Schneider Electric LRE322 EasyPact TVS 17-25 A Overload Relay

LRE322: 17 to 25 A thermal overload relay for LC1E starters

The LRE322 is a Schneider Electric product listed in its datasheet as: EasyPact TVS differential thermal overload relay 17…25 A – class 10A. It is the thermal overload part of a motor starter: it follows the current drawn by the motor and opens a signalling contact when an overload or a lost phase would otherwise overheat the windings. Seven Star LLC supplies the LRE322 in Oman and the GCC as an independent supplier based in Muscat.

The reference tells you the family and the band. LRE is the device short name given in the datasheet, the range is Easy TeSys Protect, and the title states the adjustable window, 17 to 25 A, together with trip class 10A. The two or three digits after LRE are the range code of that band. The LRE322 is built on the larger body (70 mm wide) for the LC1E40 to LC1E95 contactors. The 17 to 25 A window on the larger body is the relay for LC1E40 to LC1E95 contactors, so it is the choice when the starter is built on a bigger contactor frame but the motor current is still modest.

Technical specifications of the LRE322

Where the LRE322 sits in an LC1E starter

The datasheet lists the compatible contactors for the LRE322 as LC1E40 to LC1E95. Mounting options are listed as under contactor; plate, with specific accessories; rail, with specific accessories. In a normal starter the relay plugs directly under the contactor, which keeps the power wiring short and gives a compact direct-on-line starter without extra links.

The body measures 70 mm wide, 54 mm high and 113 mm deep with a net weight of 0.47 kg; the packed unit weighs 482 g. Because the contactor list starts at LC1E40, this relay is not an alternative to the LRE22 on a small starter; match the frame to the contactor before you match the current.

Typical uses in Oman and the GCC

Starters of this type are found in water and desalination auxiliaries, oil and gas utility skids, power station balance-of-plant and building services across Oman and the GCC. The 17 to 25 A window on the larger body is the relay for LC1E40 to LC1E95 contactors, so it is the choice when the starter is built on a bigger contactor frame but the motor current is still modest..

Heat and dust are the practical enemies. The datasheet allows -20 to 60 °C without derating conforming to IEC 60947-4-1 without derating and IP20 protection, so the LRE322 belongs inside a closed, ventilated panel; in summer the inside of a sunlit enclosure can be far above the outdoor mean, so compare your measured panel temperature with that limit.

Trip behaviour of the LRE322

The dial of the LRE322 spans 17 to 25 A. The datasheet states a tripping threshold of 1.14 +/- 0.06 Ir conforming to IEC 60947-4-1, so the relay is designed to act when the motor current reaches about 1.14 times the dialled value, with a tolerance of 0.06 times. At the top of the scale that is roughly 28.5 A and at the bottom roughly 19.4 A.

It is a differential relay, which matters on a three-phase motor. The datasheet gives a tripping current of 130 % of Ir on two phases while the third phase is at zero, conforming to IEC 60947-4-1; at the top of the dial 25 A that corresponds to about 32.5 A in each of the two live phases. A broken fuse or loose terminal therefore does not leave the motor running single-phased unnoticed.

Class 10A is the fast characteristic for motors that start quickly; the class number is the longest tripping time in seconds at 7.2 times the setting current under IEC 60947-4-1. Temperature compensation is listed over -20 to 60 °C, so the setting does not wander with panel temperature inside that band.

Selection checklist for the LRE322

• Motor nameplate current inside 17 to 25 A, ideally near the middle of the dial.
• Contactor in the starter must be one of LC1E40 to LC1E95.
• Class 10A: confirm that the load starts quickly enough for this characteristic.
• Upstream short-circuit device: 50 A gG or 25 A aM, per the datasheet.
• Space: allow 70 mm x 54 mm x 113 mm and 0.47 kg.
• Say whether the relay is for a new starter or replaces one that has tripped out of service.

The LRE322 among its nearest ranges

The table places the LRE322 between its nearest neighbours in this group, using the datasheet values of each. It helps when the nameplate current sits near a boundary or when the contactor decides the frame.

Commissioning, reset and spares

Set the dial of the LRE322 to the nameplate current of the motor, not to the contactor rating. Use the red stop push-button to confirm the contactor drops and the green reset push-button to restore the relay afterwards. After any short-circuit event inspect the relay and starter, because the overload relay does not replace the upstream fuse or breaker.

For spares keep the same reference instead of choosing by range alone, since the compatible contactor list differs from band to band (LC1E40 to LC1E95 for the LRE322). If you are unsure, send the contactor reference and the motor nameplate current and we will confirm the matching member of the family.

Information to send with an RFQ for the LRE322

• Full reference LRE322 and the quantity required
• Motor nameplate current, voltage and power
• Contactor reference the relay will be fitted to
• Delivery location and timing
• New starter, replacement or spare

Documents and quotation

A datasheet for this product is attached on this page. It lists the electrical, mechanical and environmental data summarised above, and it is the document to check against your own drawings.

Send us the part number, quantity and application and we will confirm availability and a quotation. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.