108

Identify the exact line number where alarm 108 occurred by checking the control display or alarm history.

Examine the macro program at that line for division operations (/ symbol) or formulas containing division, noting which variable is the divisor.

Trace backward through the program to find where the divisor variable is assigned or calculated, checking for conditions that could result in zero.

Add conditional logic (IF statements) to check if the divisor is zero before division, or initialize the variable with a non-zero default value if appropriate for the application.

Verify that changing the variable initialization does not affect other calculations or tool offsets in the macro program.

Review the macro line causing the alarm and identify any calculated expressions used as divisors (e.g., [#1-#2] or [#3*COS[#4]]).

Check current values of all variables involved in the divisor calculation using the macro variable display screen (OFFSET or MACRO menu depending on control model).

Verify input parameters from the calling program or operator input that feed into these variables, looking for values that make the expression equal zero.

Implement range checking with IF-THEN statements before the division to validate inputs are within expected ranges, or add a small epsilon value to prevent exact zero results.

Adding epsilon values may affect dimensional accuracy; ensure tolerances remain within part specifications.

Check if the macro uses system variables (e.g., #5001-#5999 for tool offsets, #2001-#2999 for work coordinates) as divisors.

Access the OFFSET SETTING display and verify that all tool geometry, wear offsets, and work coordinate systems referenced in the macro contain valid non-zero values where expected.

Do not randomly enter values into offset registers without proper tool measurement or coordinate system setup.

Review custom parameters (setting numbers) used in the macro to ensure they have been initialized in the parameter table with appropriate values.

Add error handling in the macro to check system variable values before use, displaying a custom message (POPEN/PCLOS or #3000 alarm) to guide the operator to set the missing value.