Hello John and everyone else,
It may be that the power supply of the heater or the temperature controller has a defect. But then he does not heat or he heat constantly.
I used this power supply to power an electric motor (<4A). It has turned off after some time and after a few minutes without power it then worked again. Then I connected a resistive load and let a current of 4.7 A flow for about 5 minutes. This has mastered the power supply without any problems. Also, the oscilloscope showed no abnormalities on the 24V line (without load: 24.2V, with load 23.5V).
Well, the power adapter may be cheap, but it is quite suitable for use with the heater. The voltage on the running heater showed on the Oszi spikes of 2.3V with a frequency of about 500 kHz (probably from the fan). A 1000μF capacitor in parallel with the heater completely eliminated the spikes. However, these spikes can not affect the galvos or their voltage signal!
The grounding concept of the Moai is not ideal. The frame and the steel plates, the galvos, their cable shield and the driver heatsinks are more or less at the same potential, namely GND. That should be enough to derive strong electromagnetic interference from outside. Better would be a complete shielding of the electronic modules (CPU, power supply and galvo driver), but not necessarily.
The problem of waves (layer shifts) in print is guaranteed not to be caused by external electromagnetic interference.
The separate power supply of Moai and heater is also fine. And it is also an elegant solution to use only low voltage in the device. This is safer and reduces the protection costs considerably .
One/the problem is the temperature fluctuations inside the printer !!!
In my view, the temperature should be kept as constant as possible (fluctuations <0.5 ° C).
Sure, there are also other causes for a distorted print image. These include the “shaky” construction of the Z-axis on the Moai 130 and the large peeling forces.
There is a clear feature when the temperature is the source of the disturbance:
The distance between the waves depends on the printing time of the layers.
If the Z-axis does not turn “round”, then the distances between the disturbances are constant, no matter if much or little was lasered on the planes.