MN 12 Thermal Overload Relay 270-450A 415V AC Class 10A | L&T – SS94139OORO

Name: L&T MN12 Thermal Overload Relay 270-450A | SS94139OORO
Brand: Lauritz Knudsen (L&T)
SKU: SS94139OORO
Price: 13266.00 INR
Availability: InStock

SKU: SS94139OORO

Original price was: ₹22,110.00.Current price is: ₹13,266.00. Excl. GST

11 People watching this product now!

Order protection

Buy with complete confidence.

We back each order with genuine supply, on-time dispatch and GST or commercial invoicing as required.

Buyer protection on every order

Global DeliveryShipped pan-India and to export markets.

On-Time DeliveryPacked and dispatched on schedule.

100% OriginalFrom brand-authorised channels only.

GST InvoiceCompliant, ITC-ready tax invoice.

Secure PaymentEncrypted, trusted payment gateways.

Also included Dedicated account manager Technical support Bulk & business pricing 3-day replacement

Looking for the MN 12 Thermal Overload Relay 270-450A 415V AC Class 10A | L&T? This genuine SS94139OORO overload relay is built for motor control and switching, combining proven reliability with full compliance to applicable IEC/IS standards. Key ratings include 270–450 A, 415V AC. Order part number SS94139OORO from myelectric.in — a trusted SS94139OORO supplier offering competitive pricing, GST billing, and shipping across India and overseas.

📋 Technical Specifications

Parameter	Value
Brand	SS94139OORO
Part Number / SKU	SS94139OORO
Category	Overload Relay
Current Rating	270–450 A
Voltage Rating	415V AC
Trip Class	Class 10A (≤10 s at 7.2 × FLC, per IEC 60947-4-1)
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 where applicable

⚡ Key Features

Adjustable current range 270–450 A — set to the motor nameplate FLC for accurate overload detection; range covers multiple motor sizes from a single relay model.
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.
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 where applicable — meets Indian regulatory requirements for use in government, commercial, and industrial electrical installations.
Genuine authorised SS94139OORO 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 270–450 A adjustable range on the SS94139OORO for my motor?

A: Turn the setting dial to the motor’s nameplate full-load current (FLC) — the FLC must fall within the 270–450 A range of this device. Setting it at the motor FLC (not the maximum of the range) gives correct overload trip timing while still riding through normal starting inrush. If the motor FLC is outside this range, select the adjacent rating in the same series.

Q: How do I set the SS94139OORO 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) — ensure the FLC is within the 270–450 A range of this relay. 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 SS94139OORO provide single-phase (phase loss) protection?

A: SS94139OORO 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 SS94139OORO?

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 SS94139OORO when the application specifically requires overload relay characteristics.