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Siemens 3VA1225-5FF42-0AJ0 — Molded Case Circuit Breakers (MCCB)

Siemens 3VA1225-5FF42-0AJ0 SENTRON MCCB, 125 A, 4-Pole, TM24

MPN3VA1225-5FF42-0AJ0

Siemens SENTRON 3VA1225-5FF42-0AJ0, molded case circuit breaker, 4-pole, 125 A, TM240 thermal-magnetic release, line protection, 70 mm depth, 140 mm width, 158 mm height.

Source DocumentedChannel stated on listing & quote
Condition PhotosReal unit photos / video on request
WhatsApp AnswersFast human replies for machine-down parts
Worldwide DispatchDHL/FedEx — transit quoted per order
Independent China distributor & sourcing agent· Listing updated Sep 2026

Specifications

3VA1225-5FF42-0AJ0 — Identification
ParameterValue
Product designationMolded case circuit breaker
Brand / rangeSENTRON
Basic switch (supplied) ref.3VA12255FF420AA0
Integrated auxiliary / alarm switch ref.3VA9988-0AB11
3VA1225-5FF42-0AJ0 — Ratings
ParameterValue
Number of poles4
Rated operational voltage Ue (AC)690 V
Rated insulation voltage Ui800 V
Current at 40 °C250 A
Current at 45 °C250 A
Current at 50 °C250 A
Current at 55 °C243 A
Current at 60 °C237 A
Current at 65 °C230 A
Current at 70 °C223 A
Switching capacity classM
Breaking capacity at 240 V187 kA
Breaking capacity at 415 V121 kA
Breaking capacity at 440 V75.6 kA
Breaking capacity at 500 V30 kA
Breaking capacity at 690 V17 kA
Power loss, max.57 W
3VA1225-5FF42-0AJ0 — Protection & Trip Unit
ParameterValue
Overcurrent release (trip unit) typeTM240
Overcurrent protection functionLI
Ground-fault monitoringWithout
Grounding protection functionNo
3VA1225-5FF42-0AJ0 — Construction & Connection
ParameterValue
Main circuit connection typenut keeper kit on both ends
Main circuit connector arrangementFront terminal
Protection class (IP), frontIP40
3VA1225-5FF42-0AJ0 — Accessories & Functions
ParameterValue
Undervoltage releaseNo
Voltage triggerNo
Trip indicatorYes
Communication functionNo
Measurement functionNo
Motor drive optionYes
Auxiliary CO contacts3
3VA1225-5FF42-0AJ0 — Environmental
ParameterValue
Operating temperature, max.70 °C
Operating temperature, min.-25 °C
Storage temperature, max.80 °C
Storage temperature, min.-40 °C
3VA1225-5FF42-0AJ0 — Mechanical
ParameterValue
Mechanical service life (operating cycles), typ.20 000
Height158 mm
Width140 mm
Depth70 mm
Height (in)6.22 in
Width (in)5.51 in
Depth (in)2.76 in

Product details

The interrupting capacity runs 187 kA at 240 V AC, 121 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V — that's enough headroom for most low-voltage switchgear applications where fault currents can spike. This is a line-protection design (not motor protection), meaning it's intended for feeder circuits, busbars, and distribution — not for direct motor overload duty where a separate overload relay would be needed.

Current derating and thermal limits

The breaker carries 125 A continuously up to 50 °C ambient without derating. Above that, it steps down: 243 A at 55 °C, 237 A at 60 °C, 230 A at 65 °C, and 223 A at 70 °C.

Physical fit and auxiliary wiring

That alarm contact is useful for remote fault annunciation without tying up a PLC input on the main contactor.

Frequently asked questions

Where can I buy 3VA1225-5FF42-0AJ0 and how do I get a price?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time.

What is 3VA1225-5FF42-0AJ0's listed depth?

The depth is 70 mm (2.76 in). Width is 140 mm (5.51 in), height is 158 mm (6.22 in).

What interrupting capacity does this MCCB have at 415 V?

At 415 V AC the interrupting capacity is 121 kA. At 240 V it's 187 kA; at 440 V it's 75.6 kA; at 500 V it's 30 kA; at 690 V it's 17 kA.

MPN
3VA1225-5FF42-0AJ0