NEC VT58 User Manual page 61

6. Maintenance
6. Connect the supplied power cable, turn on the Main Power switch and turn on the projector.
7. Finally, select the menu → [Reset] → [Clear Lamp Hours] to reset the lamp usage hours.
NOTE: When the lamp exceeds 2100* hours (up to 3100* hours in Eco mode) of service, the projector cannot turn on and the
menu is not displayed.
If this happens, press the HELP button on the remote control for ten seconds to reset the lamp clock back to zero.
When the lamp time clock is reset to zero, the LAMP indicator goes out.
* VT58 and VT48: 3100 hours (up to 4100 hours in Eco mode).
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