F07753 — Drive: No valid pressure actual value available

F07753 is raised when a closed-loop function the drive has switched on cannot obtain the pressure feedback it requires. Two groups of functions are involved: the "force controller", "force limiting" and "stiction compensation", which all need the two pressure actual values A and B, and the system pressure adaptation of the speed controller, which needs a system pressure measured value (r0069). If the corresponding sensor supplies no valid value, the drive cannot execute the function and signals this fault. Depending on how the drive is configured, the same condition can also be output as an alarm or without any automatic reaction.

• One of the functions "force controller", "force limiting" or "stiction compensation" is activated (p1400), and at least one of the two pressure sensors required for pressure actual value A or B is not supplying a valid value — both pressure actual values A and B are required for these functions.
• The system pressure adaptation function of the speed controller is activated (p1400.15 = 1), and no system pressure measured value (r0069) is available — a system pressure measured value is required for this function.

1. Check the pressure sensors and their wiring for pressure actual values A and B at X241 or X242.
2. Check the offset correction values for pressure actual values A and B (p0241, p0243).
3. If required, deselect the function "force controller", "force limiting" or "stiction compensation" (p1400).

• p1400 (Closed-loop control configuration): shows whether "force controller", "force limiting" or "stiction compensation" is activated, and whether bit 15 = 1 has switched on the system pressure adaptation of the speed controller — this is also where the function is deselected if the pressure feedback cannot be restored.
• r0069 (CO: System pressure actual value): check here whether a system pressure measured value is present at all for the system pressure adaptation function.
• p0241 (Pressure sensor A offset correction): check the offset correction value belonging to pressure actual value A.
• p0243 (Pressure sensor B offset correction): check the offset correction value belonging to pressure actual value B.

After the cause has been corrected, the fault is acknowledged and the drive accepts the acknowledgment immediately — no waiting time applies — so the drive can be restarted as soon as a valid pressure actual value is available again.