Siemens SINUMERIK codes
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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 20-45 minutes

Alarm 12220

Siemens 840D 12220 - Channel block binary constant in string too long

When initializing or allocating the value of a variable of type STRING more than 8 bits have been found as binary constant. DEF STRING[8] OTTO = "ABC'H55''B000011111'DEF"

Siemens SINUMERIKServo/AxisIntermediate20-45 minutes

12220

Siemens 840D 12220 - Channel block binary constant in string too long

Channel block binary constant in string too long

When initializing or allocating the value of a variable of type STRING more than 8 bits have been found as binary constant. DEF STRING[8] OTTO = "ABC'H55''B000011111'DEF"

Safety

  • Refer to Siemens documentation
  • Ensure qualified technician performs repairs

Common Causes

  • Binary constant embedded in string exceeds 8-bit boundary (0-255 decimal range)
  • Multiple binary constants in single string declaration without proper separation or truncation
  • Incorrect syntax for binary constant notation using single quotes
  • String variable declared with insufficient length for embedded binary data
  • Copy-paste error from external source with malformed binary constant format

Troubleshooting Steps

  1. 1Review the string declaration in Channel %1, Block %2 and identify the binary constant %3 that exceeds 8 bits
  2. 2Verify binary constant uses correct syntax with single quotes and contains only 8 bits maximum (B00000000 through B11111111)
  3. 3If binary value exceeds 8 bits, split into multiple 8-bit constants or use hexadecimal notation (H00 through HFF) instead
  4. 4Confirm STRING variable length declaration matches actual character content including binary representations
  5. 5Recompile or reinitialize the program after correcting the binary constant length and retest the channel initialization

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