Siemens SENTRON 3VL series

Questions and Answers

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Jamie AustinAug 9, 2025
Why does my Siemens SENTRON 3VL Protection Device circuit breaker keep tripping due to overload?
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  Matthew SparksAug 9, 2025
  If your Siemens Protection Device circuit breaker trips due to overload, it indicates the circuit breaker is working as intended. First, verify if the operating current exceeds the thermal tripping limit. Inspect the terminals for discoloration, as cables may loosen due to vibration or cold flow. High ambient temperatures can also cause tripping; consider derating the In or IR values if temperatures in enclosures are too high. Finally, if none of the above apply, inspect the overcurrent release for discoloration and ensure tightening torque values are correct.
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David DeckerAug 19, 2025
What to do if Siemens SENTRON 3VL circuit breaker trips due to short-circuit?
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  davidperryAug 19, 2025
  If the Siemens Protection Device circuit breaker trips because of a short-circuit, it could be due to excessive making current, such as from a motor. Try adjusting the magnetic trip rating to a higher setting until the breaker stops tripping when the motor starts. High current peaks, like those during star-delta starter transitions, can also cause this. In such cases, the short-circuit release "I" must be set to a higher value; however, note that this might reduce motor protection.
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Ashley CookNov 27, 2025
Why are the mechanical and electrical functions of my Siemens SENTRON 3VL affected?
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  barbara90Nov 27, 2025
  If the mechanical and electrical functions of your Siemens Protection Device are affected, high humidity or corrosion could be the cause. The molded case circuit breakers must not be used in environments with high humidity since this can cause dielectric and insulation problems. In such environments, appropriate measures need to be taken, such as placing the circuit breaker in an enclosure. Also, the molded case circuit breakers are not designed to be used in aggressive environments and should be installed in a housing. If the issue relates to internal accessories, determine the type installed by removing the circuit breaker cover and checking the order number. Then, verify their correct function. Ensure the correct voltage is connected to the undervoltage release, and that voltage is not ...

Summary

Configuration

Functional principle

Describes the mechanical design, current limiting, and joint trip units of the circuit breakers.

Functions

Protection functions

Covers overcurrent release, differential current protection, single-pole operation, and ground-fault protection.

Application planning

Use in motor protection

Covers optimal protection and direct starting of three-phase AC squirrel-cage motors.

Installing;mounting

Mounting and safety clearances

Locking devices

Connecting

Cables and busbars

Displays and operator controls

Overcurrent trip unit without LCD display

Overcurrent trip units with LCD display

Parameter assignment; addressing

Setting the parameters

Explains how to set parameters on the ETU, including tripping characteristics.

Service and maintenance

Preventive measures

Outlines inspection intervals and checks for circuit breaker maintenance.

Technical data

Motor Protection

Lists characteristic values for 3VL circuit breakers in motor protection.

Dimensional drawings

VL160 X (3 VL1), VL160 (3 VL2), and VL250 (3 VL3), 3- and 4-pole, to 250 A

VL400 (3 VL4), 3- and 4-pole, up to 400 A

Circuit diagrams

Circuit diagrams VL1... 8 motorized operating mechanism (MO)

Siemens SENTRON 3VL series Specifications

General

Rated voltage	Up to 690 V AC
Standards	IEC 60947-2
Rated current	16 A to 1600 A
Protection class	IP20
Mounting type	Fixed mounting
Number of poles	1, 2, 3, 4
Trip unit type	Thermal-magnetic or electronic
Protection functions	Overload, short-circuit
Ambient temperature	-25°C to +60°C