Siemens Sentron Undervoltage Release for use with 3VA1 Series Circuit Breaker

The auxiliary and alarm switches for 3VA molded case circuit breakers can be installed in all sizes of all breakers up to 630 A.
All auxiliary and alarm switches are designed as changeover contacts and therefore provide a high degree of flexibility for planning and installation purposes

Auxiliary switches signal the position of the main contacts of the molded case circuit breaker (RS 874-4534 and 874-4537)
Trip alarm switches signal every circuit breaker trip, regardless of the cause of the trip (RS 874-4512 and 874-4515)
Electrical alarm switches are operated as soon as the main contacts of the molded case circuit breaker open in the event that the breaker is tripped by the ETU (RS 874-4519)
Short circuit alarm switches signal trips only if they have been initiated by a short circuit (RS 874-4528)

Undervoltage releases trip the molded case circuit breaker in the event that the rated voltage fails or drops to between 70 % and 35 % of its normal value (in compliance with the relevant standard)
The units are available with rated voltages in the following range:

230 VAC (RS 874-4525)
24 VDC (RS 874-4521)

Shunt trips of type STL can be fitted in the left-hand accessories compartment as an alternative to an undervoltage release. The units are available with five rated voltages in the following range:

230 VAC (RS 874-4540)
24 VAC/VDC (RS 874-4531)

This undervoltage release is a crucial accessory for Siemens Sentron circuit breakers, enhancing electrical protection by ensuring effective operation in low voltage conditions. It is compatible with various 3VA1 series circuit breakers, which helps to protect electrical systems from potential damage caused by undervoltage events.

• Compact dimensions allow for efficient integration in electrical systems
• Overvoltage category III ensures improved safety
• Helps to prevent equipment damage as a result of low voltage
• Lightweight design facilitates easy installation and handling

• Utilised with 3VA1 100/160 circuit breakers for enhanced protection
• Suitable for systems needing reliable undervoltage relay functionality

It prevents the circuit breaker from operating in low voltage situations, ensuring safety and mitigating equipment damage.

Regular inspections for wear and functionality are advisable to ensure ongoing reliability.

It is specifically designed for 24 V DC applications and should not be used outside this parameter.

Siemens 3VA MCCBs and accessories