Thanks for the reply. Yes I worked out about 280.5w
Steppers (rated current x rated voltage + 50%) = 2 x 2.8 + 2.8 = 8.4 x 5 steppers = 42w
Duet = 5w
Heater cartridge = 40w x 2 cartridges = 80w
Fans = 3w x 2 fans = 6w
Panel Due = 3.5w
Heated Bed (4 ohm of resistance according to my multi-meter at least) = 144w
I thought less complication might be a good thing!
Yes I am beginning to wonder. Sadly a new Duet set up without a PSU is not much good to anyone. How would this sound to you as a suitable replacement?
Ok, this gets stranger.
Attaching a 24v fan between +V and -V,
External 5v supply connected to PV (+5v red wire) and -V (GND white wire).
Turning on 5v power and then PSU and both the 24v fan and the PSU fan rotate as expected but only for a few seconds. Turning off both the 5v and the PSU then turning on only the PSU and again both the 24v fan and internal fan rotate but this time for about 10 seconds and then stop!
I'm not entirely sure why or what this means…...............
Thanks very much for both of your replies.
I see what you are saying and it does make sense to me but I'm a little concerned about trying anything that may mean I can't return it if that's what it comes to. Just to confirm though that although there are 2xV+ and 2xV- there is only 1xRC and 1xPV if that makes things any clearer?
Perhaps I have simply bought the wrong thing? Any suggestions for viable alternatives would be appreciated.
I have my Duet already to go but I haven't yet connected it. I wanted to check that the PSU was working correctly before joining it up. I have been checking the voltage using each combination of the V+ and V- terminals and that is where I get the 0.8v reading. The other two terminals are marked RC and PV which I am a little unsure about.
So I have myself a problem which I am hoping someone can resolve for me - possibly by saying no you are just an idiot…...
I bought myself a Meanwell SPV-300-24 power supply which arrived yesterday. I wired it up with an old PC power cable which I have since confirmed is fine by connecting it up to a 12v power supply I had lying idol. The cable itself is definitely wired in correctly (L,N,E) and I have confirmed that a connection has been made in each case with a multi-meter (not while plugged in, obviously). This is the first power supply I have owned that doesn't have a switch to select either 120v or 240v. I am in the UK so use 240v (I realise officially 230v) but the unit is designed to automatically deal with either or so I believe.
The problem is when I turn the Meanwell on not a lot happens. No noise, no fan activity, there isn't a power on LED unfortunately which in this case would help. However, when plugged in I do record a small voltage of 0.8v from the V+ V- terminals.
Essentially what I am looking to find out is whether I have bought a dud or I'm missing something and I'm the dud!
Any help on this matter would be most gratefully received.
Thank you muchly for the swift replies. That is essentially what I had assumed but nice to find out for sure.
I am just about to order the seemingly wonderful smart effector but look as I might I can't seem to find the answer to one particular question. So, at the risk of asking something obvious and in so doing looking a bit stupid, is the optional e3d V6 for 1.75mm or 3mm filament? There, I've said it…......
I'm wondering if buying a different heated bed with a higher resistance would be the better way to go:
With 4 ohm of resistance that equates to 144w and so a total of around 280w with a happy amount of wiggle room lending itself nicely to a MeanWell 300w PSU. Possibly I have just answered my own question….......
I'm happy to say that I received a reply from Sinton today saying 'if you use 24v , the resistance should be around 2.8~3 ohm.' So, using
Current = Voltage / Resistance
Power = Voltage * Current
Gives me between 192v and 206v which was a bit more than I was expecting. Coupled with my previous workings out that means I'm going to need 136.5w + 206v = 342.5v with a bit of wiggle room so lets say 350v. Shame really as I had just about settled in my mind on a MeanWell 300w PSU.
Steve
Thank you both dc42 and Jeff ((In)Sanity) for your quickly given and helpful advice.
I'm pleased to know that I was at least on the right lines. I have sent a message off to Sintron so I'll see if I get a reply and take it from there. No reply and I'm happy to take dc42's estimate of 100w-130w as a base and then I guess it's a question of how much damage I can justify doing to my already battered wallet. Cheap, big and bulky and undoubtedly less efficient or not quite as big and bulky, well made and reliable but 4 times the price:
Life in a nutshell really.
Steve
I've had my delta printer up and running for about 18 months and have decided that the time has come to upgrade from my Ramps 1.4 with 1.8deg steppers and 12v electrics to a Duet Wifi with 0.9deg steppers all running on 24v. I initially want to set up my printer with just one extruder before adding a second in the very near future.
I have settled on using these stepper motors:
http://uk.stepperonline.com/09deg-nema-17-bipolar-stepper-motor-2a-46ncm-17hm192004s-p-122.html
which I intend to use for my three directional motors as well as the extruder(s). Hoping that I have made the correct choice regarding these motors I then moved on to considering a suitable power supply and this is where I'm struggling.
Refering to both:
http://reprap.org/wiki/Choosing_a_Power_Supply_for_your_RepRap
https://duet3d.com/wiki/Choosing_the_power_supply
Using the formula Power (Watts) = Voltage (V) x Current (A 
Steppers (rated current x rated voltage + 50%) = 2 x 2.8 + 2.8 = 8.4 x 5 steppers = 42w
Duet = 5w
Heater cartridge = 40w x 2 cartridges = 80w
Fans = 3w x 2 fans = 6w
Panel Due = 3.5w
Radial fans = ?
Which totals 136.5w
What I can't work out or find is the wattage needed for my heated bed:
http://www.ebay.co.uk/itm/161744356159?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I read that "The Duet WiFi is able to supply 15A to a heated bed" (https://duet3d.com/wiki/Power_wiring) meaning a maximum of 24v x 15a = 360w.
Should I therefore be thinking of 136.5w + 360w = 496.5w and so buy an LED PSU that can provide 600w at 25A? I'm thinking this is a huge wattage and I may infact have got the wrong end of atleast one stick. Any input or pointing out of the obvious would be gratefully received.
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