Convo Inverter Cvfs1 Manual Link -

: Upon powering on, the panel typically displays 0.0 (output frequency). Returning to the original display after parameter changes can be done by selecting parameter d-00 and clicking SET or long-pressing the SET key for 3 seconds.

The Convo CVF-S1 is a single-phase, small-power, high-performance frequency inverter (also known as a Variable Frequency Drive or VFD). It was designed for applications requiring precise motor speed control in industrial settings. Originally manufactured by Shenzhen Convo Electric Technologies Co., Ltd., this inverter later became part of the Bosch Rexroth product line under the model number FSCS01. convo inverter cvfs1 manual link

If you can tell me the you are seeing or the motor task you are trying to automate (e.g., constant speed, external potentiometer control), I can give you the exact parameter numbers to change. : Upon powering on, the panel typically displays 0

(Includes various Convo series) Key Sections of the CVFS1 Manual It was designed for applications requiring precise motor

https://www.manualslib.com/manual/1287757/Convo-Cvfs1.html

: Digital signal common port operating at zero potential.

The primary input voltage supply has dropped significantly below the nominal threshold.