5SY7340-7

What type of circuit breaker is this?

This is a SENTRON miniature circuit breaker designed for industrial and mechanical engineering applications. It is a 3-pole device with a C tripping characteristic, making it suitable for circuits where moderate inrush currents may be expected.

What are the main electrical ratings?

The unit is rated at 40 A and 400 V AC with a frequency range of 50/60 Hz. It also has a maximum rated operating voltage of 72 V DC. For AC applications, the Siemens 5SY7340-7 is intended for dependable branch circuit protection in compact panel layouts.

What breaking capacity does it offer?

The breaker provides a rated short-circuit breaking capacity of 15 kA according to EN 60898 and 20 kA according to IEC 60947-2. For DC applications, it is rated at 15 kA according to IEC 60947-2.

How many poles does it have?

It is a 3-pole breaker, suitable for three-phase systems where all three phases need coordinated protection within one device.

What does the C tripping characteristic mean?

A C curve breaker is typically chosen for circuits with moderate inrush current, such as many general industrial loads. It offers a balance between avoiding nuisance tripping and providing effective overcurrent protection.

What size is the device?

The breaker measures 90 mm high, 54 mm wide and 76 mm deep, with an installation depth of 70 mm. It occupies 3 modular width units, which helps when planning space inside a distribution board or control cabinet.

How is it mounted?

This model uses a quick assembly mounting system and can be installed in any mounting position. That gives added flexibility when integrating it into different panel designs.

What cable sizes can be connected?

It accepts solid and stranded conductors from 0.75 mm² to 35 mm², and finely stranded conductors with end treatment from 0.75 mm² to 25 mm². The terminal range is also given as AWG 18 to AWG 4.

What tightening torque should be used on the terminals?

The specified tightening torque for the screw terminals is 2.5 to 3.5 Nm, which is equivalent to 22 to 31 lbf·in.

Does it include touch protection?

Yes. The breaker includes touch protection and is rated IP20 when conductors are connected.

Can supplementary accessories be added?

Yes. The device is designed to accept installable supplementary devices, which can be useful when configuring a panel for specific operational requirements.

Does it switch the neutral conductor?

No. This is not a neutral-switching model, so it is intended for phase protection rather than switching a neutral pole.

Is it suitable for use as a main switch in machinery panels?

It has properties for main switches in accordance with EN 60204-1, which can be helpful in machinery and industrial control applications where that feature is required.

What environmental conditions can it handle?

The breaker is specified for operation from -40 °C to 70 °C and for storage from -40 °C to 75 °C. This makes it a practical choice for a wide range of industrial environments.

Are there any notable material or design features?

Yes. This model is halogen-free, silicon-free and sealable. It also features combined top and bottom terminals, which can simplify installation depending on the panel arrangement.

What is the typical mechanical service life?

The typical mechanical service life is 10,000 operating cycles, reflecting a design intended for repeated operation in demanding industrial settings.