I need help with upgrading to a large heat bed!!!

[SmoothOl]

hellooo everyone

im looking to use a MKS board with solid state relay for a 350x350mm 12v 440w heatbed.. the other parts add up to 330w so there will be a 33% overhead with a 12v 1000w atx PSU.

will this circuit and power supply work okay??


heres the set up for the SSR:

[EagleSeven]

??? Won't the PowerSupply and Motherboard in your printer handle the power needed for new heated bed ?

If not, then adding another supply and a relay is a Good way to connect it up.
Or you could use the new high-wattage Supply to power Everything,
if the Mobo will handle the added current to bed.
So if your printer has a heated bed Now, it should handle the larger size bed Also,
No need for a relay.

But the Main problem is 'how are you going to Control the Temp of bed',
if the Mobo and firmware on it are not designed to handle a heated bed ??
The bed heater needs to turn off&on many times during a print to control Temp.
Mobo also needs a connector for thermocouple-wire going to bed, to monitor temp.

[SmoothOl]

??? Won't the PowerSupply and Motherboard in your printer handle the power needed for new heated bed ?

If not, then adding another supply and a relay is a Good way to connect it up.
Or you could use the new high-wattage Supply to power Everything,
if the Mobo will handle the added current to bed.
So if your printer has a heated bed Now, it should handle the larger size bed Also,
No need for a relay.

But the Main problem is 'how are you going to Control the Temp of bed',
if the Mobo and firmware on it are not designed to handle a heated bed ??
The bed heater needs to turn off&on many times during a print to control Temp.
Mobo also needs a connector for thermocouple-wire going to bed, to monitor temp.

im making a prusa i3 using a MKS board:
http://www.ebay.co.uk/itm/MKS-Base-V...EAAOSwKIpWBPvC


im not entirely sure if there would be a problem with hooking up the heatbed, psu and circuit board as usual. However most of the threads i've been looking at on upgraded heatbeds have said to use a relay so that the board doesnt burn out.

im split between a few options:

1. set up as usual, psu connected to mks board connected to heatbed, which is more then likely to burn out.

2. go with the 12v 1000w atx psu and solid state relay with hope for the best (no burnt parts)

3. have two seperate psu: one 12v 400w atx to power the board and motors etc. , one to power the 440w heatbed (and control it through a PID temperature control thermostat.




what do you reckon???


also do you have any suggestions of how i would be able to find out how much power/current the mks board can take before tssss boom

[EagleSeven]

I noticed that the MKS board, on eBay, Has a Bed-Heater connector,
so it seems that output should handle the heater in bed you have pictured.

(But the board in your picture is a different design, that does not look as good)

You should add a Fan to cool the MKS, and could add small heat-sinks to those chips on board.
(80 or 90mm would be good size Fan for that)

You should try to use only One PowerSupply !

[SmoothOl]

I noticed that the MKS board, on eBay, Has a Bed-Heater connector,
so it seems that output should handle the heater in bed you have pictured.

(But the board in your picture is a different design, that does not look as good)

You should add a Fan to cool the MKS, and could add small heat-sinks to those chips on board.
(80 or 90mm would be good size Fan for that)

You should try to use only One PowerSupply !

i've had a change of heart!!!!

im getting a 110v 1000w heatbed and connecting it to the mains. i will also use a SSR and will use the set up like shown above

im wondering what amp relay i should use? or how to calculate this? any ideas

[EagleSeven]

i've had a change of heart!!!!

im getting a 110v 1000w heatbed and connecting it to the mains. i will also use a SSR and will use the set up like shown above

im wondering what amp relay i should use? or how to calculate this? any ideas

The MKS Mobo should handle the heated-bed, if you use a fan to cool it !
(It is Designed to Do that )
If not, I would get a Different Mobo, instead of a relay !

(the Relay should Not be needed ! )
Relay is only needed when Mobo does not have a circuit to control heated bed.

[SmoothOl]

The MKS Mobo should handle the heated-bed, if you use a fan to cool it !
(It is Designed to Do that )
If not, I would get a Different Mobo, instead of a relay !

(the Relay should Not be needed ! )
Relay is only needed when Mobo does not have a circuit to control heated bed.

the motherboard is 12-24v so i doubt connecting it straight to the mains would work... it's jus fry the board?
i've ordered in a 25a ssr

im just wondering how to wire protective earth? would it connect to the relay, heatbed or???

[EagleSeven]

the motherboard is 12-24v so i doubt connecting it straight to the mains would work... it's jus fry the board?
i've ordered in a 25a ssr

im just wondering how to wire protective earth? would it connect to the relay, heatbed or???

????????????????????????????