Siemens SINAMICS V90, SIMOTICS S-1FL6 Error A52901: Braking resistor reaches alarm threshold

Industrial motor drive · taken from the manufacturer’s manual, pages cited

Fault codeA52901

Braking resistor reaches alarm threshold when the braking resistor’s heat capacity has reached its capacity threshold. The manual's first action is: “Change the external braking resistor.”

Model
Siemens SINAMICS V90, SIMOTICS S-1FL6
Display shows
Braking resistor reaches alarm threshold (A52901)
Type
Fault code
Source
Manual p. 312

What A52901 means

Braking resistor reaches alarm threshold p. 312

Common causes

  • The heat capacity reaches the threshold (p29005) of the braking resistor capacity. p. 312

Safety warnings — read before you start

  • DANGERGeneral Safety Instructions. Qualified Personnel The product/system described in this documentation may be operated only by personnel qualified for the specific task in accordance with the relevant documentation, in particular its warning notices and safety instructions. p. 2
  • WARNINGRisk of Electric Shock and Fire. Risk of electric shock and fire from supply networks with an excessively low impedance Excessively high short-circuit currents can lead to the protective devices not being able to interrupt these short-circuit currents and being destroyed, and thus causing electric shock or a fire. p. 12
  • WARNINGElectric Shock if No Ground Connection. Electric shock if there is no ground connection For missing or incorrectly implemented protective conductor connection for devices with protection class I, high voltages can be present at open, exposed parts, which when touched, can result in death or severe injury. p. 12
  • WARNINGElectric Shock Due to Unsuitable Power Supply. Electric shock due to connection to an unsuitable power supply When equipment is connected to an unsuitable power supply, exposed components may carry a hazardous voltage that might result in serious injury or death. p. 12

What to do

  1. Change the external braking resistor. p. 312
  2. Increase deceleration time. p. 312

If A52901 is still not resolved

  • Contact service / dealer for assistance p. 2
    “Qualified Personnel The product/system described in this documentation may be operated only by personnel qualified for the specific task in accordance with the relevant documentation, in particular its warning notices and safety instructions.”
  • Contact service / dealer for assistance p. 13
    “NOTICE Property damage due to loose power connections Insufficient tightening torques or vibration can result in loose power connections. This can result in damage due to fire, device defects or malfunctions.”

This page summarises what the manufacturer’s manual says about A52901; each statement links to the page it comes from, and quoted lines are copied word for word. It is not a substitute for the manual or for a qualified installer. ManualLib is not affiliated with Siemens. Found a mistake? Report an error.