Siemens, SIRIUS 3RU2 Thermal Overload Relay 1 NO/1 NC, 1.8A, 2.5 A F.L.C, 2.5A Contact Rating, 1.5 kW 3P
- RS stock no.:
- 706-1601
- Mfr. Part No.:
- 3RU2126-1CB0
- Manufacturer:
- Siemens
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R 1 163,95
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R 1 338,54
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Units | Per unit |
|---|---|
| 1 - 9 | R 1,163.95 |
| 10 - 14 | R 1,134.85 |
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*price indicative
- RS stock no.:
- 706-1601
- Mfr. Part No.:
- 3RU2126-1CB0
- Manufacturer:
- Siemens
Specification
Technical data sheets
Legislation and Compliance
Product Details
Find similar products by selecting one or more attributes.
Select all | Attribute | Value |
|---|---|---|
| Brand | Siemens | |
| Product Type | Thermal Overload Relay | |
| FLC Motor Rating | 1.8A, 2.5A | |
| Relay Contact Current | 2.5A | |
| Mount Type | Direct | |
| Series | SIRIUS 3RU2 | |
| Power Rating | 1.5kW | |
| Pole and Throw Configuration | 3P | |
| Terminal Type | Screw | |
| Normal State Configuration | 1 NO/1 NC | |
| Reset Method | Automatic & Manual | |
| IP Rating | IP20 | |
| Adjustable Current Range | 1.8 → 2.5 A | |
| Minimum Operating Temperature | -40°C | |
| Number of Auxiliary Contacts | 2 | |
| Width | 45mm | |
| Length | 87mm | |
| Maximum Operating Temperature | 70°C | |
| Contact Voltage | 690V ac | |
| Depth | 73mm | |
| Standards/Approvals | IEC, EAC, WEEE (2012/19/EU), REACH, CE, UKCA, RoHS, UL, CCC | |
| Select all | ||
|---|---|---|
Brand Siemens | ||
Product Type Thermal Overload Relay | ||
FLC Motor Rating 1.8A, 2.5A | ||
Relay Contact Current 2.5A | ||
Mount Type Direct | ||
Series SIRIUS 3RU2 | ||
Power Rating 1.5kW | ||
Pole and Throw Configuration 3P | ||
Terminal Type Screw | ||
Normal State Configuration 1 NO/1 NC | ||
Reset Method Automatic & Manual | ||
IP Rating IP20 | ||
Adjustable Current Range 1.8 → 2.5 A | ||
Minimum Operating Temperature -40°C | ||
Number of Auxiliary Contacts 2 | ||
Width 45mm | ||
Length 87mm | ||
Maximum Operating Temperature 70°C | ||
Contact Voltage 690V ac | ||
Depth 73mm | ||
Standards/Approvals IEC, EAC, WEEE (2012/19/EU), REACH, CE, UKCA, RoHS, UL, CCC | ||
- COO (Country of Origin):
- DE
Siemens 3RU2 Series Thermal Overload Relay, 1.8 to 2.5A Adjustable Current Range, 1.5kW Power Rating - 3RU2126-1CB0
This thermal overload relay provides adjustable motor protection for three-phase circuits, detecting overloads and signalling trips for control systems. It is designed for direct mounting with screw connections and supports both manual and automatic reset modes, making it suitable for industrial control panels operating in a wide ambient temperature range.
Features & Benefits
• Adjustable current range 1.8 to 2.5A for precise motor protection
• Trip class 10 minimises nuisance trips for intermittent loads
• Rated operational voltage up to 690V for high-voltage systems
• Integrated auxiliary switch with 1 NO and 1 NC for status signalling
• Auxiliary contact currents rated to 3A at low voltages for control reliability
• IP20 front protection for safe finger-safe operation
• Trip class 10 minimises nuisance trips for intermittent loads
• Rated operational voltage up to 690V for high-voltage systems
• Integrated auxiliary switch with 1 NO and 1 NC for status signalling
• Auxiliary contact currents rated to 3A at low voltages for control reliability
• IP20 front protection for safe finger-safe operation
Applications
• Suitable for protecting small three-phase motors up to 1.5 kW
• Ideal for use with contactors in industrial control panels
• Used with automation systems requiring overload feedback
• Can be used for motor starter assemblies in HVAC equipment
• Suitable for installations exposed to -40 to 70 °C ambient temperatures
• Ideal for use with contactors in industrial control panels
• Used with automation systems requiring overload feedback
• Can be used for motor starter assemblies in HVAC equipment
• Suitable for installations exposed to -40 to 70 °C ambient temperatures
How is the device connected to the main and auxiliary circuits?
Main and auxiliary circuits use screw-type terminals with top-and-bottom wiring for the main conductors and separate screws for auxiliaries.
What conductor sizes can be terminated on the main contacts?
Main contacts accept solid or stranded conductors from 1mm² up to 10 mm², including provisions for two conductors per Terminal where specified.
What electrical endurance can be expected for the auxiliary contacts?
Auxiliary contacts are rated for AC-15 switching with currents up to 3A at 24 to 125V and lower permissible currents at higher voltages, with contact rating B600/R300.
How is short-circuit protection for the auxiliary switch achieved?
Recommended protection for the auxiliary circuit uses gG fuses at 6A or fast fuses at 10A as specified for short-circuit protection.
Note
Screw Terminals can only be used with screw Terminal overloads and spring Terminals can only be used with spring Terminal overloads.
Approvals
CE, UL, CSA
Related links
- Siemens 1.8A 2.5A Contact Rating, 0.75 kW 3P
- Siemens 3.5A 5A Contact Rating, 1.5 kW 3P
- Siemens 2.5A F.L.C 1.5 kW, 690V ac 3P
- Siemens 3.5A 5A Contact Rating, 4 kW 3P
- Siemens 2.5A F.L.C 1.5 kW, 690V
- Siemens 2.8A 4A Contact Rating, 3 kW 3P
- Siemens 3A Contact Rating, 15 kW 3P
- Siemens 2.2A 3.2A Contact Rating, 2.2 kW 3P