3RN20102CA30 | thermistor motor protection relay compact evaluation unit 17.5 mm enclosure springloaded terminal 1 NO contact, 1 NC contact Us = 24 V AC/DC Auto RESET suitable for bimetallic switch 2 LEDs (ready/tripped) electrical isolation Siemens
€335.99 Original price was: €335.99.€154.55Current price is: €154.55. Excl. GST
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The Siemens 3RN20102CA30 is an overload relay, engineered for motor control and switching in demanding Indian and international installations. Key ratings include 24V AC. Buy the 3RN20102CA30 | thermistor motor protection relay compact evaluation unit 17.5 mm enclosure springloaded terminal 1 NO contact, 1 NC contact Us = 24 V AC/DC Auto RESET suitable for bimetallic switch 2 LEDs (ready/tripped) electrical isolation Siemens online at myelectric.in with GST invoice, genuine-product assurance, and fast delivery across India — bulk and worldwide export enquiries welcome.
📋 Technical Specifications
| Parameter | Value |
|---|---|
| Brand | Siemens |
| Part Number / SKU | 3RN20102CA30 |
| Category | Overload Relay |
| Voltage Rating | 24V AC |
| Phase-Loss Sensitivity | Yes — differential bimetal mechanism |
| Reset Mode | Manual / Automatic (selectable) |
| Auxiliary Contacts | 1 NO + 1 NC |
| Mounting | Direct mounting on matching contactor |
| Rated Frequency | 50/60 Hz |
| Standard | IEC 60947-4-1 / IS 13947-4-1 |
| Certifications | BIS certified, CE, cULus (select models) |
⚡ Key Features
- Bimetal thermal element with phase-loss sensitivity — independently monitors each phase; trips if any phase carries more than ~115% of the set current, or on complete phase failure.
- Normally open (NO) and normally closed (NC) auxiliary contacts built in — NO contact wired to motor run indicator; NC contact wired to PLC fault input or motor starter stop circuit.
- Manual/automatic reset selectable — set to manual for attended machinery requiring operator acknowledgement; auto-reset for unattended remote installations.
- Manufactured to IEC 60947-4-1 / IS 13947-4-1 — complies with the applicable Indian BIS and IEC international standards for this product category.
- BIS certified, CE, cULus (select models) — meets Indian regulatory requirements for use in government, commercial, and industrial electrical installations.
- Genuine authorised Siemens product — sourced directly from the official distribution network with full manufacturer traceability and warranty.
- GST invoice provided for India orders — valid for corporate procurement, government project orders, and public tender supply via myelectric.in.
- Worldwide export available — UAE, Singapore, UK, USA, Sri Lanka & more. Contact +91 94814 00316 for bulk pricing and international shipping.
❓ Frequently Asked Questions
Q: How do I set the 3RN20102CA30 to protect a motor without causing nuisance trips on starting?
A: Set the thermal overload dial to the motor’s nameplate full-load current (FLC). For star-delta starters, set the overload relay to 58% of motor FLC (line current in delta = FLC × 0.58). Allow 10 trips for the relay’s thermal memory to stabilise before adjusting the setting.
Q: Does the 3RN20102CA30 provide single-phase (phase loss) protection?
A: Siemens thermal overload relays include single-phase sensitivity: if one phase is lost, the remaining phases carry higher current, causing the bimetal to heat and trip within the specified time. For critical motors, add a dedicated phase-loss relay for faster response independent of load — overload relay phase-loss protection is load-dependent and may take minutes to trip at light load.
Q: What is the difference between an Overload Relay and a standard MCB — and why use the 3RN20102CA30?
A: A standard MCB protects against overload and short-circuit only. An Overload Relay provides thermal overload protection calibrated to motor FLC, protecting the motor from sustained overloads that would destroy windings before a standard MCB trips. Choose the 3RN20102CA30 when the application specifically requires overload relay characteristics.













