Chinese BSW200 pan issue

[Nicktaylor]

Basically the unit is losing registration , sometime on startup and sometimes part way through a show. Restarting usually gets it running right. I imagine its a detector that is intermittently not read correctly. Any ideas please?

[DrV]

The other likely fault is that it is missing steps. This could be because a drive belt is too tight (or very loose) or a stiff bearing or it could an electronic issue which is causing the current through the stepper motor to be too low. Or, as you said it could be an intermittent sensor.

[niclights]

Or dirt on the encoder?

[pmiller056]

Check the voltages from the power supply are correct and stay correct during use. I've had a similar fault on a cheap moving head lamp - when the power supply was heavily loaded doing fast moves with all LED elements on at full brightness, it missed steps and then totally lost the plot.... A replacement PSU fixed the problem.

[Richard CSL]

A cracked stepper feed wire can cause loss of steps, although if its pan this motor does not move, unless electronics is in the arm. dirty encoder can be a common issue