I'm going to buy a heated bed from aliexpress and was wondering the exact

I’m going to buy a heated bed from aliexpress and was wondering the exact specs this I what I’m thinking
700 watts
Ac or DC not sure?
And I’ll also need an SSR to match. Any ideas?

cant you get aluminum plate and cartridge heaters for heat bed??
if you go for that you can even get larger sizes.

With the silicone heated bed I can go as large as I need and it will have better heat spreading than having several hot spots with heat gradients around them

thats true

Go 120v, and 700w is likely overkill for 330x330. I would say 500w would be the sweet spot for that size. I went 800w for 380x380 but had to tune down max output in marlin to avoid overshoot on pid tuning. I found an equivalent of 700w would have been perfect for the 380x380 size.

Just my 2cents.

Going for 24v is a reasonable compromise as the lower current required should allow you to use standard reprap electronics without an ssr or risk electrocution by wiring a moving part up with mains power.:).

@Tim_Rastall so for a regular ingentis 330mm² is the proper size right?

I used 300mm if I recall but 330 should be fine. The principal constraint is the distance between the Z shafts which is 370 I think.

I ordered a custom one 340x340mm 550W. Powerred directly by 230V main power.

@Florian_Schutte ​ so is that AC or DC

AC Main power regulatrd by ssr

@Florian_Schutte how is your heater performing? How fast does it heat up? I Followed this an other posts about sizing the silicone heater and it turns out that 0.47 to 0.5W per cm^2 should be the right size.
I plan to heat a 310x310mm, 6mm thick aluminium bed with a 290x290mm silicone heater @230V. I’ll go for 450W.

Sounds good. I am still using my old 24v 400w one and heatup on a 3mm plate is fast. AC with 450 watts would be plenty.