Delta bF fault code meaning
Delta / bF
Series: C2000 Plus
Braking transistor error detected
AC motor drive
Meaning: The AC motor drive has detected a braking transistor error (only on models with a built-in braking transistor).
Possible causes
- Hardware fault
- 1. Press the RESET key. If bF is still displayed, return the unit to the manufacturer for repair.
- 2. Due to an internal circuit error in the AC motor drive, first disconnect the power supply, then use a multimeter to check for a short circuit between the following terminals:
- Malfunction due to interference
- Incorrect braking resistor selection
- Incorrect braking resistor wiring
Source: C2000 Plus Series User Manual (DELTA_IA-MDS_C2000 Plus_UM_TC_20250522) P421
Series: C2000-R, VFD-ED
Braking transistor error detected
AC motor drive
Meaning:
Possible causes
Source: C2000-R User Manual P218; VFD-ED Series User Manual (DELTA_IA-MDS_VFD-ED_UM_SC_20170315) P126
Series: CFP2000, CH2000, CP2000, DPD-K
Braking transistor error detected
AC motor drive
Meaning: The AC motor drive detected a braking transistor error (only on models with a built-in braking transistor).
Possible causes
- Hardware fault
- 1. Press the RESET key. If bF is still displayed, return the unit to the manufacturer for repair.
- 2. Due to an internal circuit error in the AC motor drive, first disconnect the power supply, then use a multimeter to check for a short circuit between the following terminals:
- Malfunction due to interference
- Incorrect braking resistor selection
- Incorrect braking resistor wiring
Source: CFP2000 Series User Manual (DELTA_IA-MDS_CFP2000_UM_SC_20250731) P284; CH2000 Series User Manual (DELTA_IA-MDS_CH2000_UM_SC_20251030) P382; CP2000 Series User Manual (DELTA_IA-MDS_CP2000_UM_SC_20250704) P392; DPD-K Series User Manual (DPD-K user manual_20211224) P317
Series: CT2000
Braking transistor error
AC motor drive
Meaning:
Possible causes
Source: CT2000 Series User Manual (DELTA_IA-MDS_CT2000_UM_SC_20250522) P248
Series: VFD-DD, VFD-VE
Brake transistor error
AC motor drive
Meaning:
Possible causes
Source: VFD-DD (Ver. F, S, T & V ) (DELTA_IA-MDS_VFD-DD_UM_TC_20170609) P36; Delta VFD-VE Manual P66