F07935 — Drive: Incorrect motor holding brake configuration

F07935 reports that the configuration of the motor holding brake does not match the brake the drive has detected — for example, a brake that is connected while brake control is switched off in p1215, or settings for a parallel connection or the Safe Brake Adapter (SBA) that conflict with the Safe Brake Control (SBC) function. The manuals also list the same condition as an entry with no reaction (N); which of the two variants the drive outputs depends on its configuration.

The manual names a single cause: an incorrect motor holding brake configuration was detected. What is actually wrong is separated into the numbered cases listed under fault value — each value covers a different combination of connected brake, p1215 setting, SBA interconnection, parallel-connection data and SBC function.

1. Fault value 0: no remedy required.
2. Fault value 1: if required, change the motor holding brake configuration (p1215 = 1, 2). If this fault value occurs unexpectedly, check the motor connections to rule out that they have been interchanged.
3. Fault value 11: on a parallel connection, connect only one motor holding brake.
4. Fault value 12: check the setting of the power unit data set for the parallel connection (p7015).
5. Fault value 13: before p7015 is changed, deactivate the Safe Brake Control function (SBC) via p9602.
6. Fault value 14: check (r9771.14) whether the power unit supports brake control for a parallel connection; look for a DRIVE-CLiQ communication error between the Control Unit and the affected power unit and, if required, run a diagnostics routine for the faults identified.

The drive writes the fault value into the message value (%1) and into r0949; interpret it as a decimal number:

• 0 — a motor holding brake is present although brake control has not been configured (p1215 = 0). At first commissioning this value is also output when the brake control was set to motor holding brake the same as sequence control (p1215 = 1), when the interconnection p9621 = r9872.3 was made for a chassis unit with Safe Brake Adapter (SBA), or when the power unit carrying the motor holding brake was entered in p7015 for a parallel connection.
• 1 — a motor holding brake is present while the configuration still reads No motor holding brake available (p1215 = 0), i.e. brake control was never set up for the connected brake.
• 11 — identification found more than one motor holding brake on a parallel connection.
• 12 — for a parallel connection, p0121 does not contain a valid component number for the power unit data set entered in p7015.
• 13 — with Safe Brake Control (SBC) activated, an attempt was made to change p7015.
• 14 — for a parallel connection, the power units set in p7015 cannot be addressed.

• r0949 — holds the fault value of this entry; read it as a decimal number to identify which brake configuration case applies.
• p1215 — the motor holding brake configuration: with fault value 1, set it to 1 or 2 if the connected brake should be controlled; p1215 = 0 means no brake control is configured (fault values 0 and 1).
• p7015 — power unit data set for the holding brake in a parallel connection: enter or check it here (fault values 0, 12, 14) and change it only with SBC deactivated (fault value 13).
• p0121 — power unit component number: with fault value 12, verify it holds a valid number for the power unit data set set in p7015.
• p9602 — SI enable Safe Brake Control (Control Unit): use it to deactivate SBC before p7015 is changed (fault value 13).
• r9771 — SI common functions (Control Unit): bit 14 shows whether the power unit supports brake control for a parallel connection (fault value 14).
• p9621 — BI: SI Safe Brake Adapter signal source (Control Unit): interconnecting it as p9621 = r9872.3 for a chassis unit with SBA is one of the first-commissioning situations reported as fault value 0.

The entry initiates no automatic OFF1, OFF2 or OFF3, so the drive is not switched off when it appears. Correct the setting that the fault value identifies and then acknowledge the fault immediately — the manual specifies immediate acknowledgement for this code. No further restart steps are described beyond correcting the configuration.