Omron H3CR-A8E 100/240VC H3CR Series Solid-State Timer

Description

Providing reliable timing control within industrial control panels, the Omron H3CR-A8E 100/240VC solid-state timer is engineered for precision sequencing and delay operations. This 8-pin model features a unique output configuration combining a time-limit SPDT contact with an instantaneous SPDT contact, allowing for immediate secondary circuit activation upon power-up alongside delayed system execution. With its broad operating range and robust electrical design, it serves as a core coordination component in motor starters, conveyor systems, and sequential machine logic.

Key Features

• Dual Contact Output: Integrates 1 SPDT time-limit output and 1 SPDT instantaneous output for advanced sequence initiation.
• Wide Operating Range: Wide timing selection from 0.05 seconds to 300 hours across multiple field-selectable ranges.
• Universal Supply Voltage: Operates reliably on fluctuating AC grids from 100 to 240 VAC (50/60 Hz).
• Standard Plug-In Base: Uses an 8-pin circular octal base compatible with standard industrial sockets.
• Clear Diagnostic Indicators: Front-panel LEDs provide instant visual verification of power input and contact state.

Applications

• Motor Starter Star-Delta Transitions: Manages transient transition delays to prevent mechanical damage.
• Conveyor System Sequencing: Schedules sequential belt initialization to avoid electrical surge stacking.
• Machine Tool Automation: Interlocks auxiliary lubrication or cooling pumps with spindle delays.
• HVAC Damper Interlocks: Synchronizes fan activation with automated damper opening cycles.

Technical Specifications

Connections and Interfaces

Empirical Engineering Insights

Alternative Models & Compatibility

The H3CR-A8E model is specifically chosen when a fast bypass or control path initialization is required alongside a delayed circuit. If replacing this unit with a standard H3CR-A8, note that the standard A8 model utilizes both SPDT contacts as time-limit delayed outputs. Substituting an A8E with an A8 without modifying the terminal base wiring will disable instantaneous functionality, causing interlocking or immediate auxiliary component startup to fail.

Application Pitfalls & Engineering Notes

When switching inductive loads such as solenoid valves or heavy contactor coils, ensure that external surge suppressors (RC networks for AC, snubbing diodes for DC) are placed across the load. Switching unsuppressed inductive loads leads to high contact arcing, drastically reducing the H3CR-A8E’s internal relays' life expectancy and inducing EMI into neighboring PLC input modules.

Commissioning & Wiring Tips

Always utilize Omron-approved sockets (such as P2CF-08 for surface/DIN rail mounting, or P3G-08 for back-connecting panel mounts). Maintain terminal screw torques between 0.78 and 1.18 N-m to prevent thread stripping while ensuring vibration-proof mechanical connection of field conductors.

Installation Guidelines