| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that, a conventional LED illumination device cannot be lighted on until repaired/exchanged if the illumination device is lighted off because of a power source failure since one-system supply using an AC power source is adopted, efficiency is low since it is necessary to perform repair/exchange through a routine maintenance in the case where the LED illumination device is enabled to be continuously lighted on even in the case of power source failure by power supply using a plurality of systems, and much cost and time may be required since it is necessary to perform high-place work and signboard disassembly in the case where any failure occurs in a power source of an LED illumination device within a conventional signboard lamp.SOLUTION: In a non-lighting preventive backup power supply system for a signboard lamp, at least two DC power supply circuit units are connected at a cathode side of the diode within each of the DC power supply circuit units. Each DC power supply circuit unit includes: an AC cut-off switch; a DC power source connected to the AC cut-off switch; a diode in which an anode is connected to (+) side output of the DC power source; a relay in which (+) side control input is connected to (+) side output of the DC power source and the anode of the diode; and failure notification contact output of the relay. |
