I have changed from the original heated bed (because of uneven bed level issues) and the original heated bed draws around 2,4A. The new heated bed which is a MK3 with integrated 3 mm aluminium plate, and it draws around 7,1A.
In this situation I would like to know how much current is the Velleman K8200 controllerboard (94V-0) able to handle? Can it handle the new heated bed or do I have to make some kind of external powersupply with a relay or something controlled from the controllerboard’s output? I have confirmed that the original powersupply is not able to handle the new heated bed since the overall amps drawn by the printer while working, is above the max of 6,67A the powersupply is rated, but I found a new 16,5A switchmode powersupply that can handle the amps, but now I am concerned about the controllerboard.
The best way is to use a switch and use a seperate power supply.
I myself use something like this reprap.me/power-expander.html for my heatbed (on 24V)
Iam running my original bed at aprox 24V AC via a Solid State Relay SSR-25DA. Bedwires directly to the input of the SSR. The outputside is connected to a separat
24V AC transformer. Have worked for 4 years now.
tholsen: 7.1A at what voltage?? The same as the velleman at 15v? Or 7.1A at 24v ? You need to know at wich voltage you are going to run it to know what amperage
it will draw.
AndersE: The new heatbed draws more amps, and when I skipped the original Vellemann powersupply and changed to a new powersupply with more amps, my idea was not to change anything and still let the mainboard handle the new heatbed, and in this case I wondered how much amps the onboard transistor could handle, not to mention the printboard itself. I wouldn’t risk ruining the mainboard due to too much amps.
In the meantime I have used a little relay for switching on/off the heatbed, and using the 12V (if supply is 12V) from the heatbed output to control the relay. The main current for the heatbed is then routed around the mainboard instead of through. And it works perfect.