Delixi JR28-25 Thermal Overload Relay 12-18A

The Delixi JR28-25/12-18 is a bimetallic thermal overload relay with an adjustable current setting range of 12 to 18A, designed for din-rail mounting and direct combination with Delixi CD10 contactors (9A to 32A frame) to form complete IEC 60947-4-1 compliant motor starters. The JR28 series is Delixi's equivalent to the Schneider Electric LRD thermal overload relay family — the most widely used overload relay in the TeSys D ecosystem — and shares identical mounting dimensions and connection interface with LRD relays in the corresponding current range. This means a JR28-25/12-18 can be clipped directly onto the front of a CD10-25/220V or CD10-32 contactor, or onto a Schneider Electric TeSys D LC1D25 or LC1D32 contactor, using the standard snap-fit mounting without tools. This cross-compatibility is a significant operational advantage in Saudi Arabia's MCC maintenance environment, where a single site may contain both TeSys D and CD10 based starters in parallel across different installation vintages.

The 12-18A current setting range of the JR28-25/12-18 covers three-phase induction motors in the 5.5 kW to 7.5 kW range at 400 V (assuming rated full-load currents of approximately 12A at 5.5 kW and 16A at 7.5 kW), making this the standard overload relay for AHU supply fan motors, chiller circulating pump motors, cooling tower fan drives, and similar HVAC equipment in Saudi commercial buildings. At the upper end of the 12-18A range, the relay also covers 9 kW motors operating at partial load, providing a single relay that spans a useful band of common building services motor sizes. The adjustable bi-metal element with tamper-resistant graduated scale allows site commissioning engineers to set the relay precisely to the motor's nameplate full-load current during installation, rather than accepting a fixed current rating.

In Saudi Arabia's climatic context, the temperature compensation of the JR28-25/12-18 is a technically important characteristic. Standard bimetallic overload relays are calibrated to trip at 20°C ambient; in Saudi Arabia's unconditioned electrical rooms, switchrooms, and external distribution kiosks, ambient temperatures of 40–50°C are common in summer months. The JR28-25/12-18 incorporates a temperature compensation mechanism that adjusts the bimetal trip threshold across the ambient temperature range, preventing both nuisance tripping in hot electrical rooms and failure to trip at elevated motor temperatures in cool rooms. This compensation characteristic is essential for reliable motor protection in the Saudi climate and is a key selection criterion for MEP engineers specifying overload relays for commercial building projects in Riyadh, Jeddah, Dammam, and coastal locations.

Razz Middle East supplies the JR28 range in all current settings from 0.1A to 40A, covering the full range of motor sizes encountered in commercial building services, light industrial, and process plant applications. We stock JR28-25/12-18 in volume for AHU and pump starter kits, and can supply matched CD10-25/220V contactors and CDM1-100M/3300 MCCBs as a complete, type-coordinated motor starter package for panel builders constructing MCCs and distribution boards across the Kingdom. Technical documentation including IEC 60947-4-1 coordination tables confirming the type-2 coordination class between CD10 contactors and JR28 overload relays is available from our technical team.