JPS63114594A - Trace back method for variable speed driving device - Google Patents

Abstract

PURPOSE:To clarify operating conditions before and after generating a trouble and analyze the trouble highly accurately and easily, by a method wherein memorized data are transferred to a non-volatile memory cell to store them upon generating the trouble. CONSTITUTION:A RAM 8 rewrites the data of a data cell into updated data one after another and stores the data of (n) times immediately before the rewriting. When a trouble is generated, the RAM 8 effects the sampling of the data of (n-m) times (0<=m<=n) after generating the trouble. When the data before and after generating the trouble are recorded, the sampling is stopped and the data are transferred to a non-volatile memory cell 9. As a result, (m) pieces of data before generating the trouble and (n-m) pieces of data after generating the trouble are stored in the non-volatile memory cell 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a traceback method for variable speed drive devices used in machine tool drives, FA systems, and the like.

[Conventional technology]

This type of variable speed drive device is digitally controlled! ! Advances in technology have led to increasingly sophisticated functionality and performance. Along with this, the mechanisms of failure occurrence have become diverse, making it difficult to investigate the cause of failure occurrence.

As a countermeasure against this problem, conventionally, a traceback function has been used which records the operating state on the RAM and reproduces the operating state at the time of the failure.

[Problem that the invention seeks to solve]

However, with this method, all records are erased when the power is cut off, so failure investigation can only be done at the location where the device is being used. was impossible. Further, the above method cannot be applied to a system in which electricity is cut off in the event of a failure.

The present invention was made in view of these conventional problems, and even if the power is cut off once, when the power is turned on again, the operating conditions before and after the failure occur can be reproduced, making it easy to investigate the cause of the failure. The purpose is to

[Means for solving problems]

In order to achieve this objective, the traceback method of the present invention is applied to a data-rewritable RAM in a variable speed drive device such as an inverter drive or a servo drive.
and a non-volatile memory element, variables indicating operating conditions such as rotational speed, frequency, current, etc., and logic signals indicating operating conditions such as input/output signals are sampled at a period T, and new n times of data are always stored in the RAM. Write above, when a failure occurs,
Data for m times before failure occurrence and n −m (n>
The method is characterized in that the data of m) is transferred to and recorded in the non-random storage element.

[Effect]

In the traceback method of the present invention, in a digital control circuit using a microprocessor of a variable speed drive device, storage elements such as RAM (hereinafter referred to as rRAMJ) for rewriting data, EEPROM, N
Using an electrically rewritable ephemeral memory element such as VRAM (hereinafter referred to as rEEPROMJ), data on the operating status before and after the occurrence of a fault that is stored in the RAM is transferred to and recorded in the EEPROM after the fault occurs. . This results in
Even if the power is turned off, the data recorded in the EEFROM is retained. After the power is turned on again, these data can be read and displayed.

(Example) Hereinafter, the present invention will be specifically described based on an example shown in the drawings. FIG. 1 is a schematic diagram of a variable speed drive device having the functions of the present invention.

In FIG. 1, 1 is an inverter and 2 is a motor.

The inverter 10 control circuit section 3 includes an input/output signal interface 110 section 4, an inverter 1, and a motor 2.
Sensor part 5 that detects voltage, current, temperature 9 rotation speed, etc.
, CPU, ROM.

It is composed of an inverter control section 6 consisting of a RAM, etc., and a display section 7 that displays data. RAM B and EEF ROM 9 used for traceback are included in the inverter control section 6, and the data is displayed on the display section 7.
In the figure, 10 represents a pulse generator that detects the rotational position of the motor 2, and 11 represents a commercial '@ source.

The traceback data includes data necessary for failure analysis, that is, variable data such as voltage, current, temperature, and number of revolutions, and logical signal data such as operating status and input/output signals.

These traceback data are sampled at a period Ts+s and sequentially recorded in n data cells set in the RAM 8. When n samplings are completed, fi+
From the first time, the contents of the data cell are rewritten with new data. In other words, the data recorded in the data cell,
The relationship between sampling times is as follows: 1st data cell □ (nxk+1) times 2nd data cell □ (nxk+2) times n-th data cell □
This is the (nXk+n)th time. However, k is k-1, 2
,..., and so on.

In this way, during normal operation, the data in the data cells is rewritten one after another with new data, and the data for the previous n times are recorded.

When a failure occurs, data is then sampled n−m times (0≦m≦n). After recording the data before and after the occurrence of a failure, sampling is stopped and the data is transferred to the EEFROM. That is, as shown in Fig. 2, m pieces of data before the failure occurrence and nm pieces of data after the failure occurrence are
Record in EF ROM. The chronological order of the data to be recorded can be clarified using pointers. Also EEF
Since the data recorded in the ROM is non-volatile, the data is not erased by turning the power on or off, and can be rewritten only by entering a password.

〔Effect of the invention〕

As explained above, in the present invention, a RAM and a non-volatile memory element in which data can be rewritten are used, and when a failure occurs, the stored data is transferred to the non-volatile memory element and recorded. The operating status at the time of failure is displayed after the power is turned off and turned on again. Therefore, the operating status before and after the occurrence of a failure becomes clear, and recorded data can be retained even if the power is cut off. Therefore, failure analysis at a service center or the like can be performed easily and with high accuracy.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a variable speed drive device having the functions of the present invention, and FIG. 2 is a timing chart of recording traceback data when a failure occurs. 1; Impark 2: Motor 3: Control circuit section 4: 110 section 5: Sensor section 6: Inverter system 2 TJ section 7:
Display section 8: RAM M9: E E P
ROM 10: Pulse generator 11: Commercial power supply

Claims (1)

[Claims] 1. RAM that allows data to be rewritten in variable speed drive devices such as inverter drives and servo drives
and a non-volatile memory element, variables indicating the operating state such as rotational speed, frequency, and current, and logical signals indicating the operating state such as input/output signals are sampled at a cycle T, and new n times of data are always stored in the RAM. When a failure occurs,
Data for m times before failure occurrence and nm after failure occurrence (n>m)
A traceback method for a variable speed drive device, characterized in that the data is transferred to the nonvolatile storage element and recorded.