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DeltaCon wrote:Maybe I misunderstood, Jim, but are you running the whole mikmak just on 15A?
Then why do SeeMe and most of the forumbrothers here advice a PSU around 30A?

12v x 30A = 360 watt
24v x 15A = 360 watt

Also, the bed is the main power draw. Without the bed being on the PSU (He said he was using a 110V silicone heater), it's much less loaded. (The rambo, if you exclude the bed, draws up to 10 amps with the stock fuse's.)

Decent prices on the recommended MW SP-500-24

http://www.ebay.com/itm/MW-SP-500-24-Me ... SwaA5Wl8Bv

http://www.ebay.com/itm/MW-SP-500-24-Me ... Swv0tVeMfO

These are Ebay and will sell quickly.

How loud is the 500w 24v meanwell? I have the 750w one and god it's so noisy.

bob64 wrote:How loud is the 500w 24v meanwell? I have the 750w one and god it's so noisy.

Very loud. I cut the 24V fan connection and connected in a motor controller so that I could slow down the fan a little.

what about SE-450-24 ? It's much cheaper here in Russia.

Renha wrote:what about SE-450-24 ? It's much cheaper here in Russia.

That looks to be a good supply and on ebay it averages $80 to $90 USD.

It's about $65 here in Moscow. But i'm thinking more about power, is 450W sufficient for 24v RMAX ONYX, couple of 24v heater cartridges, and 6 steppers working at 24v?

It does not have enough power to drive the bed at 24 volts, much less anything else. If you want to use it, you will need to turn the trim pot down on the one for the bed, and potentially add a resistor in series. To drive anything else, you will need another power supply

Unless it's a current limiting supply and you can run it at full throttle without hurting anything.

Jimustanguitar wrote:Unless it's a current limiting supply and you can run it at full throttle without hurting anything.

You can control either voltage or the current, not both. When the current has to be limited, it results in a reduction of the output voltage. This often is not what you want. Might as well buy either a lower voltage or higher current supply in the first place.

ok, so how many watts should I have then?

All of them of course!

g.

At least 500. If you have a multimeter, you can determine it for the bed you have pretty easily. (24^2)/Resistance of bed will give you wattage. for 1.1, that's 523W. for 1.2, that's 480.

When using a 24v PSU to run everything and using an SSR with the bed, is a connection still required to the RAMBO on the Heated Bed pins?

If so I'm going to use a 24-12v step down when it and the damn SSR arrives (moans about the Royal Mail for an hour), should I use a 12v or a 24 connection?

The heated bed connection on the Rambo is what triggers the SSR, so yes it is still used.

Sorry I don't think I made my question very clear. I understand that the green phoenix connect sends the signal to the SSR, what I meant is the black power connector on the right of the rambo which is receives the input from the PSU. Will a connection in the top two ports for ground and 12/24v be required still?

I haven't got all the components so haven't been able to play around. I would have thought that as power is drawn direct from the PSU and through the SSR that a connection there wouldn't be needed unless the Rambo requires power through there to send signal.

Apologies if your answer above actually answers the question!

You still need power to the heat bed rail for the heat bed output to work. It won't draw much current since all it's doing is operating the SSR.

Got you. Does it matter if it 12 or 24v?

Not a whole lot. I personally would use 12V for that, and 24 for the steppers (more power is more potential), with 12V for the fans, LED, ETC.

Okay I'll wire the step down into the bed and logic/fans and 24 to the steppers.

I assume one needs to change the motor current I'm the firmware to account for the increased voltage...?

Pictures will be forthcoming, thank you all for your assistance once again

Most people seem to go for the Meanwell SP-750-24 for wpowering the whole thing inclusing the bed. But they are so expensive, and The cheap one like this:

http://www.ebay.com/itm/Meanwell-Power- ... 1336598671

does 65 USD just to get to the Netherlands...
Is there anything a bit cheaper and easier to come by in Western Europe that fits as a good alternative? Most stores around here want between 250 and 350 Euro for that Meanwell...

My only advice would be to just keep an eye out on eBay and similar sites. It took me 3 months of waiting to get the PSU at the right price 90gbp including shipping.

For the SP-750-24 rather than the newer RSP. This is just one of the aspects I think we in Europe have to bite the bullet or bide our time...

Sorry for the disappointing answer

dcfc_sandy wrote:This is just one of the aspects I think we in Europe have to bite the bullet or bide our time...

Yeah, I like the Rostock a lot, but I can imagine next time I choose it will be a Western-European based brand.

dcfc_sandy wrote:For the SP-750-24 rather than the newer RSP.

Can you explain the differences, and why the older one is better?

It's frustrating because the kit price for the printer is amazing but sourcing components in western Europe is something that brings tears to the eyes... Even the kit was £999 father than $999 but I think they have some additional sales tax after...maybe?

I think the next purchase will be something Cartesian and pretty much plug and play haha. But I do love Rusty (my loving Max name).

I am by no means 100% sure but I looked through the data sheets before purchasing and found nothing that screamed I need that one! The key differences I highlighted are the RSP has 2 fans, slightly better efficiency (1-3%) and some extra connector pins such as a 12v 0.1A pin and a load monitoring pin, I personally had nonuse for these. Some members have used the RSP and everything is fine so nothing to be concerned with, I think end of the day it comes down to price.