SQUARE D
SQUARE D LRD21L Overload Relay 12-18 A Trip Class 20 690 V AC
Thermal overload relay protects three-phase motors from 12 to 18 amps with Trip Class 20 at 690 V AC
- Adjustable 12-18 A range protects varied motor loads
- Trip Class 20 suits standard motor starting profiles
- 690 V AC rating fits industrial control circuits
- Direct contactor mounting simplifies panel assembly
- Auto and manual reset options speed recovery
Application Scope
The Schneider Electric LRD21L is a thermal overload relay designed for three-phase motor circuits up to 690 V AC. It suits maintenance engineers and panel builders who need reliable overload protection for contactors in industrial machinery. Buyers who require electronic trip units or communication-enabled monitoring will not find those functions in this device.
Current Setting Range
The adjustable trip range spans 12 A minimum to 18 A maximum, making this the decisive specification for matching the relay to the motor full-load current. Selecting a relay outside this window leaves the motor unprotected or causes nuisance tripping, so verify the nameplate current before ordering.
Sustained Load Behaviour
Trip Class 20 allows the relay to withstand starting inrush for up to 20 seconds before tripping on a sustained overload, reducing false shutdowns during heavy starts. The thermal element reacts to prolonged overcurrent rather than momentary peaks, and the auto-manual reset lets operators choose automatic restart or deliberate intervention after a trip event.
Highlights
- Adjustable 12-18 A range protects varied motor loads
- Trip Class 20 suits standard motor starting profiles
- 690 V AC rating fits industrial control circuits
- Direct contactor mounting simplifies panel assembly
- Auto and manual reset options speed recovery
Specifications
| Brand | SCHNEIDER ELECTRIC |
|---|
Questions about this item
What does the 12-18 A range mean when the relay is installed on a motor starter?
The relay protects motors drawing between 12 A and 18 A full-load current; set the dial to the exact motor nameplate value within that window.
How does the 690 V AC rating and screw-clamp terminals limit the circuits I can use it on?
It is rated for three-phase supplies up to 690 V AC; the screw-clamp terminals accept solid or stranded conductors sized for the 12-18 A range.
What contactor does the LRD21L mount onto and how is it fixed?
It mounts directly onto TeSys Deca contactors using the built-in direct-mount style; no separate bracket or DIN rail adapter is required.
Also in this aisle
People compared these
Same shelf, same checkout — eight coins and a 30-minute rate lock.
