Product Overview

The ABB PSTB370-600-70 is a high-performance soft starter for industrial motors.
It controls acceleration and deceleration to reduce mechanical stress.
This model handles a main circuit voltage from 208 to 600 V AC.
The control supply voltage ranges from 100 to 250 V AC at 50/60 Hz.
You can use this PSTB370-600-70 for both in-line and inside delta connections.

Technical Specifications

The ABB PSTB370-600-70 delivers a rated operational current of 370 A.
For in-line connection, the rated power is 200 kW at 400 V.
It achieves 257 kW at 500 V with the same connection type.
Inside delta connection increases the current to 640 A.
The power then reaches 355 kW at 400 V and 450 kW at 500 V.

This soft starter has a service factor of 115% .
It includes a built-in electronic overload protection system.
The starting capacity reaches 3x Ie for 15 seconds.
You can set the ramp time from 0 to 120 seconds.
Initial voltage during start adjusts from 30% to 70%.
The current limit function ranges from 1.5 to 7x Ie.

The device offers several signal relays for status feedback.
These include a run signal relay, a by-pass relay, and a fault relay.
An overload signal relay provides additional monitoring.
The analog output supports 0-10 V, 0-20 mA, or 4-20 mA.
Three LED indicators show ready (green), protection (yellow), and fault (red).
The PSTB370-600-70 can perform 10 starts per hour at 3.5x Ie for 7 seconds.

Environmental Data

The ambient air temperature for operation is 0 to +50 °C.
Storage temperature ranges from -25 to +70 °C.
This unit has a protection degree of IP00 for main terminals.
It complies with IEC 60529 and EN 60529 standards.

Connection Details

Main circuit terminals use bars with a 10.5 mm hole diameter.
The bar dimensions are 25 mm width and 6 mm thickness.
Control circuit connections accept rigid wires up to 2.5 mm².
Supply circuit connections also accept 2.5 mm² rigid wires.
Tightening torque for the main circuit is 35 N·m.
Control and supply circuits require only 0.5 N·m.

Dimensions and Weight

The product net width measures 366 mm.
Net height is 460 mm and net depth is 361 mm.
Product net weight equals 31 kg.
Package gross weight reaches 40 kg for shipping.

Installation Guidelines

Mount the ABB PSTB370-600-70 in a vertical position.
Ensure at least 100 mm free space above and below the unit.
Do not block the ventilation openings during operation.
Use copper cables only for main circuit connections.
Tighten main terminals to exactly 35 N·m to avoid overheating.
Connect the control wires with a torque of 0.5 N·m.
Separate control wiring from power cables to reduce noise.
Verify the supply voltage matches 100-250 V AC before powering on.
Set the motor full load current correctly on the dial.
Perform a dry run without load to test ramp parameters.

Package Contents

• 1 x ABB PSTB370-600-70 soft starter unit

• 1 x Control terminal connector block

• 1 x Product quick start guide

• 1 x Mounting screws set

• 1 x Bus bar connection kit

Frequently Asked Questions (FAQ)

1. Can the ABB PSTB370-600-70 work with a 500V AC supply?

Yes, the PSTB370-600-70 operates perfectly at 500V AC. It delivers 257 kW in-line and 450 kW inside delta.

2. Does this soft starter need an external bypass contactor?

No, the ABB PSTB370-600-70 includes a built-in bypass signal relay. This reduces heat and increases reliability.

3. What happens if the ambient temperature exceeds 50°C?

Operation above 50°C requires current derating. Contact ABB technical support for precise derating curves.

4. Can I use analog output to monitor motor current?

Yes, the analog output provides 0-10V or 4-20mA signals. You can scale these to represent motor current.

5. How do I clear a fault on the PSTB370-600-70?

Press the reset button on the front panel. You can also cycle the control supply voltage off and on.