Overview
The Thomas Research ESP-125 is a traditional 120V control system that incorporates current-sensing circuitry to automatically activate an auxiliary quartz lamp when the main HID lamp is extinguished. Designed for rapid restrike functionality, the ESP-125 ensures uninterrupted lighting in facilities where HID lamp failures cannot be tolerated. This quartz restrike controller operates on HID circuits from 39 to 1500 watts with auxiliary lamp support up to 500W, making it suitable for a wide range of industrial, commercial, and emergency lighting applications.
Key Features
- Current-Sensing Technology: Measures the current drawn by the HID circuit rather than voltage across the circuit allowing use with virtually any type of lamp or ballast circuit
- Wide Operating Range: Operates on HID circuits from 39-1500 watts and operates auxiliary lamps up to 500W
- Automatic Restrike: Built-in timer to keep the quartz lamp on for 2-3 minutes during the HID lamp warm-up period
- Ballast Compatibility: For use with HPS or Metal Halide (probe-start or pulse start) magnetic ballasts with a 120V tap or input
- Non-Arcing Switches: Non-arcing switches allow the ESP-125 to be used in Class 1, Division II vapor tight fixtures
- Simple Installation: Compact and simple to wire
Technical Specifications
- Input Voltage: 120V AC
- Frequency: 50/60 Hz
- HID Circuit Range: 39–1500 watts
- Auxiliary (Quartz) Lamp Load: Up to 500W maximum
- Control Type: Current-sensing automatic restrike
- Timer Duration: 2–3 minutes (timed version)
- Enclosure: High temperature, flameproof plastic
- Surface Temperature Rating: 105°C maximum
- Suitable for Class 1, Division II vapor tight fixtures
- Compatible with emergency generator power
Typical Applications
- Emergency Lighting Systems: Ensures continued illumination in safety-critical facilities when primary HID lamps fail.
- Industrial Manufacturing: Maintains continuous lighting in production areas where downtime is costly.
- Warehouse and Storage: Provides rapid restrike capability for large HID lighting systems in high-bay facilities.
- Outdoor Security Lighting: Automatic auxiliary lamp activation for perimeter and parking lot illumination.
- Hazardous Locations: Non-arcing design permits use in Class 1, Division II environments (vapor tight fixtures).
- Facility Maintenance: Drop-in retrofit for existing HID magnetic ballast circuits requiring failsafe auxiliary lighting.
Compatibility & Replacements
Compatible With
- HPS (High Pressure Sodium) lamps with magnetic ballasts
- Metal Halide lamps (probe-start and pulse-start types)
- Magnetic ballasts with 120V tap or input
- Standard quartz auxiliary lamps (up to 500W)
- Emergency generator power systems
- Class 1, Division II vapor tight lighting fixtures
Replaces / Drop-In Replacement For
- Older or failed quartz restrike controllers in HID lighting systems
- Manual restrike systems requiring auxiliary lamp activation
Works With
- Standard 120V facility electrical systems
- Magnetic ballast circuits (probe-start and pulse-start configurations)
- Emergency backup power systems
- Industrial facility automation and lighting management networks
