Title:
PRESERVING CONTROL METHOD OF CONTROL DATA
Document Type and Number:
Japanese Patent JPS5998211
Kind Code:
A
Abstract:
PURPOSE:To economize a memory and to facilitate data analysis by using the sampling time of the most minor sampler in the near past of the trouble occurrence time as the start period of gathering of trouble data and using the sampling time of a sampler of a memory in a longer-cycle minor loop in the farther past. CONSTITUTION:In a sampling operation 41, a minor current controller and a major speed control operating device are provided. Since the sampling cycle of this minor loop is shorter than that of the major loop, an operation cycle TACK of a sampler of the current control operation is 1/3-1/5 times as long as an operation cycle TASR of a sampler of the speed control operation. A frequency divider generates a timing which makes the cycle TASR shorter and gives it to a sampler R'TACR of a memory 44. Thus, cycles TASR and R' TACR of samplers of memories 43 and 44 are longer than the cycle TACR of the sampler of a memory 42. As a result, the most minort sampler is used in the near past of the trouble occurrence time, and the sampler of the memory in a longer-cycle minor loop is used in the farther past.
Inventors:
TACHIKAWA MAKOTO
TAKAHASHI JIYUNICHI
TAKAHASHI JIYUNICHI
Application Number:
JP20609682A
Publication Date:
June 06, 1984
Filing Date:
November 26, 1982
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G05B23/02; G05B21/02; (IPC1-7): G05B23/02
Attorney, Agent or Firm:
Katsuo Ogawa