Omron H3CR-G8L AC200-240 Star-Delta Timer

Technical Overview

The Omron H3CR-G8L AC200-240 is a high-performance, compact solid-state star-delta timer designed to facilitate smooth, sequential starting of three-phase AC motors. Operating on a dedicated 200 to 240 VAC supply, this 1/16 DIN (48 x 48 mm) analog timer prevents high inrush currents and severe mechanical shocks on initial power-up. It incorporates an 8-pin plug-in terminal layout and provides individual time-limit SPST-NO outputs for both star and delta circuits. Designed with a wide star-time operation range of up to 120 seconds and adjustable star-delta transfer times up to 1.0 second, this timer is ideal for critical motor transition control panel assemblies.

Key Features

Compact 1/16 DIN standard body (48 x 48 mm) ideal for space-constrained control panels.
Dual SPST-NO relay outputs specifically configured for star-to-delta transition sequences.
Four adjustable star-operation time scales from 0.5 seconds up to 120 seconds.
Six selectable star-delta transfer times (0.05s, 0.1s, 0.25s, 0.5s, 0.75s, 1.0s) to prevent phase short circuits.
Easy installation and servicing using an 8-pin plug-in octal socket interface.
Meets strict international certifications including UL508, CSA, NK, Lloyds, and CCC.

Technical Specification Matrix

Parameter	Value
Supply Voltage	200 to 240 VAC
Supply Frequency	50/60 Hz
Operating Voltage Range	85% to 110% of rated supply voltage
Power Consumption	Approx. 12 VA (3.0 W) at 240 VAC
Pin Configuration	8-pin
Timing Function	Star-delta timer
Star-Time Ranges	0.5 to 6 s, 1 to 12 s, 5 to 60 s, 10 to 120 s
Star-Delta Transfer Time	Selectable: 0.05 s, 0.1 s, 0.25 s, 0.5 s, 0.75 s, or 1.0 s
Output Type	Time-limit: SPST-NO (star), SPST-NO (delta)
Contact Rating	5 A at 250 VAC / 30 VDC (resistive load)
Reset Method	Self-reset / Power-opening
Minimum Power-Opening Time	0.5 s
Operating Ambient Temperature	-10°C to 55°C (with no icing)
Operating Ambient Humidity	35% to 85%
Degree of Protection	IP40 (panel surface)

Industrial Applications

1. Industrial Air Compressor Starter Control Panels

Used in heavy-duty air compressor panels to control the star-to-delta start cycle of 3-phase induction motors. The timer runs the motor in star configuration to overcome compressor inertia before switching to delta mode.

Problem Solved

Eliminates high starting inrush currents that trigger upstream circuit breakers, overheat motor windings, and cause line-voltage sags on the 200-240V supply grid.

Inrush Current MitigationCompressor Control PanelsMotor Windings ProtectionSequential Starter

2. Wastewater Centrifugal Pump Slow-Start Panels

Coordinates the transition from star to delta connections on high-volume municipal or agricultural wastewater centrifugal pumps operating within -10°C to 55°C environments.

Problem Solved

Avoids severe water hammer effects and extreme mechanical torque spikes on pump bearings and pipe fittings, prolonging system lifespan and reducing leak potential.

Centrifugal PumpsWater Hammer PreventionTorque Spike SuppressionWastewater Management

3. HVAC Fan Soft-Starting on Industrial Ventilation Systems

Controls the soft-starting cycle of large high-inertia ventilation blowers and extraction fans utilized in industrial manufacturing plants and agricultural warehouses.

Problem Solved

Prevents immediate mechanical stress and wear on motor belts, pulleys, and fan blades from abrupt sudden torque, ensuring high system uptime.

HVAC StarterBelt Drive ProtectionHigh-Inertia VentilationBelt Slippage Prevention