Mains bed pwm frequency/flickering lights.

tenaja

Don't forget ohms law...a couple guys have alluded to it, but you need to embrace it.

jens55

@fcwilt said in Mains bed pwm frequency/flickering lights.:

You've got a house wiring problem.

I see two solutions short of trying to get by with a DC powered bed heater.

run another line from the load center to a dedicated outlet for your printer

get a suitably rated dual-conversion UPS to power your printer

Frederick

Those are the two choices that make sense. Note the "dual-conversion" bit. A regular UPS is not likely to fix anything and if in fact it reacts to the brown outs, it will likely kill the UPS in no time flat (of course depending on the quality of the UPS)

Surgikill

@tenaja Ohm's law is what is killing me. That, and the idiots that wired this house.

jens55

While this may sound stupid, if you want to go cheap and cheerful, get a 12 ga extension cord (HD outdoor type used by contractors) and run it from the FIRST outlet on that circuit directly to the printer.
Might want to try the printer directly on that FIRST outlet to see if it makes sense buying a long extension cord.
That way you will bypass all the joints that are made with wiring nuts for each and every outlet that is wired in a long string.

Surgikill

@jens55 I can try that, but it's going to be going all the way down my hallway. I already have one extension cord in the hallway, and it's to feed my server from a different circuit. It's not too bad if I keep the overhead lights off.

tekkydave

What type of SSR are you using. Check if it is a "zero crossing" type which only turns on/off at the mains zero-crossing points. May make a difference?

Also a lot of the cheap ones are fakes and are lower rated devices in a fake enclosure. Could be worth trying a different device from a reputable supplier.

zapta

@tekkydave said in Mains bed pwm frequency/flickering lights.:

Check if it is a "zero crossing" type which only turns on/off at the mains zero-crossing points

What is a good way to check this? Will an AM radio pick more static?

tekkydave

@zapta is there a part number on the ssr?

zapta

@tekkydave, I don't know the SSR model, I was asking regarding your suggestion to @Surgikill. Is there a simple way to test if a SSR is zero crossng?

tekkydave

@zapta I don't think so apart from the manufacturer's spec.

Surgikill

@tekkydave This is the SSR I bought.

https://www.ebay.com/itm/25A-40A-SSR-25DA-SSR-40DA-250V-Solid-State-Relay-Module-Alloy-Heat-Sink/401478280169

Probably a fake. I paid 9 bucks for it back in 2019.

Phaedrux

Why buy a fake for 9 bucks when you can get a real one (25A) with certification for 9 bucks?

https://www.auberins.com/index.php?main_page=product_info&cPath=2_30&products_id=9

or the 40A for 17$

https://www.auberins.com/index.php?main_page=product_info&cPath=2_30&products_id=30

I have this one by the way.

Surgikill

@Phaedrux Probably because this is the first time I've heard of fakes, and every time I looked up genuine ones they were 35 bucks.

Phaedrux

It was really bad a few years ago.

https://www.instructables.com/The-inner-workings-of-Counterfeit-FOTEK-SSRs/

Surgikill

@Phaedrux Great. I have like 4 of these SSR's in various projects, some using 220V and high current. Can't wait to see if any of them explode.

tekkydave

I discovered I had a fake Fotek SSR on my 750W 220V heatpad. It looks genuine but I only paid a few quid for it on ebay. To be fair it was doing its job but I didn't want to take the risk.

2017-08-30 17.00.40.jpg
I replaced it with this one from a reputable supplier (RS in the UK).

2020-03-17 11.27.04.jpg

tekkydave

If you check out https://protosupplies.com/inferior-counterfeit-fotek-ssr-25-solid-state-relays-on-the-market/ it has two pics to highlight how to spot the fake Foteks.

The Real Ones look like this:

and the fakes:

Surgikill

@tekkydave Yep, mine is fake as shit. Looks like I need to get some better ones.