| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of preventing the welding of relay contacts due to residual oscillation without causing a discharge failure in the high-temperature atmosphere when normal lighting is switched to emergency lighting. SOLUTION: Normal lighting is switched to emergency lighting via relay contacts Ry-a, Ry-b, Ry-c, Ry-d. A power failure detecting circuit 3 detects the presence or absence of a commercial power supply Vac. When the commercial power supply Vac is normal, the circuit 3 switches the relay contacts Ry-a, Ry-b, Ry-c, Ry-d to the normal inverter side. When the commercial power supply Vac is interrupted, the circuit 3 switches the relay contact Ry-c on the preheating capacitor C2 side to the emergency lighting inverter INV2 side, then it switches the remaining three relay contacts to the emergency lighting inverter INV2 side to connect a discharge lamp La. |
