What is Restrike Time

Horace He

Last Updated: August 14, 2023

What is Restrike Time

Restrike time is the duration it takes for a lamp, particularly high-intensity discharge (HID) lamps, to reignite or restrike after being turned off. When a lamp is shut off, it needs a certain amount of time to cool down before it can be re-lit. During operation, HID lamps reach high temperatures and pressures, and the ballast of the fixture requires time to strike a new arc in the lamp.

The restrike time can vary depending on the specific lamp and ballast used. Metal halide lamps, which is a type of HID lamp, have a restrike time of 15 to 20 minutes. This means that after these lamps are turned off, it will take approximately 15 to 20 minutes for them to cool down and be ready to reignite.

Restrike time is an important consideration in lighting systems, especially in applications where immediate or quick re-illumination is required. In situations like sports stadiums, where the lights may need to be turned off and on again, a long restrike time can cause delays and inconvenience for patrons. To address this issue, there are technologies available, such as instant restrike systems, that allow lamps to reignite almost immediately after being turned back on.