F07950 — Drive: Incorrect motor parameter

F07950 reports that the motor data in the drive does not fit what was commissioned: the motor parameters were entered incorrectly during commissioning — the manual's own example is p0300 = 0, i.e. no motor selected. The drive stores the number of the parameter involved in r0949, to be interpreted as a decimal number, and the same parameter number appears as the message value. Depending on how the drive is configured, the same condition can also be output as alarm A07950.

• The motor parameters were entered incorrectly while commissioning — the manual's example is p0300 = 0, i.e. no motor selected.
• The braking resistor has still not been parameterized, and commissioning cannot be completed — these two causes are described in the S120, S150, G130 and G150 manuals; the G120 and G120XA manuals name only the incorrect entry during commissioning.
• Fault value 300: for the selected control mode, the motor type is not supported (see the decoding below).
• Fault value 307: the rated motor data could be incorrect (see the decoding below).

1. Read the fault value in r0949 as a decimal number — it names the parameter number involved.
2. Compare the motor data with the rating plate data and if required, correct.
3. For fault value 300: operate a motor type supported by the selected control mode.

• The fault value in r0949, interpreted as a decimal number, is the parameter number involved; the message value of the message carries the same parameter number.
• 300: for the selected control mode, the motor type is not supported. On VECTOR drive objects the manual spells out that the synchronous-reluctance motor is not operated in the closed-loop speed/torque control mode; in the other entries the value 300 is marked for the CU250S-2.
• 307: the following motor parameters could be incorrect: p0304, p0305, p0307, p0308, p0309.

• p0300 (Motor type selection): the manual's example of a wrong entry for this fault is p0300 = 0, i.e. no motor — check that the selected motor type matches the motor actually connected.
• r0949 (Fault value): read it as a decimal number to see which parameter number raised F07950.
• p0304 (Rated motor voltage): flagged by fault value 307 as possibly incorrect — compare with the rating plate.
• p0305 (Rated motor current): flagged by fault value 307 as possibly incorrect — compare with the rating plate.
• p0307 (Rated motor power): flagged by fault value 307 as possibly incorrect — compare with the rating plate.
• p0308 (Rated motor power factor): flagged by fault value 307 as possibly incorrect — compare with the rating plate.
• p0309 (Rated motor efficiency): flagged by fault value 307 as possibly incorrect — compare with the rating plate.

The message is acknowledged immediately — no power-down and no special acknowledgment sequence are required, and because the drive takes no tripping action on this message, the practical step is simply to correct the parameter values. Where the drive is configured to output the condition as alarm A07950 instead, it triggers no reaction there either and needs no acknowledgment.