The Schneider Electric LR3D1522 is a TeSys LRD non-differential thermal overload relay for motor protection, with a thermal protection adjustment range of 17...25 A and a Class 20 tripping curve per IEC 60947-4-1. It provides phase-failure sensitivity — tripping at 130% of set current Ir on two phases with the third at zero — and includes a 1 NO + 1 NC auxiliary contact set for signaling the overload condition back to the control system.
The 17...25 A adjustment range sets the motor full-load current window this relay protects. Class 20 means it allows up to 20 seconds of locked-rotor current before tripping — standard for general-purpose induction motors driving pumps, fans, and conveyors. Rated insulation voltage (Ui) is 600 V for CSA/UL applications and 690 V per IEC 60947-4-1, with an impulse withstand of 6 kV. The relay mounts directly under a TeSys D contactor or on a DIN rail with specific accessories. The signalling circuit is rated 1.5 A at 240 V AC-15 and 0.1 A at 250 V DC-13 — enough to drive a PLC input or a pilot light, but not a contactor coil directly. Fuse the signalling circuit at 4 A gG or BS maximum.
Certified to EN/IEC 60947-4-1, EN/IEC 60947-5-1, UL 60947-4-1, UL 60947-5-1, CSA C22.2 No 60947-4-1, CSA C22.2 No 60947-5-1, and GB/T 14048.4/14048.5. Flame retardance is V1 per UL 94.