F32120 — Encoder 2: Encoder power supply fault

F32120 tells you the drive has detected a fault in the power supply of encoder 2. The list manuals print it under slightly different titles — «Encoder 2: Encoder power supply fault» and «Encoder 2: Power supply voltage fault» — but describe the same condition and the same remedies. The drive writes the cause into the fault value r0949, which is interpreted as a binary number: each set bit names one supply problem, from an undervoltage on the sense line to a hardware fault at the EnDat connection. Depending on how the drive is configured, the same monitoring can also be output as an alarm (A) or with no reaction (N).

• An encoder power supply fault was detected on encoder 2; the binary fault value in r0949 shows which condition tripped the monitoring (see the bit list below).
• If the encoder cables 6FX2002-2EQ00-.... and 6FX2002-2CH00-.... are interchanged, this can result in the encoder being destroyed because the pins of the operating voltage are reversed.

1. Read the fault value in r0949 as a binary number and note which bit is set.
2. Bit 0 set (undervoltage on the sense line): check that the correct encoder cable is connected, check the plug connections of the encoder cable, and on an SMC30 check the parameterization in p0404.22.
3. Bit 1, 2 or 3 set (overcurrent in the encoder power supply or on the resolver excitation cables): check that the correct encoder cable is connected, then replace the encoder or the encoder cable.
4. Bit 4 set (the 24 V power supply through the Power Module (PM) is overloaded): the manuals list no separate remedy for this bit.
5. Bit 5 set (overcurrent at the EnDat connection of the converter): check that the measuring unit is correctly connected at the converter; replace the measuring unit or the cable to the measuring unit.
6. Bit 6 or 7 set (overvoltage or hardware fault at the EnDat connection): replace the defective EnDat 2.2 converter.

The message value is the fault cause. The drive stores it in r0949 and it must be interpreted binary:

• Bit 0: undervoltage condition on the sense line.
• Bit 1: overcurrent condition for the encoder power supply.
• Bit 2: overcurrent condition for encoder power supply on cable resolver excitation negative.
• Bit 3: overcurrent condition for encoder power supply on cable resolver excitation positive.
• Bit 4: the 24 V power supply through the Power Module (PM) is overloaded.
• Bit 5: overcurrent at the EnDat connection of the converter.
• Bit 6: overvoltage at the EnDat connection of the converter.
• Bit 7: hardware fault at the EnDat connection of the converter.

• r0949 — fault value of this message: read it as a binary number; the set bits identify which encoder 2 supply fault occurred.
• p0404.22 — effective encoder configuration: when bit 0 (sense-line undervoltage) is set and an SMC30 is connected, check this parameterization.

The fault is acknowledged with pulse inhibit (PULSE INHIBIT): bring the drive into the pulse-inhibited state, acknowledge F32120 and then restart the drive. Where the same condition is configured as an alarm (A) or with no reaction (N), there is neither reaction nor acknowledgement (NONE).