Siemens 3RT2026-1AP00 — 25 A Power Contactor Buying Guide

By Abdullah Zahid
12 min read
Siemens 3RT2026-1AP00 SIRIUS 3-pole power contactor 25A 11kW 230V AC coil for motor starter panel

Siemens 3RT2026-1AP00 SIRIUS Power Contactor, AC-3e/AC-3, 25 A, 11 kW / 400 V, 3-pole — Specifications, Pricing, and Selection Guide

When a controls engineer is finalizing a motor starter BOM for an 11 kW three-phase load, one part number comes up repeatedly in the SIRIUS family: the Siemens 3RT2026-1AP00. This is a 3-pole electromechanical power contactor rated 25 A AC-3 at 400 V, controlled by a 230 V AC coil, and housed in the compact S0 size format. If your panel runs on a 230 V AC control supply and your motor sits at or below 11 kW at 400 V, the selection decision is straightforward — but there are enough common ordering mistakes to justify a close look before committing budget.

If you have already confirmed this is the right part, check current pricing and availability for the Siemens 3RT2026-1AP00 at LeadTime.ca — ships worldwide.

Who Should Buy the Siemens 3RT2026-1AP00 — and Who Shouldn't

The Siemens 3RT2026-1AP00 is the right contactor for engineers and procurement specialists whose application meets all of the following criteria:

  • Motor rated current does not exceed 25 A under AC-3 continuous duty (11 kW at 400 V, 18 A at 500 V, or 13 A at 690 V)
  • 230 V AC control supply is available at the control station — this is the standard coil voltage for this SKU
  • Standard auxiliary contact configuration of 1 NO + 1 NC is sufficient for interlocking and status feedback
  • Panel layout includes DIN rail (TH35) with at least 45 mm of horizontal space for the S0 form factor
  • Installation environment falls within the -25°C to +60°C operating temperature range
  • Insulation voltage of 690 V covers the target network (400 V or 690 V three-phase)

If your motor exceeds 11 kW at 400 V, you need the 3RT2036-1AP00 rated at 18.5 kW. If your control supply is 24 V DC rather than 230 V AC, a different coil variant is required. If you need more than 1 NO + 1 NC auxiliary contacts natively, consider the 3RT2045 series or add a 3RT2000-2FC34 auxiliary block.

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What the Siemens 3RT2026-1AP00 Actually Does in a Motor Circuit

The Siemens 3RT2026-1AP00 is a 3-pole electromechanical power contactor — the primary switching device that connects and disconnects three-phase electrical power to a motor or load under remote control. When 230 V AC is applied across the A1 and A2 coil terminals, the electromagnetic coil pulls in the main contacts, completing the power circuit across L1-L2-L3 to T1-T2-T3. Remove the control voltage and the spring-loaded contacts open, isolating the motor. The entire switching action is mechanical and predictable, with no logic or firmware to manage.

Under AC-3 continuous duty, the 3RT2026-1AP00 is rated for 25 A at 400 V, translating to 11 kW of motor power — a common threshold for pump motors, conveyor drives, fan motors, and machine tool spindles in mid-size industrial panels. The built-in 1 NO + 1 NC auxiliary contact block handles interlocking and PLC status feedback without requiring a separate relay. At S0 size, the unit occupies a 45 mm footprint on a TH35 DIN rail, making it one of the more space-efficient options in this current class.

Typical System Architecture for the 3RT2026-1AP00

The 3RT2026-1AP00 sits at the main load switching point in the motor starter circuit, directly between the upstream protective device and the motor terminals. In a standard motor starter panel, the signal and power chain looks like this:

  • Upstream: three-phase supply bus → circuit breaker or motor protective circuit breaker providing short-circuit protection
  • Control layer: PLC digital output or pushbutton station → 230 V AC control circuit → A1/A2 coil terminals on the 3RT2026-1AP00
  • Main power path: L1, L2, L3 input terminals on the contactor → T1, T2, T3 output terminals → downstream to thermal overload relay
  • Thermal overload relay (e.g., 3UA51 series) → motor terminals for overload protection and trip signal back to control circuit
  • Auxiliary contacts (1 NO + 1 NC) → PLC input card or interlocking circuit for run confirmation and fault interlock

Where the 3RT2026-1AP00 Gets Installed: Industries and Use Cases

The 3RT2026-1AP00 is a genuine workhorse in mid-size motor starter panels across discrete manufacturing. Automotive assembly lines, food and beverage conveyor systems, and packaging machinery all regularly standardize on the SIRIUS 3RT20 series for their 7.5 kW to 11 kW motor circuits, precisely because spare part consistency reduces unplanned downtime risk across a plant with dozens of identical starter panels.

In water and wastewater treatment facilities, the 3RT2026-1AP00 is used for remote on/off control of pump motors across multiple geographically distributed sites. The 230 V AC control voltage integrates cleanly with site-wide control panels, and the 690 V insulation rating ensures a single SKU covers both 400 V and 690 V network installations without requiring a different part number per site.

HVAC and building automation applications frequently use this contactor for fan motor and air handling unit control, where AC-3 continuous duty, compact S0 size, and reliable auxiliary contact feedback all align well with the application requirements. In machine tool applications — bench-top lathes, milling machines, grinding units — the S0 footprint is particularly valued because panel space inside the machine cabinet is limited.

Dual-contactor reversing starters for forward/reverse motor control are another common deployment, where the 1 NO + 1 NC auxiliary contact configuration provides the mechanical safety interlock signal that prevents simultaneous energization of both contactors.

Application Typical Deployment
Motor starter cabinet — continuous duty 11 kW three-phase induction motor, 400 V AC, AC-3 duty, DIN rail panel
Water treatment pump station Remote pump motor control across multiple sites; standardized SIRIUS spares
HVAC fan motor control Air handling unit fan switching, 230 V AC control, auxiliary contact for BMS feedback
Reversing starter (forward/reverse) Dual 3RT2026-1AP00 with NC auxiliary cross-interlock for mechanical safety
Machine tool spindle motor Compact panel in lathe or milling machine; S0 size critical for enclosure fit
Soft-starter bypass contactor Upstream bypass of soft-starter after ramp-up; reduced switching cycles extend contact life

Purchase-Critical Specifications for the Siemens 3RT2026-1AP00

Parameter Value
Rated current AC-3 25 A at 400 V / 18 A at 500 V / 13 A at 690 V
Rated current AC-1 (resistive) 40 A at 400 V and 690 V
Rated current AC-4 (intermittent) 15.5 A at 400 V
Motor power rating AC-3 11 kW at 400 V / 11 kW at 500 V / 11 kW at 690 V
Insulation voltage 690 V
Control voltage (coil) 230 V AC, 50 Hz
Auxiliary contacts 1 NO + 1 NC, rated 10 A
Size category / mounting S0 / DIN rail TH35
Operating temperature -25°C to +60°C
Mechanical life (AC-4) More than 200,000 operating cycles

Full technical specifications are available on the product page at LeadTime.ca.

3RT2026-1AP00 vs. 3RT2025-1AP00 vs. 3RT2036-1AP00: Which One Do You Actually Need?

Model Rated Current AC-3 Power at 400 V Control Voltage Auxiliary Contacts Size
3RT2025-1AP00 16 A 7.5 kW 230 V AC 1 NO + 1 NC S0
3RT2026-1AP00 (this model) 25 A 11 kW 230 V AC 1 NO + 1 NC S0
3RT2036-1AP00 40 A 18.5 kW 230 V AC 1 NO + 1 NC S2

The 3RT2025-1AP00 is the right call if your motor is 7.5 kW or below and cost is the primary constraint — it shares the same S0 footprint and 230 V AC control supply. Step up to the 3RT2036-1AP00 if your motor exceeds 11 kW at 400 V or if your AC-4 intermittent duty current exceeds the 15.5 A AC-4 rating of the 3RT2026-1AP00. For applications requiring 24 V DC control, a different coil variant is required entirely — do not assume coil substitution is field-swappable without confirming part compatibility. If your architecture uses 230 V AC control and an 11 kW motor at 400 V, the 3RT2026-1AP00 is the correct choice — check current availability at LeadTime.ca.

Expert Verdict: Honest Assessment of the Siemens 3RT2026-1AP00

The 3RT2026-1AP00 earns its position as one of the most commonly specified contactors in the 11 kW motor class for good reason. The S0 form factor keeps panel layouts tight, the 690 V insulation rating eliminates the need for different SKUs across 400 V and 690 V plant networks, and the SIRIUS product family's global installed base means spare parts planning is genuinely straightforward. With more than 200,000 operating cycles rated under AC-4 duty and an operating temperature envelope of -25°C to +60°C, this contactor handles both heated and unheated cabinet environments without derating concerns below 40°C ambient.

Where the 3RT2026-1AP00 has real limits: the 15.5 A AC-4 intermittent duty rating catches engineers off guard when specifying for compressors or applications with frequent short-duration starts. If your motor draws more than 15.5 A and your duty cycle is AC-4, this contactor is undersized for that service — step to the 3RT2036-1AP00 without compromise. Similarly, the 230 V AC coil is non-negotiable with this SKU; if your control panel runs entirely on 24 V DC, ordering this model creates a wiring problem that cannot be resolved without a transformer or a different part number. And if you need more than 1 NO + 1 NC auxiliary contacts integrated, you will need to either add a 3RT2000-2FC34 auxiliary block or move to a larger series.

From a procurement standpoint, the 3RT2026-1AP00 is a commodity item in the SIRIUS line — widely stocked, with standard lead times of one to two weeks from distributor inventory and two to four weeks on direct Siemens orders. Volume pricing typically improves at 50 or more units. If this matches your system requirements, view current stock and pricing for the 3RT2026-1AP00 at LeadTime.ca.

For volume pricing or to confirm lead time before committing to a build, contact the LeadTime.ca team directly — we ship worldwide.

Wiring and Installation Overview for the 3RT2026-1AP00

  • Main circuit terminals L1, L2, L3 (input) and T1, T2, T3 (motor output) accept up to 10 mm² wire for full AC-1 rated current; use M4 screw terminals torqued to the specified value for your wire gauge
  • Control coil connects to A1 and A2 terminals with 230 V AC supply; control circuit wiring minimum 1.5 mm² is typical; verify 230 V AC is present at these terminals before troubleshooting pickup failures
  • DIN rail mounting requires TH35 (35 x 7.5 mm) rail; the S0 size contactor occupies a 45 mm horizontal slot; confirm panel layout before ordering
  • Auxiliary NO and NC contacts are wired directly to PLC input cards or interlocking circuits; auxiliary contacts are rated 10 A maximum — do not route motor-level current through these terminals
  • Apply lock-out/tag-out (LOTO) before installation; verify contactor is fully seated on DIN rail and main circuit terminals are torqued before energizing the control circuit for the first time

Compatible Accessories and System Expansion

The Siemens 3RT2026-1AP00 is designed to work within the broader SIRIUS 3RT20 ecosystem. The following accessories and companion components are directly compatible and commonly ordered alongside this contactor:

  • 3RT2000-2FC34 — Add-on auxiliary contact block providing 4 NO + 4 NC contacts for multi-machine interlocking applications requiring more than the standard 1 NO + 1 NC
  • 3UA51-00-1A — Thermal overload relay companion for 3 A to 12 A motor protection range, mounts directly downstream
  • 3UA51-00-1C — Thermal overload relay companion for 9 A to 40 A motor protection range, covering the full AC-3 current band of the 3RT2026-1AP00
  • 3RT2026-1A64 — 230 V AC coil replacement assembly; direct plug-in replacement for coil burn-out scenarios, no soldering required

Wrong-Part Prevention Checklist Before You Order the 3RT2026-1AP00

Before placing an order, run through this checklist to avoid mismatches that cause project delays and unplanned panel redesign:

  1. Confirm motor rated current does not exceed 25 A for AC-3 duty (or 40 A for AC-1 no-load switching)
  2. Verify control voltage is 230 V AC available on site; do not assume 24 V (different model required)
  3. Check motor starting current (inrush) does not exceed mechanical performance limits for your voltage class
  4. Confirm required auxiliary contact ratio is 1 NO + 1 NC (standard); multi-contact variants exist
  5. Ensure DIN rail mounting space is available (S0 size is compact; verify panel layout)
  6. Validate operating temperature range -25 to +60°C matches installation environment (heated/unheated cabinets)
  7. Check that screw terminal torque and wire gauge are compatible with your installation practices
  8. Verify insulation voltage 690 V is sufficient (does not mix 400 V and 690 V panels on same contactor)

If every item above checks out, confirm availability and request a quote for the Siemens 3RT2026-1AP00 at LeadTime.ca.

Frequently Asked Questions

Can the 3RT2026-1AP00 be used for a 7.5 kW motor at 400 V?

Yes. The contactor is oversized for a 7.5 kW load at 400 V, which draws approximately 13.6 A — well within the 25 A AC-3 rating. Running below rated current reduces contact wear and extends mechanical life. There is no performance penalty for using a higher-rated contactor on a smaller motor.

What happens if I apply 24 V DC to the A1/A2 coil terminals of the 3RT2026-1AP00?

The coil on the 3RT2026-1AP00 is rated for 230 V AC. Applying 24 V DC will not energize the coil and the contactor will not pick up. If your control supply is 24 V DC, you need a different coil variant — confirm the correct catalog number before ordering. Do not assume coils are field-interchangeable without verifying part compatibility.

What is the difference between AC-3 and AC-4 duty, and which applies to my pump application?

AC-3 covers continuous motor duty where the motor runs for extended periods between start and stop cycles — the typical mode for pumps, fans, and compressors running 20 or more minutes per cycle. AC-4 covers intermittent duty with frequent short-duration starts and stops, which puts significantly more stress on contacts. For AC-4, the 3RT2026-1AP00 is derated to 15.5 A at 400 V. If your pump starts and stops more than a few times per hour with short run periods, calculate the actual AC-4 current demand before confirming this model.

How many auxiliary contacts does the 3RT2026-1AP00 include, and can I add more?

The standard 3RT2026-1AP00 includes 1 NO and 1 NC auxiliary contact, both rated at 10 A. If your interlocking logic requires additional auxiliary contacts, the 3RT2000-2FC34 add-on block provides 4 NO + 4 NC and is compatible with this contactor. Do not attempt to use the main power contacts as auxiliary contacts — they are not rated or wired for control-level switching duty.

Is the 3RT2026-1AP00 RoHS compliant and suitable for North American installation?

The 3RT2026-1AP00 is RoHS 2 compliant. UL and CSA certifications apply at the system integration level — confirm with your panel builder and authority having jurisdiction for the specific installation. LeadTime.ca ships this product worldwide, and global compliance documentation is available through the official Siemens SiePortal datasheet.

What is a realistic lead time for the 3RT2026-1AP00, and are volume discounts available?

Standard lead time from distributor inventory is one to two weeks; direct Siemens orders typically run two to four weeks. As a mature, widely stocked commodity item in the SIRIUS line, spot availability is generally good outside of peak Q3/Q4 demand periods. Volume discounts typically apply at 50 or more units with a reduction of roughly 10 to 15 percent. Contact the LeadTime.ca team directly for a volume pricing quote.

Why Order the Siemens 3RT2026-1AP00 from LeadTime.ca

  • Ships worldwide — LeadTime.ca sources and fulfills orders globally, not limited to any single region
  • Hard-to-find stock — SIRIUS parts including long-tail SKUs and accessories sourced from verified supply channels
  • Fast response — quote turnaround and availability confirmation without extended wait times
  • Volume pricing — competitive tiered pricing available for integrators and procurement teams ordering in quantity
  • Technical support at point of sale — confirm you have the right part before the order ships

At-a-Glance Summary: Siemens 3RT2026-1AP00

  • 3-pole power contactor, SIRIUS 3RT20 series, S0 size, 45 mm DIN rail footprint
  • AC-3 continuous motor duty: 25 A at 400 V, 18 A at 500 V, 13 A at 690 V
  • AC-4 intermittent duty rating: 15.5 A at 400 V — confirm this is not exceeded for frequent start-stop loads
  • Motor power: 11 kW at 400 V AC under AC-3 duty
  • Control coil: 230 V AC, 50 Hz — 24 V DC applications require a different variant
  • Auxiliary contacts: 1 NO + 1 NC, 10 A rated — expandable with 3RT2000-2FC34 add-on block
  • Insulation voltage: 690 V — covers both 400 V and 690 V three-phase networks
  • Operating temperature: -25°C to +60°C — no derating required below 40°C ambient
  • Mechanical life: more than 200,000 operating cycles at AC-4 duty
  • Standard lead time: 1 to 2 weeks from distributor stock; 2 to 4 weeks direct order
  • RoHS 2 compliant; available for worldwide shipment through LeadTime.ca