Schneider Electric LR97D38B TeSys D Electronic Overload Relay 20-38 A 24 V AC/DC LC1D Relay

The Schneider Electric LR97D38B is a TeSys LR97D electronic overcurrent relay for direct mounting under a LC1D25...D38 contactor, adjustable over 20-38 A on its LOAD dial with a 20-34 A tripping threshold. It is supplied from 24 V AC/DC and adds adjustable O-TIME and D-TIME dials plus phase-failure detection that a plain bimetallic relay cannot match.

Technical Specifications

Certifications & Standards

• GOST
• CSA
• UL
• IEC 60947
• IEC 60255-6

Selection Notes

The 20-38 A LOAD dial covers LC1D25...D38 contactors; set it to the motor's actual full-load current rather than the top of the range so the 20-34 A tripping threshold protects the winding instead of the contactor's maximum rating. The D-TIME dial (0.5-30 s) should match the motor's real starting time so the relay rides through inrush without nuisance tripping, while O-TIME (0.3-10 s) sets how long a steady-state overcurrent above 3×LOAD is tolerated before the relay opens its 1 C/O contact. Pick the 24 V AC/DC variant to match the control transformer already feeding the rest of the panel; the current-setting dials are identical across every supply-voltage variant in this range.