| 摘要 |
<p>PURPOSE:To eliminate need to prepare a power source specially by a user, to eliminate the trouble of wiring, etc., to easily conform to the specifications of external input equipment, and to make a transmission ratio constant and obtain stable performance by incorporating plural fixed power sources which are generally used. CONSTITUTION:This programmable controller is equipped with an input circuit that has plural signal input terminals 4 for receiving signals from plural external input equipments, and a power supply terminal 8 and a ground terminal 5 which are exposed to the outside to receive electric power from outside; and a constant current element 13 is arranged between the power supply terminal 8 or ground terminal 5 and the signal input terminals 4. The range of a source voltage supplied to the input circuit can be made wide and various external input equipments can be connected without altering an internal circuit.</p> |
