Gina

Thank you very much. The ASI178MC is ideal for this purpose though I did get some odd colours with it - no idea why. I might go back to it but presently I'm using the mono version for higher sensitivity and resolution (or even higher sensitivity win 2x2 binning).

Any further information on this? I'm very interested to know what happened.

I used timber bracing - corner to corner inside. Didn't know about galvanised bracing tape.

Rain is on the way... Looking good though

Great start - well done

I have an eye test every year as my mother suffered from glaucoma.

In PETG that should be strong enough for anything you can lift! Assuming a reasonable infill, of course. Very nice job.

Well done - seems you've cracked it!

At the point of the problem starting the image goes from normal to a blue/purple sort of colour and loss of the RH columns with the columns repeated from left to right. The general image changes with changing light but corrupted. The rainwater droplets still appear and move on the LHS of the image. Is the camera working since? Or is it some sort of permanent sensor damage?

That sounds like me 🤣 I bought a batch of very small drill bits a few days ago and can I find them now I want them?? No way!! 😡

Surely the SSR will switch at the next zero crossing point after the change of DC input. Or aren't these SSRs that clever? I think this may have been updated since I read it several years ago - I don't remember reading about the PID being at 10Hz. I feel sure the instructions back then were to use bang bang mode but I could be wrong.

Several constellations showing. Pretty good that. Must try dark subtraction on mine when I get it working again.

Yes, I use the heater from Dewcontrol.com. And I cool the camera with a Peltier TEC.

Can't find exact information with Google (other search engines... ) but you want BANG BANG control rather than PID (which uses PWM). PID is good for the hotend as it holds a steady temperature but SSRs don't like it, HTH.

@Chriske I suggest you set the bed temperature control to bang-bang ON-OFF mode rather than variable (PWM). I forget what it's called in Marlin.

Looks like I may have a fake but I'm only running at 3A and the unit doesn't get warm so seems alright.

I'll be interested in reading how well it works.

Must check mine. I think the case is connected to mains earth but not totally sure. Printing ATM but I'll check continuity from SSR case to mains earth when finished.

SSRs depend on the sinewave mains current and switch at the zero crossing point thereby reducing RFI. So with 50Hz mains they only switch every 10ms. If you switch the DC control on/off frequently I can't say what will happen.

I don't use PWM for my bed - just simple ON/OFF. It cycles with ON and OFF periods of about a second or so. You can't run SSRs off PWM, they don't work that way.

That is well burnt out!!! 😮

Not a bad idea! A Nano could certainly do that but you still need some sort of mains relay. EDIT... Cross posted with Julian. He has a good point and that brings me back to the thermal fuse idea. The Duet control boards have a fault sensing routine that checks that the heating is turning on and off and I can't see the power MOSFET control failing into the ON state though I suppose it's possible.

I guess even the higher quality SSRs could fail in the same way so maybe a thermal fuse would be safer. Though a lot less convenient!

The RS-online ones are affordable, compared with the cost of everything else in a high end printer.

Yikes!!! I use exactly the same make and model! This is frightening. Seems we need some sort of safety device to cut power if the bed gets too hot. Obviously all the error catching in the world won't stop this as things are because this is the only bed heater control. I guess it needs some sort of thermal fuse attached to the bed that will break the circuit if the bed gets above say 150°C. A bimetal strip and microswitch might be possible but we don't want it resetting when the bed cools down again.