Zinsco / Sylvania SJK-3C-350 Molded Case Circuit Breaker
- 350A
- 3 Pole
- Bolt-On
Quantity
Zinsco / Sylvania SJK-3C-350 - 350A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Operating as a crucial safety component for industrial facilities, this 350A thermal-magnetic breaker delivers reliable LI protection. The unit accommodates large wiring, making it highly adaptable for heavy commercial loads. It fastens securely into legacy Challenger, Westinghouse, and Sylvania panelboards to keep older systems running smoothly. When sourcing modern equivalents, the Eaton KD3350 serves as the replacement path. A 30kA rating at 480VAC ensures superior defense against faults.Specifications
| Brand | Zinsco / Sylvania |
|---|---|
| Part Number | SJK-3C-350-R |
| Series | SJK |
| Amperage | 350A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Sylvania Panelboards, Challenger Panelboards, Westinghouse Panelboards, Eaton Panelboards |
| Wire Gauge | 3/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 3/0 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Lug Kits |
|---|---|
| Accessories | Lugs Not Included |
| Standards | UL 489, NEMA AB 1 |
| Approval | UL |
| Temp Rating | 40°C |
| Construction Features | Interchangeable Trip Unit |
Product FAQs
6 answersWhich legacy panelboards accept the SJK-3C-350 circuit breaker?
This bolt-on breaker is engineered for installation in aging commercial panelboards manufactured by Sylvania, Challenger, Westinghouse, and Eaton.
What wire sizes and materials are supported by the terminals on the SJK-3C-350?
The breaker comes equipped with lugs that accommodate 3/0 AWG to 500 kcmil conductors. Both aluminum and copper (Al/Cu) wiring can be used.
Are the thermal and magnetic trip settings adjustable on the SJK-3C-350?
The thermal-magnetic trip unit features a fixed thermal element for long-time protection and an adjustable magnetic element for instantaneous short-circuit protection.
Can I use the Sylvania SJK-3C-350 to replace a Challenger SJK3C350?
Yes, Sylvania and Challenger shared the same SJK frame design. The Sylvania SJK-3C-350 serves as a direct drop-in replacement for the Challenger SJK3C350.
What is the modern Eaton equivalent for the SJK-3C-350?
When upgrading legacy systems or sourcing modern equivalents, the Eaton KD3350 is the standard replacement path for this 350A thermal-magnetic breaker.
What are the maximum fault current ratings for the SJK-3C-350 across different voltages?
The breaker provides a maximum interrupting capacity of 65kA at 240VAC, 30kA at 480VAC, and 22kA at its maximum rated voltage of 600VAC.
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