Okuma OSP 5000, Электротехническое обслуживание, Учебное пособие

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Okuma America Corporation
DIAGNOSTICS DIAGNOSTICS
DIAGNOSTICS DIAGNOSTICS
DIAGNOSTICS
Rev. 8-21-01
ALARMS
The OSP control is designed to make the most of its built-in computer capabilities. The self-
diagnostics function of the control constantly monitors the internal conditions of the CNC. The
control also monitors external conditions, such as machine conditions, program data, and opera-
tor input conditions. When a fault is detected, the control displays an alarm or error message.
Depending on the severity of the alarm, the machine can be brought to a complete stop immedi-
ately or the work process can be completed and then the machine will stop.
When an alarm message is displayed, the alarm light on the NC operation panel turns on and the
message is displayed on the 2nd line of the CRT.
CPU alarms are displayed on the central portion of the CRT. A CPU alarm will display an
access address. This access address indicates which board the CPU was trying to access when
the alarm occurred. Of the 8 digits displayed, only the six digits from the right are used when
looking up which board was being accessed. It is important to know what type of main board is
in the control rack (MB, MBII, MBIIA, or MBIIB) when checking the access address tables.
An error message is usually a warning that the operator has entered wrong data. This message is
displayed on lines 19 to 22 on the CRT and the alarm light does not turn on. An error message is
usually cleared as soon as another function is performed.
Machining centers also have a diagnostic message display function for ATC and APC operation.
These message displays can be accessed by pressing the EXTEND (F8) function key and then
the DIAGNOSIS (F5) function key. A description of these messages can be found in the Mainte-
nance manual of the machine in question.
When deciphering what an alarm means, it is useful to know how to count in Hexadecimal. It is
also useful to know how to convert from “hex” to binary or octal. The following is a brief
explanation of the different numbering systems used in computer technology.
In decimal, each position to the left of the decimal point indicates an increased power of ten. In
binary, base two, each place to the left signifies an increased power of two. The binary system
represents all numbers as strings of the digits one and zero. Either digit represents a bit which is
the smallest unit of information in a computer system. A nibble is four bits and a byte is eight
bits. A word is two bytes (16 bits) and a long word is two words (32 bits). Any one of these
units can occupy a single storage location and can be processed as a single unit by the computer.
Hexadecimal is a base 16 numbering system. One Hexadecimal number represents four bits.
Octal is a base eight numbering system. One Octal number represents three bits.