| 摘要 |
PURPOSE:To execute a good control in the whole area of a temperature program, in case of a program control of heat treatment of a metal, etc., by constituting so that a proportional band is automatically varied and operated by a set value. CONSTITUTION:As to a value of a proportional band PB, PB1 in a high set value SV1 is set by a key 41 of P1, and PB2 in a low set value SV2 is set by a key 42 of P2. In this state, a value of a proportional band PBx in an optional set value SVx is derived by a calculating equation of PBx= (pb1-PB2).(SVx- SV1) /(SV1-SV2)+PB2...(1). A microprocessor 7 converts an input signal from a detector, to a digital value by an A/D converter 8 at every constant interval of time, inputs it through an internal bus 9, also PID-operates a deviation against a set value which is set in advance from a keyboard 4 and is held in a memory 6, and this operation result is sent to a D/A converter 5 through the internal bus 9 from the microprocessor 7, is converted to an analog value, outputs an operating signal 2 and controls it. |
