What causes Siemens SINUMERIK alarm 12587?

Unsupported operator or function used in motion synchronous action logic that doesn't match the permissible operator list. Real-time variable operation attempting to use prohibited functions like string operations, array indexing, or type conversion in sync context. Incorrect syntax or spelling of a permissible operator causing system to fail recognition. Logic operation attempted on incompatible data types within motion synchronous action block.

How do I fix Siemens SINUMERIK alarm 12587?

1. Review the NC program at the specified channel and block location; identify the operator/function at line %3 that triggered the alarm 2. Cross-reference the used operator/function against the permissible list: comparison (==, >=, , ), arithmetic (+, -, *, /, DIV, MOD), logical (AND, OR, XOR, NOT), bitwise (B_AND, B_OR, B_XOR, B_NOT), and mathematical (SIN, COS, TAN, ATAN2, SQRT, POT, TRUNC, ROUND, AB) 3. Replace the non-permissible operator/function with an equivalent permissible one or restructure the logic expression to comply with motion synchronous action constraints 4. Verify data types of operands are real-time compatible; ensure variables used in the synchronous action are declared correctly and are numeric types 5. Recompile or reload the NC program and test the modified block to confirm alarm clears

Siemens SINUMERIK codes

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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 20-45 minutes

Alarm 12587

Siemens 840D 12587 - Channel block motion synchronous action: operation/function

The specified function / operator is not permissible for logic operations of real-time variables in motion synchronous actions. The following operators/functions are permissible: - == >= <= > < <> + - * / - DIV MOD - AND OR XOR NOT - B_AND B_OR B_XOR B_NOT - SIN COS TAN ATAN2 SQRT POT TRUNC ROUND AB

Siemens SINUMERIKServo/AxisIntermediate20-45 minutes

12587

Siemens 840D 12587 - Channel block motion synchronous action: operation/function

Channel block motion synchronous action: operation/function

Safety

Refer to Siemens documentation
Ensure qualified technician performs repairs

Common Causes

Unsupported operator or function used in motion synchronous action logic that doesn't match the permissible operator list
Real-time variable operation attempting to use prohibited functions like string operations, array indexing, or type conversion in sync context
Incorrect syntax or spelling of a permissible operator causing system to fail recognition
Logic operation attempted on incompatible data types within motion synchronous action block

Troubleshooting Steps

1Review the NC program at the specified channel and block location; identify the operator/function at line %3 that triggered the alarm
2Cross-reference the used operator/function against the permissible list: comparison (==, >=, <=, >, <, <>), arithmetic (+, -, *, /, DIV, MOD), logical (AND, OR, XOR, NOT), bitwise (B_AND, B_OR, B_XOR, B_NOT), and mathematical (SIN, COS, TAN, ATAN2, SQRT, POT, TRUNC, ROUND, AB)
3Replace the non-permissible operator/function with an equivalent permissible one or restructure the logic expression to comply with motion synchronous action constraints
4Verify data types of operands are real-time compatible; ensure variables used in the synchronous action are declared correctly and are numeric types
5Recompile or reload the NC program and test the modified block to confirm alarm clears

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