The Siemens 3RT2045-1AF00 is a SIRIUS 3RT2 power contactor in size S3 that switches three-phase motors up to 37 kW at 400 V (80 A in utilisation category AC-3), with a 110 V AC, 50 Hz operating coil. It has 1 NO + 1 NC integrated auxiliary contacts, and Siemens rates it at 125 A for resistive (AC-1) loads at 40 °C. Per the Siemens data sheet the coil picks up within 13 … 50 ms and drops out within 10 … 21 ms.
Contactors in pump, fan, conveyor and compressor panels may switch thousands of times a day, and contact wear is the usual reason for replacement. Keeping a spare of the same order number avoids long stoppages.
See our Siemens industrial controls range, including SIRIUS 3RU2 overload relays and 3RV2 motor starter protectors for the same size.
Technical data
| Siemens order number | 3RT2045-1AF00 |
|---|---|
| Product | SIRIUS 3RT2 power contactor, 3-pole |
| Size | S3 |
| Utilisation category | AC-3 / AC-3e |
| Rated operational current AC-3 at 400 V | 80 A |
| Motor power AC-3 at 400 V | 37 kW |
| Motor power AC-3 at 230 V | 22 kW |
| Operational current AC-1 (40 °C, up to 690 V) | 125 A |
| Rated operating voltage, max. | 1,000 V |
| Coil voltage | 110 V AC, 50 Hz |
| Coil operating range | 0.8 … 1.1 x Us (50 Hz) |
| Coil pick-up power (50 Hz) | 296 V·A |
| Coil holding power (50 Hz) | 19 V·A |
| Auxiliary contacts (integrated) | 1 NO + 1 NC |
| Closing delay | 13 … 50 ms |
| Opening delay | 10 … 21 ms |
| Mechanical service life, typ. | 10,000,000 operating cycles |
| Power loss per pole (rated current) | 5.3 W |
| Short-circuit protection, main circuit (type 1) | gG: 250 A (690 V, 100 kA), aM: 160 A (690 V, 100 kA), BS88: 200 A (415 V, 80 |
| Ambient temperature (operation) | -25 … +60 °C |
| Connection type | screw-type terminals |
| Mounting | screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715 |
| Dimensions (W x H x D) | 70 x 140 x 152 mm |
| Net weight | 1.653 kg |
| Condition | New, original Siemens |
Typical applications
- Replacement of a worn 3RT2 contactor with the same rating
- Switching heaters and resistive loads (AC-1)
- Conveyor, mixer and packaging machine drives
- Star-delta starter assemblies
Compatibility and replacement
For overload protection mount a SIRIUS 3RU2 thermal overload relay of size S3 directly under the contactor, or combine it with a 3RV2 motor starter protector of the same size using the Siemens link module. The coil voltage is coded in the order number (here 110 V AC, 50 Hz), so check it against your control circuit before ordering.
Frequently asked questions
What coil voltage does it need?
Per Siemens: 110 V AC, 50 Hz, operating range 0.8 … 1.1 x Us (50 Hz).
How many auxiliary contacts does it have?
It has 1 NO + 1 NC integrated; more can be added with 3RH2911 auxiliary switch blocks.
Do you ship to my country, and what is the warranty?
Yes. RendatSP ships worldwide from Yiwu, China, by air in 5 to 7 days once the part is ready, and every part carries a 1-year warranty. Send the order number and quantity on WhatsApp and we will reply with a quotation.
Ordering tips
Send us the full order number from the label of the old part, or a clear photo of the label, together with the quantity you need. We check the number against the current manufacturer data before we quote and tell you if there is a newer replacement.
Need it fast? Send the order number, quantity and delivery country on WhatsApp or through the inquiry form and we reply with a quotation the same working day. All parts are new and original, covered by a 1-year warranty, and ship worldwide by air in 5 to 7 days once ready (shipping, payment and warranty). Local agents: Saudi Arabia, Iraq, the UAE, Egypt, Oman, Libya, Morocco, Mauritania, Yemen, Algeria and Jordan.
