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Siemens 3RT20252AC20 S0 Contactors

All parts below share the same 3RT2025 base product number, 3PST-NO main contact form, 67VA coil power, 40ms operate time, box encapsulation, and chassis/DIN rail mounting. Differences are limited to coil voltage and auxiliary contact configuration.

Siemens 3RT20252AC20 S0 Contactors

Catalog comparison

All parts below share the same 3RT2025 base product number, 3PST-NO main contact form, 67VA coil power, 40ms operate time, box encapsulation, and chassis/DIN rail mounting. Differences are limited to coil voltage and auxiliary contact configuration.

MPNCoil VoltageMust Operate VoltageAuxiliary ContactsSimilarity
3RT20252AC2024VAC20.4 VAC1NO/1NC
3RT20252AC2424VAC20.4 VAC2NO/2NC1.00
3RT20252AB0024VAC19.2 VAC1NO/1NC0.96
3RT20252AG20110VAC93.5 VAC1NO/1NC0.96
3RT20252AM20208VAC176.8 VAC1NO/1NC0.96
3RT20252AN20220VAC187 VAC1NO/1NC0.96
3RT20252AN24220VAC187 VAC2NO/2NC0.96
3RT20252AL20230VAC195.5 VAC1NO/1NC0.96
3RT20252AL24230VAC195.5 VAC2NO/2NC0.96

These rows require the reader's own technical qualification; they are catalog peers, not OEM-approved substitutes.

Why the 24VAC variants appear most similar: The primary part and 3RT20252AC24 share identical coil voltage and must-operate voltage (20.4 VAC), differentiating only in auxiliary contact count (1NO/1NC versus 2NO/2NC). 3RT20252AB00 matches the auxiliary layout but specifies a slightly lower must-operate voltage of 19.2 VAC at the same nominal coil rating.

Why the higher-voltage variants are listed: The 110VAC through 230VAC parts share all other specs—same contact rating, operate time, mounting, and features—with coil voltage being the sole distinguishing parameter. Must-operate thresholds scale proportionally with nominal coil voltage.

Siemens 3RT20252AC20 parameters

  • Base product number: 3RT2025
  • Contact rating: 17 A (main contacts)
  • Contact form: 3PST-NO (3 Form A)
  • Coil voltage: 24VAC
  • Coil power: 67VA
  • Must operate voltage: 20.4 VAC
  • Operate time: 40 ms
  • Auxiliary contacts: 1NO/1NC
  • Mounting: Chassis mount, DIN rail
  • Operating temperature: 25°C to 60°C
  • Encapsulation: Box

Family context

The 3RT2025 series falls within Siemens' Size S0 frame contactor line. The part number suffix encodes coil voltage ("AC20" = 24VAC) and contact arrangement ("1" = one auxiliary contact block). This ordering logic is common across the S0 series; selecting within the family typically involves matching coil class to the available control voltage and choosing the auxiliary contact pattern required by the control scheme.

FAQ

What distinguishes 1NO/1NC from 2NO/2NC auxiliary configurations in the 3RT20252AC20 family? The 1NO/1NC variants provide one normally-open and one normally-closed auxiliary contact, suitable for basic status signaling or interlock paths. The 2NO/2NC variants double the auxiliary contact count, enabling more complex control circuits without adding external relays.

Can I substitute a 230VAC coil variant for the 24VAC 3RT20252AC20 in the same enclosure? No—coil voltage is a fixed parameter. A 230VAC coil will not energize reliably at 24VAC, and applying 230VAC to a 24VAC coil will cause damage. The reader must select the coil voltage matching the available control circuit.

What is the maximum switching current for the main contacts of 3RT20252AC20? The contact rating is listed as 17 A for the main contacts under the stated conditions.

Last updated: May 11, 2026