| 摘要 |
PROBLEM TO BE SOLVED: To obtain a key telephone set which reduces the maximum current consumption in private branch exchange as a whole and close not require restrictions on use. SOLUTION: In this key telephone set, an LED 106 displays the line use state or a function like a terminating function, and a display device current supply circuit 103 for rated use used at the time of driving in the normal mode and a display device current supply circuit 104 for power saving used at the time of driving in the power saving mode provided, and these two types of display device current supply circuits are switched by the selection of a circuit changeover switch 105. With respect to this switching, a current threshold to be a reference for selection is stored in a threshold current storage part 102, and a current consumption monitor part 107 monitors the current consumption of the telephone set, and a current comparison part 101 compares the monitored current consumption value with the current threshold stored in the threshold current storage part 102, and if the current consumption value is larger than the threshold, the circuit changeover switch selects the display device current supply circuit for power saving to which a smaller supply current value is set. |
