ABB PSTX Softstarters

• Controlled starting and stopping to suit the driven load and process.
• Built-in bypass operation after starting; upstream short-circuit protection still requires coordination.
• Motor protection, diagnostics and control settings to be checked against the exact unit’s manual.
• Graphical display, detachable keypad and built-in Modbus RTU described by ABB; other protocols require the applicable interface or option.

Motor Duty & Connection Arrangement

Select using motor nameplate current and voltage, load characteristics, acceleration time, stopping requirements, starts per hour and ambient conditions. ABB lists normal-start and heavy-duty ratings separately. The type designation alone does not establish the permissible motor loading for every duty.

ABB provides different selection data for in-line and inside-delta connections. Inside-delta use requires the correct motor winding leads, connection diagram and protection arrangement. Do not use an inside-delta current value as an in-line rating. Confirm the exact model and installation instructions before selecting a configuration.

Supply, Protection & Version Boundaries

Check main-circuit voltage separately from control supply. The retained table contains -600-70 model designations; do not apply the maximum voltage of ABB’s wider PSTX range to every entry. Use the selected code’s data sheet and matching regional documentation.

Confirm overload settings, trip class, available protection inputs, contactor or disconnecting requirements and upstream fuse/circuit-breaker coordination. Built-in bypass and electronic protection do not remove the need to check the complete starter circuit. Communication interfaces, options and firmware must match the installed unit.

Use the applicable IEC/EN 60947-4-2 data and regional approvals. North American hp/FLA and short-circuit combination ratings must be read under their own conditions rather than copied from an IEC selection table. Historical ratings, certification and replacement suitability require the original code and documentation.

Choosing a PSTX Model & Requesting a Quote

Send the complete product model, ABB Order Code / Article Number, quantity and destination country. Include motor nameplate current/voltage, load type, starting duty, main and control supplies, connection arrangement, protection and communication requirements. For an existing unit, provide nameplate and wiring photos, hardware/firmware identification and required options.

Request a quote through Contact. Related pages: PSE and PSR / PSRC. Their functions and application ranges are separate; similar names do not establish interchangeability.

Technical references: ABB PSTX overview, ABB softstarter catalogue and the existing comprehensive catalogue below.