3RW4036-1BB05

What does this soft starter do?

This unit is designed to reduce the electrical and mechanical stress that can occur when a three-phase motor starts. By controlling the starting voltage, it helps deliver a smoother ramp-up than direct-on-line starting and is suited to standard motor starting applications.

What supply voltage range is it intended for on the power circuit?

It is intended for standard-circuit operation on 400 to 600 V AC systems at 50/60 Hz. This makes it suitable for higher-voltage three-phase motor applications within that range.

What is the rated current of the unit?

The rated operational current is 45 A at 40°C. The rating reduces with temperature to 42 A at 50°C and 39 A at 60°C, so panel temperature should be considered during selection.

What motor power is it suitable for?

The unit is rated for up to 22 kW at 400 V and up to 30 kW at 500 V under standard switching conditions at 40°C. It is also listed at 30 hp for 460/480 V and 40 hp for 575/600 V at 50°C.

What control voltage does it require?

It uses a 24 V AC/DC control supply. That gives flexibility where the control circuit is already standardised around 24 V control power.

Does it include an internal bypass function?

Yes. The unit includes an integrated bypass contact system. This helps reduce heat generation in operation once the motor has reached running speed.

Does it provide motor overload protection?

Yes. It includes motor overload protection as part of the device functions. It also supports adjustable current limitation and external reset, but it does not provide thermistor motor protection evaluation.

Can it be used in an inside-delta configuration?

No. This model is not designed for inside-delta operation. It is intended for standard circuit connection.

What size is the unit?

This is an S2 frame soft starter. Its approximate dimensions are 55 mm wide, 160 mm high and 170 mm deep, which can be useful when checking panel space before installation.

How is the unit mounted?

It is designed for screw mounting and snap-on mounting. The datasheet also specifies mounting position guidance, so installation orientation and surrounding space should be checked during panel layout.

What terminal style does it use?

The main, auxiliary and control connections use screw terminals. That makes the unit suitable for applications where secure fixed wiring is preferred.

What auxiliary signalling contacts are available?

The device provides signalling contacts for status indication, including ON/RUN, BYPASSED and FAILURE/OVERLOAD functions. In the datasheet, this is shown as 2 NO auxiliary contacts and 1 changeover contact.

What conductor sizes can be connected?

For the main circuit, the unit accepts a broad range of conductor sizes depending on conductor type and clamping point, including solid, stranded and finely stranded conductors. For auxiliary contacts, it accepts solid conductors from 0.5 to 2.5 mm² and finely stranded conductors with end treatment from 0.5 to 1.5 mm².

What ambient temperature range is it designed for?

It is designed for operation from -25°C to +60°C, with storage from -40°C to +80°C. Derating starts above 40°C, so the current and application conditions should be reviewed for warmer environments.

What protection level does the front of the unit offer?

The front of the unit is rated IP20 and is described as finger-safe from the front when properly installed. In practice, this means the device is intended for installation inside a suitable control panel or enclosure.

Is this model suitable for long motor cable runs?

The datasheet gives a maximum cable length of 300 m. Actual application performance can still depend on the wider motor circuit design, but that figure is a useful reference point when assessing suitability.

Is there a minimum motor load requirement?

Yes. The minimum load is specified as 20% of the device rated motor current. This is worth checking where the motor load is especially light or variable.

Why might this unit be chosen for a panel with limited space?

The combination of a compact S2 frame, integrated bypass contact system, 24 V AC/DC control supply and built-in overload capability makes 3RW4036-1BB05 a practical choice for many standard motor starting duties where space and straightforward wiring matter.