STM6 Thermal-Magnetic MCCB
STM6 thermal-magnetic MCCB for distribution and motor protection, covering 10A to 2000A across 125A to 2000A frames with C, S, M and H breaking-capacity options.
Order Support
- Typical production lead time: 20 working days
- Free samples — send us your express shipping account
- Technical documents checked for the requested model
- Pre-shipment inspection options can be agreed before ordering
- OEM and private-label requirements are reviewed case by case
STM6 thermal-magnetic MCCB for distribution and motor protection, covering 10A to 2000A across 125A to 2000A frames with C, S, M and H breaking-capacity options.
Overview
The STM6 series is our core thermal-magnetic MCCB line: bimetal-plus-magnetic protection for overload and short circuit, built for distribution and motor protection in industrial and building installations.
Key Features
- Thermal-magnetic overload and short-circuit protection
- 10A to 2000A rated-current range
- AC230V / AC400V / AC690V listed configurations
- 1P to 4P construction, frame dependent
STM6 Thermal-Magnetic MCCB
| Parameter | 125 | 160 | 250 | 400 | 630 | 800 | 1250 | 2000 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | S | M | H | C | S | M | H | C | S | M | H | S | M | H | M | H | M | H | S | M | H | M | H | |
| Frame size In (A) | 10A~125A | 16A~160A | 100A~250A | 250A~400A | 500A~630A | 500A~800A | 800A~1250A | 1000A~2000A | ||||||||||||||||
| Number of poles | 1P, 2P, 3P, 4P | 2P, 3P, 4P | 3P, 4P | 3P, 4P | 3P, 4P | 3P, 4P | 3P, 4P | 3P, 4P | ||||||||||||||||
| Rated insulation voltage Ui (V) | 1000V | |||||||||||||||||||||||
| Rated impulse withstand voltage Uimp (kV) | 8kV | |||||||||||||||||||||||
| Rated operational voltage Ue (V) AC | 230V;400V; 690V | |||||||||||||||||||||||
| Breaking capacity code | C | S | M | H | C | S | M | H | C | S | M | H | S | M | H | M | H | M | H | S | M | H | M | H |
| Rated service short-circuit breaking capacity Ics (kA) AC230V | 5 | 15 | 35 | 50 | 7 | 10 | 25 | 35 | 20 | 25 | 40 | 50 | 25 | 40 | 50 | 40 | 50 | 65 | 70 | 40 | 65 | 70 | - | - |
| Rated service short-circuit breaking capacity Ics (kA) AC400V | 5 | 13 | 18 | 50 | 10 | 13 | 18 | 35 (2P) / 50 (3P,4P) | 10 | 15 | 35 | 50 | 15 | 35 | 65 | 35 | 65 | 50 | 65 | 35 | 50 | 65 | 50 | 85 |
| Rated service short-circuit breaking capacity Ics (kA) AC690V | 3 | 3 | 5 | 8 | 2 | 3 | 5 | 10 | 3 | 4 | 10 | 15 | 4 | 10 | 12 | 10 | 12 | 15 | 20 | 10 | 15 | 20 | 20 | 20 |
| Rated ultimate short-circuit breaking capacity Icu (kA) AC230V | 8 | 30 | 36 (2P) / 50 (3P,4P) | 50 | 10 | 20 | 30 | 50 | 30 | 50 | 65 | 70 | 50 | 65 | 70 | 30 | 50 | 80 | 85 | 65 | 80 | 85 | - | - |
| Rated ultimate short-circuit breaking capacity Icu (kA) AC400V | 8 | 25 | 36 | 50 | 15 | 25 | 36 | 50 | 15 | 30 | 50 | 65 | 30 | 50 | 65 | 50 | 65 | 65 | 85 | 50 | 65 | 85 | 50 | 100 |
| Rated ultimate short-circuit breaking capacity Icu (kA) AC690V | 5 | 6 | 10 | 15 | 8 | 6 | 10 | 15 | 5 | 8 | 15 | 20 | 8 | 20 | 25 | 10 | 20 | 25 | 35 | 20 | 25 | 35 | 20 | 25 |
| Mechanical life (operations) | 8500 | 8500 | 7000 | 4000 | 4000 | 2500 | 2500 | 2500 | ||||||||||||||||
| Electrical life (operations) | 1500 | 1500 | 1000 | 1000 | 1000 | 500 | 500 | 500 | ||||||||||||||||
| Width (mm) | 1P 25 / 2P 50 / 3P 75 / 4P 100 | 2P 60 / 3P 90 / 4P 120 | 3P 105 / 4P 140 | 3P 140 / 4P 184 | 3P 140 / 4P 184 | 3P 210 / 4P 280 | 3P 210 / 4P 280 | 3P 210 / 4P 280 | ||||||||||||||||
| Length (mm) | 130 | 155 | 165 | 257 | 257 | 275.5 | 275.5 | 340 | ||||||||||||||||
| Height (mm) | 68 | 68/82 | 68/88 | 103 | 103 | 103 | 103 | 141 | ||||||||||||||||
| Handle height (mm) | 94.5 | 94/108 | 96/116 | 152 | 152 | 152 | 152 | 244 | ||||||||||||||||
Typical Applications
- Distribution boards
- Motor protection
- Building installations
Frequently Asked Questions
What frame sizes are available in the STM6 series?
Eight frame sizes from 125A to 2000A, with rated currents from 10A to 2000A. The 400A–2000A frames come in M and H breaking types only.
What breaking capacity should I choose?
Four levels: C (basic), S (standard), M (higher), H (high). Icu ranges from 5kA to 100kA at AC400V. Select based on your prospective short-circuit current — we can help calculate it from your transformer size.
Which accessories can be fitted inside the breaker?
Alarm contacts, shunt trip, undervoltage release, single/double auxiliary contacts and their combinations — installable in either left or right compartment.
What operating methods are available?
Direct operation, motor operated (P1 universal or P2 DC6), and rotary handles (center or offset, round or square). Motor voltage options: DC24/110/220V, AC230/400V.
Can I get rear connection or plug-in mounting?
Yes — fixed front/rear, plug-in (split or one-piece) and draw-out versions are available across the range.
Request Quotation
Ask us to confirm price, MOQ, lead time and sample availability for this model.