Sequence and Phase Fail Relay Manufacturer,Supplier and Exporter in India
Product Code : EL-BE-12862
Jlab Export is a leading Sequence and Phase Fail Relay Manufacturer,and suppliers in India
Sequence and Phase Fail Relay (code EL-BE-12862), model LH221/4-9, is a voltage protection relay for three-phase supply lines. It watches the incoming supply and cuts off the circuit quickly when it finds a fault, so that abnormal voltage is not sent on to the connected appliance. Jain Laboratory Instruments Pvt Ltd builds it at Ambala in India under the JLab name.
Specifications
| Parameter | Detail |
|---|---|
| Model | LH221/4-9 |
| Supply system | Three-phase (3 phase) |
| Faults detected | Over-voltage, under-voltage, phase failure, phase reversal |
| Action on fault | Cuts off the circuit quickly |
| Electronics | High-speed, low-power processor at its core |
| Indicator | Indicator light |
| Quality check | Each relay is visually inspected before dispatch |
| Pack quantity | Each (sold individually) |
| Minimum order quantity | 10 units |
| Dispatch time | Usually 7–10 working days |
| Product code | EL-BE-12862 |
| Manufacturer | Jain Laboratory Instruments Pvt Ltd (JLab) — OEM |
| Country of origin | India (made in Ambala, Haryana) |
What Is a Sequence and Phase Fail Relay Used For?
A three-phase load expects three balanced phases arriving in the right order. If the sequence is reversed, a three-phase induction motor turns the wrong way; if one phase is lost, the load is left on an unbalanced supply. A phase monitoring relay checks the incoming line for both conditions, and for voltage that has drifted too high or too low, so that the equipment it feeds is disconnected instead of running on a faulty supply.
Frequently Asked Questions
Is this an electronic relay?
Yes. Its core is a high-speed, low-power processor.
What causes phase reversal?
Swapping any two of the three supply conductors reverses the phase sequence, so the phases reach the load in the wrong order.
How does this relay differ from the JLab contactor?
The contactor (model LH 202/4-1) switches electrical loads on and off from a control circuit. This relay is a protection device: it monitors the three-phase supply and disconnects the circuit when a voltage or phase fault appears.
What should an export enquiry include?
The number of relays, the destination country and port or city, and the delivery terms you prefer, such as FOB or CIF.
Who makes the relay?
JLab (Jain Laboratory Instruments Pvt Ltd) makes it in Ambala, Haryana, India.
OEM Manufacturer
JLab is the trading name of Jain Laboratory Instruments Pvt Ltd, an Indian maker of laboratory and electrical equipment, incorporated in 2017 and based on Hargolal Road, Ambala, Haryana. This relay comes out of JLab’s own works rather than from a trader’s stock, so institutions, dealers and importers deal with the manufacturer directly, and repeat orders are handled by the same team. JLab exports worldwide and ships to buyers in every region — for example Gabon in Central Africa, Tonga in Oceania, Sudan in North Africa, Belgium in Western Europe and Tanzania in East Africa.
Related Switchgear and Control Items
- Contactors (model LH 202/4-1) — four NO and one NC contact, with overload protection, rated at 10 kW.
- Circuit Breakers (model LH229/4-13) — a single-pole, DIN-rail mounted breaker with thermal-magnetic overcurrent protection.
- Relays — a contactor relay with three NO and three NC contacts for switching auxiliary and control circuits.
- Indicator Lights — LED panel indicators in red, blue, yellow and green.
Browse the Basic Electronics range or the wider Electronics Lab Equipments section.
Request a Quote
To ask for a quotation, press Add To Cart on this page or write through the contact page, stating the model, how many relays you need and where they should be delivered.
Last updated: 22 October 2026
