Digistart D2 (CS) / D3 (IS) — soft starters for induction motors 18–1 600 A, up to 690 V

Country: Poland · Model: Digistart D2 / D3

Digistart D2 (CS) and D3 (IS) are soft starters for three-phase induction motors for currents of 18–1 600 A and mains up to 690 V. They raise the motor voltage smoothly during starting and lower it during stopping, so they limit starting currents and mechanical shocks, above all in pumping systems.

Digistart D2 (CS): 18–200 A; 3×200–440 V or up to 575 V AC; built-in bypass contactor; setup with rotary switches
Digistart D3 (IS): 23–1 600 A; 3×200–440 V or 3×380–600 (690) V AC; version with built-in bypass contactor
Auxiliary supply: 110–440 V AC
D3 power circuit: fully controlled, 2 thyristors in each phase; inside-delta connection

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Technical specifications

Digistart D2 (CS)	18–200 A; 3×200–440 V or up to 575 V AC; built-in bypass contactor; setup with rotary switches
Digistart D3 (IS)	23–1 600 A; 3×200–440 V or 3×380–600 (690) V AC; version with built-in bypass contactor
Auxiliary supply	110–440 V AC
D3 power circuit	fully controlled, 2 thyristors in each phase; inside-delta connection
Protection	stalled start, motor overload, imbalance, mains frequency, phase sequence, contactor overload; D3: RTD/PT100 (6 sensors) and earth fault
Communication	Modbus RTU, DeviceNet, PROFIBUS, EtherNet/IP, PROFINET, USB (modules)
Options	remote keypad, input-output boards, ultra-fast fuse kits, IP20/IP22 terminal covers, DSSoft software (up to 99 devices)

Specifications are taken from the manufacturer’s technical documentation. Updated 11/09/2026.

Description

The D2 (formerly CS) is an economical series for 18–200 A for 3×200–440 V or up to 575 V AC mains with 110–440 V AC auxiliary supply. The bypass contactor is built in, setup is done with rotary switches, and diagnostics with LEDs. The D3 (formerly IS) covers 23–1 600 A, although the page heading states from 18 A, and works in 3×200–440 V and 3×380–600 (690) V AC mains. Its power section is fully controlled with two thyristors in each phase, the current of each phase is monitored even after switching to bypass, and the motor can be connected inside the delta. The optional expansion board has 2 digital inputs, 3 relay outputs, an analog input and output, and the 6-channel RTD/PT100 sensor board also monitors earth faults through an external 1000:1, 5 VA current transformer. Modbus, DeviceNet, Ethernet, PROFIBUS, PROFINET and USB modules add communication, and the DSSoft program networks up to 99 soft starters.

How to choose

The boundary between the series is the current. Up to 200 A the D2 is enough, and above 200 A up to 1 600 A the D3 is needed, with a graphic display for programming starting, braking and protections. The D2 remote keypad shows motor current and temperature and has a 4–20 mA analog output, and for the 140–200 A models there are IP22 terminal covers. If winding temperature sensors or earth fault monitoring are needed, choose the D3.

Request a price and lead time

Digistart D2 (CS) / D3 (IS) — soft starters for induction motors 18–1 600 A, up to 690 V. We reply within one business day.

Or email office@usk.ua or call +38 (044) 339-50-20.

FAQ

What currents are Digistart D2 and D3 made for?

The D2 is rated for 18–200 A, the D3 for 23–1 600 A. The page heading for the D3 states a range from 18 A.

What mains does Digistart D3 work in?

In 3×200–440 V and 3×380–600 (690) V AC mains, while the D2 is rated for 3×200–440 V or up to 575 V AC.

What motor protections does Digistart have?

Protection against stalled start, motor overload, load imbalance, mains frequency error, wrong phase sequence and contactor overload. The D3 additionally has 6-channel RTD/PT100 sensors and earth fault monitoring.

How many soft starters does the DSSoft program network?

Up to 99 soft starters in one network.

Is there a built-in bypass contactor?

In the D2 the bypass contactor is built in as standard, and the D3 is also made in a version with a built-in bypass contactor.