Siemens
Siemens 5SX21 Miniature Circuit Breaker
Siemens 5SX21 Miniature Circuit Breaker
● In Stock
12-Mo Warranty
Same-Day Dispatch
Ships Worldwide
🎖 Veteran-Owned
In Stock — Ready to Ship
Get a price for 5SX21
Response within 1 business hour
12-month warranty
All units tested
Same-day dispatch
Order by 2pm CST
Worldwide delivery
US, EU, Asia, Middle East
Veteran-owned
CAGE: 9NK75
Compact design
C-curve tripping
Overcurrent protection
Short circuit protection
DIN rail mountable
Product description
The Siemens 5SX21 is a miniature circuit breaker designed for reliable protection of electrical circuits. It features a C-curve tripping characteristic, suitable for various applications.
This circuit breaker is commonly used in residential, commercial, and industrial settings for safeguarding lighting, appliance, and control circuits from overcurrents and short circuits.
Source your Siemens 5SX21 miniature circuit breakers from Stanlo Automation, your trusted veteran-owned distributor. We offer competitive pricing and quick delivery.
Technical specifications
| Poles | 1 |
| Tripping Characteristic | C |
| Voltage Rating | 230/400V AC |
Common applications
Residential wiring
Commercial buildings
Industrial control panels
Lighting circuits
Appliance protection
Compatible systems
Compatible with standard DIN rail mounting systems.
Also known as
Siemens 5SX21 MCB, Siemens Miniature Circuit Breaker
Replaces / compatible with
The Siemens 5SX21 series is a direct replacement for older Siemens models in the same series and can be used as a substitute for similar C-curve miniature circuit breakers from other manufacturers, provided specifications match.
Technical note
Expert tip
Ensure proper wire termination and torque for reliable operation and safety.What happens next?
1
Email confirmation
Immediate receipt acknowledgment sent to you
2
Account manager assigned
Confirms your part's spec and condition
3
Your quote delivered
Tailored to your specific requirements
Frequently asked questions
What is the tripping characteristic of the Siemens 5SX21 circuit breaker?
The Siemens 5SX21 circuit breaker features a C-curve tripping characteristic. This means it is designed to trip between 5 to 10 times the rated current, making it suitable for circuits with moderate inductive loads or inrush currents.