Siemens 3RT20241AN24 Contactors

Overview

The Siemens 3RT20241AN24 is a size S00 electromechanical contactor in the 3RT2 series, delivering a 12 A three-pole main switching structure with a 220 VAC coil and two integrated auxiliary contacts (2NO + 2NC). The MPN prefix 3RT2024 places this firmly in Siemens' standard industrial contactor family (3RT2 / Sirius) intended for motor and load control in AC-1 and AC-3 applications; the AN suffix encodes the contact arrangement and voltage class ("N" = 220 VAC 50/60 Hz), and 24 is the size/style digit. The title states "S0" (S00), which aligns with the compact 45 mm width rail-mount form factor typical of that size class, though exact mechanical dimensions are not provided in the catalog fields. Key catalog-derived parameters are summarized below.

Key Parameters

⚠ Verification required: Electrical ratings critical for branch protection coordination — AC-1 current, AC-3 horse-power rating, making/breaking capacity, dielectric withstand, and contact wear ratings — are not present in the supplied fields. Selection must not proceed on electrical ratings until verified against the official Siemens Sirius 3RT2 datasheet.

Integration / Installation Notes

The 3RT20241AN24 is a DIN-rail-mountable contactor intended for motor branch and general-load switching in industrial enclosures.

• Terminal style and wire size are not listed in the catalog fields; these must come from the datasheet.
• IP rating / enclosure requirements are not stated; installation in a suitable enclosure is implied but not specified.
• ** DIN rail compatibility** (TH35-7.5 or TH35-15) is consistent with standard Sirius practice, but physical cutout/flange dimensions should be confirmed.
• Auxiliary contact block is integral; no separate add-on block is specified as needed for the 2NO/2NC configuration.

The catalog data does not specify: torque settings, maximum switching voltage, Electrical Life (cycles), Mechanical Life (cycles), or coil inrush vs seal power separately.

Selection / Substitution Guidance

Substitution of the 3RT20241AN24 with any listed alternate requires datasheet-level validation across the following dimensions:

1. Coil voltage — must match the control system exactly; coil mismatch will cause failure to pull in or coil burnout.
2. Auxiliary contact count and type — the seed specifies 2NO/2NC; alternates with 1NO/1NC (3RT20241AN20, 3RT20241AL20) cannot substitute in circuits requiring both normal-open and normal-closed auxiliary signals.
3. Must-operate voltage — differs between coil voltage classes; selecting a lower-voltage coil variant (24 VAC, 110 VAC) for a 220 VAC circuit will result in non-operation.
4. Operating temperature — the catalog states 25°C to 60°C; full datasheet may allow -25°C to +60°C for industrial use; cold-environment applications require confirmation.
5. Mechanical envelope — all listed parts share base number 3RT2024 and should have the same foot print, but packaging (Box vs Bulk) does not affect fit.

Similar Catalog Parts

Why they are similar: All nine parts share base number 3RT2024, 12 A contact rating, 3PST-NO main pole structure, auxiliary contact feature, and DIN-rail/chassis mounting. They differ primarily in coil voltage class and auxiliary contact count, which are the primary selection differentiators within the Sirius S00 family.

• 3RT20241AN20 — Same coil voltage and must-operate as the seed; identical in all listed parameters except auxiliary contacts reduced to 1NO/1NC and operate time 38 ms vs 40 ms. Valid substitute only for circuits not requiring the second set of auxiliary contacts.
• 3RT20241AN60 — Same mechanical and contact spec; coil voltage class 200 VAC (must-operate not listed in catalog). Verify must-operate is compatible with the control circuit before use.
• 3RT20241AL24 — 230 VAC coil with must-operate 195.5 VAC; auxiliary contacts reduced to 1NO/1NC; cannot substitute where 2NC is required for protection wiring.
• 3RT20241AC24 — 24 VAC coil class (must-operate 20.4 VAC); maintains 2NO/2NC auxiliary config. Not interchangeable with 220 VAC coil without control power change.
• 3RT20241AG24 / AK64 / AF04 — 110 VAC and 120 VAC coil variants; all retain 2NO/2NC auxiliary config except AF04. Cannot substitute on a 220 VAC control circuit without coil replacement or control power conversion.

FAQ

Q: What is the difference between the 3RT20241AN24 and the 3RT20241AN20? A: Both are 220 VAC coil contactors with identical main pole ratings (12 A, 3PST-NO). The seed (3RT20241AN24) provides 2NO/2NC auxiliary contacts, while the 3RT20241AN20 provides only 1NO/1NC. If the application relies on two auxiliary contacts in a specific configuration, the AN24 is required; otherwise the AN20 may be substituted after verifying wiring compatibility.

Q: Can a 230 VAC coil contactor such as the 3RT20241AL24 substitute for the 3RT20241AN24 on a 220 VAC control system? A: No. The 3RT20241AL24 requires 230 VAC nominal with a must-operate voltage of 195.5 VAC. A nominal 220 VAC control system (220–240 V range depending on supply tolerance) may not reliably pull in the 230 VAC coil. Coil voltage must match the control circuit; do not substitute across voltage classes without evaluating control supply tolerance.

Q: Are the main pole current ratings of the 3RT20241AN24 sufficient for motor starting (AC-3)? A: The catalog lists a contact rating of 12 A but does not specify whether this is AC-1 (non-inductive), AC-3 (motor starting), or another utilization category. AC-3 rating at a given voltage is typically lower than AC-1. Before specifying for motor starting duty, confirm the AC-3 HP/kW rating and making/breaking currents from the Siemens Sirius 3RT2 datasheet.