| 摘要 |
PROBLEM TO BE SOLVED: To increase the number of multi-speed frequency without increasing the number of terminals by determining preset frequency corresponding to a digital value based on a relation between analog command input and preset frequency. SOLUTION: A function presetting means 12a writes, in a storage means 13a, a relation between an analog command input value (0 to 10V) inputted by an inputting device 11 and 5-speed frequency (1-speed frequency, 2-speed frequency, 3-speed frequency, 4-speed frequency, and 5-speed frequency), and multi-speed frequency. An A/D converter 55 converts an analog command inputted from an analog command input terminal 4 into a digital value. An analog command-frequency converting means 14a determines preset frequency for a digital value converted by the A/D converter 55 based on a relation between a pre-determined analog command input and preset frequency. The number of divisions of the analog command input is not limited to 5. If it is lower than the resolution of the A/D converter 55, it is possible to conduct multi-speed operation whose number of divisions is more. |
