Quote Originally Posted by RyanLD View Post
Kvant technical support informed me that this is the overdrive protection for the scanners
Which is what I suspected. Many scanner amps use a resetable poly-switch to accomplish this. But yeah, overdrive = overcurrent, which trips the polyswitch (or some other safety circuit) and that shuts down the amp before the scanners overheat. Nice to confirm that. Usually the solution is to scan at a narrower angle or use a less complicated pattern.

But it's *NOT* normal to trigger these sorts of overdrive protection circuits with normal scanning. I think something is wrong here. Either the circuit is tripping too soon or you have a scanner that is drawing too much current (bad bearing, shorted winding, etc).

if the beam enters unsafe areas the emergency stop should be used to terminate the output.
Well of course. Odd that they felt the need to state this. Everyone knows what the E-stop is for. But the E-stop extinguishes the laser output. This scanner overdrive protection does not extinguish the laser operation. I don't see why they felt this was relevant to your problem at all. It almost looks like they are trying to say that "it's not our problem".

The key point here is that you should not be tripping the scanner overdrive protection circuit during normal scanning in the first place. Sure, if you're trying to scan the ILDA test pattern at 65 degrees, you're going to trip it. But running a stock beam show? No way. Something is wrong.

There is no safety system that compares the expected angle of the scanner to the actual angle.
Right. That would be a scan-fail system (like PASS) and would add a great deal to the cost of the projector. None of that changes the fact that for normal scanning you shouldn't be tripping the protection circuit.


EDIT - PS: Thanks to Ryan from Pangolin for confirming that the new shutter is not a VRAD and is in fact just a simple motor with a spring-return. Although it does seem odd that Justin would claim that this motor has the same response speed as a VRAD actuator. I find that very hard to believe, although it could be that Justin simply didn't know about the change to the cheaper motor for the new shutters...