uses drawout circuit breakers, grounded metal barriers between the breaker, bus and cable compartments, insulated bus and automatic shutters over the primary contacts. Metal-enclosed switchgear, under IEEE C37.20.3, usually uses load interrupter switches and fuses, with less separation between compartments. JST's J100CLAD is IEEE-rated metal-clad switchgear for 5 to 15 kV, with ratings up to 3000 A.
Can a magnetic-actuator breaker retrofit older switchgear?
Yes, often. Many older breakers can be replaced with magnetic-actuator vacuum breakers built to fit the existing cell. The replacement must match the cell's racking, interlocks, secondary contacts, bus connections and ratings, and it should be tested as a matched assembly. Magnetic actuators have fewer moving parts than spring mechanisms and need no lubrication, so they cut maintenance. JST's J3MAG, for 5 to 15 kV, uses independent magnetic actuators on each pole. Ryan Sales can check whether your switchgear is a good candidate.
What are current switchgear lead times?
Switchgear lead times depend on the factory's backlog, how custom the design is, and the supply of parts such as vacuum interrupters, relays and copper. Arc-resistant construction, unusual ratings and long drawing-approval cycles add time, while standard designs and quick approvals save it. Ordering early and settling ratings early give the most schedule control. Lead times change often, so Ryan Sales can get current factory lead times for JST metal-clad switchgear and breakers on request.