Siemens alarm 14820: Channel %1 block %2 negative value for maximum spindle speed programmed with constant cutting speed

What it means

While constant cutting speed (G96) is active, a negative value was programmed for the maximum spindle speed limit (LIMS). The limit clamps the G96-computed speed as diameter changes and must be positive. Reprogram LIMS with a valid positive speed.

Likely causes

• LIMS word entered negative
• LIMS assigned from a variable/expression that evaluated negative
• Confusion between rpm and m/min units when entering the limit