The K4021C Series Fixed Position Mounting Photo Control is a thermal-type photo control that fits into a standard outlet box, post lamp, or wall pack. The photo control provides dusk-to-dawn lighting control, along with a delay action, which eliminates loads switching OFF due to car headlights and lightning. The thermal-type control features a cadmium sulfide photocell and a sonic-welded polycarbonate case and lens to seal out moisture. The design utilizes a dual temperature compensating bimetal and composite resistor for reliable long life operation over ambient temperature extremes.

  • Model Overview
  • Specifications
  • Resources
  • Cadmium sulfide photocell
  • Sonic-welded polycarbonate housing and lens to seal out moisture
  • Delay action eliminates load switching OFF due to car headlights and lightning
  • 9" leads
  • K4321 includes a weatherproof wall plate with neoprene gasket
  • Most models equipped with 5/8" - 18" threaded side mounting, locking nut and washer gasket
Product Ratings
CA Title 20 Listed
Watts Tungsten: 1800
VA Ballast: 1000
Amps Tungsten: 15
Amps Ballast: 8.3
Volts: 120
Replaced By: -
California Title 24 Compliant: Yes

The need to get the installation industry comfortable with the [LED] technology motivated Intermatic Inc., Spring Grove, IL, to develop a comprehensive new testing approach to help inform electrical contractors of the performance of its lighting control portfolio when LED lighting is used.

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