What is the expected bulb life of infra red illuminators?

The 500-Watt version of the Dennard IR Lamp has a rating of 4000 hours. It is a bulb that has been especially designed for the Dennard lamp. The 300-Watt version has a rating of 2000 hours.

Bulb life can be affected significantly by supply voltage. In areas where the voltage present is higher than normal (greater than 230V) a voltage reducer is available and may be required to incease the bulbs life.

In general lamps have an expected bulb life of 2000 to 3000 hours @ 230V, however some 12V units can have a longer life.