Help please. My K40 has failed half way through a big job (Whisperer estimated 9hr 13m - raster engraving at 100mm per sec and current set at 20% drawing about 2 ma).
The laser has stopped firing, all I’m getting now on test fire is a sparking at the rear of the CO2 tube, but nothing through the tube and it’s not drawing any current. I’m guessing that I need to buy a new tube.
But my worry is that the failure was caused by something other than the tube itself and if I fit a new one will it fail again.
like @Ariel_Yahni_UniKpty say it’s look like arcing.
this mean the current found a shorter way to go. check insulation on the tube connection (remember the silicone tube you got with your K40).
Its hard to see the arc. Is it inside the tube or arching to the case anywhere?
Looks more like inside the tube?
This could be either a tube or a power supply, its hard to know which.
Can you see any arching inside the power supply.
Logically:
– I do not see the tube ionizing.
– Since this was a sudden failure my bet would be the LPS. Further I would suspect the HV transformer.
You can try testing it this way: WARNING: the LPS outputs lethal voltage. At all times stay away from the laser tube while power is applied
YOU DO THE FOLLOWING TEST AT YOUR OWN RISK
With power off:
You can connect one end of a wire to ground and tape the other end to the tube about 1" away from the anode.
With power on and your positioned away from the tube:
Turn on the machines power and briefly push the test button to fire the laser. Caution: Do not hold down on the button. Arching to ground for long periods can damage the LPS.
Results
If you get a violent arch from the anode to the ground wire then your problem is likely your tube.
If you don’t get a strong arc or any arc at all your LPS is bad.
You can buy a new LPS or replace the HVT in your current unit.
@Duncan_Caine removing the insulation (or pull it back) would be better. Before you touch or get near the anode; with the power off ground it with a chicken stick.
Connected an earth wire to my domestic wiring earth circuit
Stripped off the silicone anode insulation so that the tip of the anode is visible.
Taped the earth wire to the tube so that the exposed end was close to the tube anode, approx 15mm
Connected the power
Pressed the test switch
The arcing inside the tube continued as before but there was no arcing between the anode and the ‘taped on’ earth wire.
So I guess my power supply needs replacing, and that poses another problem, which one.
I have googled these 2 which have the same connections as mine and with the same composite plug arrangement, one is a GC model and the other is a GS model and I can’t see any difference, can you?
Good price, not much more expensive than repair! No I do not see any difference? You could email the vendor to be safe.
I assume you live across the pond?