Silicone bed 12V directly to PSU???

I bought silicone heatbed 12V 220W and I am wondering can I connect it directly to my 12V 30A 360W PSU not on ramps but directly to PSU and then termistor to ramps 1.4 ?

THX

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Proud owner of CTC and my newly made from scratch Prusa i3

Beer, 3D Print, Sleep and again...

If you do that how will the temperature be controlled? The thermistor only measures temperature, it doesn't control it. You'll watch as the bed temperature goes up and up until it reaches whatever it's equilibrium is, possibly high enough to burn the heater and your printer and your house to the ground.

If you don't want to connect to RAMPS, get something likes this: [www.ebay.com] and an SSR.

Edited 1 time(s). Last edit at 01/20/2016 07:32AM by the_digital_dentist.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Hehe

Ok I really dont want ssr, wires on HB gets hot like hell is fan enough to cool it down 12V 60cm?

I'm sorry, but you're not making any sense. The reason you need to heat the bed is to get prints to stick to it. If it gets too hot the prints will melt (or if it gets much too hot, it will burn your house down). If it's too cool, prints won't stick. So you must regulate the temperature. You regulate the temperature by turning the heater on and off either under PID control (for tight regulation) or bang-bang control (for less tight regulation). You switch the power on and off using an SSR or one of the MOSFETs on the controller board.

I suppose you could use a fan to blow air across the heater to regulate the temperature but I don't think you'll be able to control it very well.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I know what You are saying but You dont understand me, I know how print works and how to stick it to bed and I printed many things without heated bed, I have printer for a year now, but this build is my first time building a 3d printer and I ordered silicone pad connect it to ramps 1.4 but wires get to much heat so I unplluged and after minor issues with stepper drivers I put 60mm fan to cool my ramps board so the question is Are that enough to cool silicone pad wires connected to ramps or should I buy SSR?

Why don't you try it and see?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I want to take the load out of the ramps also(silicon heater in the future), just in case, so might try one of those units linked to.
Found a 240v one here [www.ebay.co.uk]
but also found these types
25A
[www.ebay.co.uk]
and 40A [www.ebay.co.uk]
look very small, I assume there's no need to hook up to ramps, but have to program printer to start job without heating bed.
Probe might need changing.

All of the controllers you linked to are 120-240v AC. You could use these tl externally control a heated bed if you wanted to but only on AC voltage.

To be able to switch 18.3A@12v of current you would need a DC ssr with a rather large heatsink. You could hook the heated bed output to the input of the ssr and the heater to the output powered directly by the powersupply. Plug in your thermistor and you still have a gcode compatible heated bed, and don't have to worry about forgetting the heater off.

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Prusa i3 Rework - Ramps 1.4 - E3d Lite6 - Full Graphic LCD Controller

I use the control wiring to activate the ssr and it works awesome.

cheers gmckee, I was getting a little muxdip, with 220w & 240v and 24v when what I was exploring would have been a 240v plug in heater solution, but maybe I'll just get another 24v power supply for the bed, the ssr(auber) in the other thread if I can get my hands on one, and hopefully the tips in the other thread to help me get my head around things, electronics phase me a little, as I'm a bit late to the subject, due to a cockup at school where I lost some of my chosen subjects...I lost physics electronics, never really touched the subject since, even though grandpa was an electrician, I never learned anything from him, but after he died I inherited some tools and components, which where ever I could where used in the construction of the printer, I have a big black siren & large black retro ammeter I still need to incorporate, pity he couldn't have seen the final thing, or helped build it, but life's not always fair like that.

Does anyone use ssr on the extruder heaters?
maybe i'll put the cartridge on the second psu too.
might be overkill using 2 psu's but I just want to limit the juice in the arduino

Edited 1 time(s). Last edit at 01/24/2016 03:12AM by MechaBits.

Guys thx for all help but if You want silicone heated bed and You have some prusa i3 variant You can do like me I use 12V 360W 30A power supply for LED lights bought for 30$ sillicone heater 12V 280W that I hooked up to automotive relay g.cartier 12V 50A and I dont have extra power supply just hooked it up to that power supply for my prusa and thats it in a minute my bed gets hot to 50C.

If someone need help with wiring let me know.

Hi I have a question for the digital doctor I purchased the unit you recommended for the gentleman to purchase off of ebay what would the wiring look like for setting it up for a separate power supply running to my heatbed. Thank You ! This is the unit AC 10A 110V Digital PID Temperature Controller Thermocouple Sensor LCD Display I also purchased a SSR Sunkee Solid State Relay SSR-25 DD DC-DC 25A 3-32VDC/5-60V DC SSR-25DD

Edited 3 time(s). Last edit at 02/02/2016 02:15PM by gatonini.

Hi
If you look at that unit on ebay it is 110volt is that ok to use with the heatbed ?

jumping into this conversation....

DO we modify the firmware when using a SSR?

The reason I ask, is that I I just FRIED mine at first usage after 20 mins of usage.

Luckily, My house was not burn down....

It is just the SSR that was kaput!

Mine is SSR-DD 25A
and my bed is MKA 1.3 ohms with SWPS at 13.5V
MArlin V1
Melzi V3b by Zonestar.

the temp reached so high (i left unattended) that melt the insulation I installed under the bed and also the Acrylic base that holds the heated bed got so hot that has deformed beyond
possibility to reuse it (although I will try to put it into the oven to see if I could "soften it and put it back flat"

unless I connected it in reverse (output + -) then it would make same sense, but otherwise, I suspect that we should change the settings for the temperature control...

Any feedback?

Thanks a lot

All I did on my SSR setup was to connect the wires that went from the mainboard to the heatbed originally to the control side of the SSR. Nothing else was changed. My first SSR was faulty and let the heatbed run away. Once I replaced it, it worked perfectly.

Cheap DC-DC SSRS such as SSR-25DD and SSR-40DD are NO GOOD for driving heated beds because of their high voltage drop. This has been repeated many times on these forums. Try the Power Expander from reprap.me instead. The Crydom dc-dc SSRs are also good but expensive. There is another brand of SSR that is ok and doesn't cost too much, but I don't have the link available.

Can't your electronics drive that bed heater directly?

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Me to and I did that with automotive relay, one print was 5 hours and only thing that melted cause am an idiot is electrical tape around connection that connects heatbed to relay...

As previous post DONT use cheap relays, and if You have copper mk heatbed You really dont need relay...

Edited 1 time(s). Last edit at 02/09/2016 01:28AM by Beer4Brew.

$17.00 and works perfectly with heat sink and 40mm fan.
[www.mpja.com]

x

Edited 1 time(s). Last edit at 02/17/2016 02:25PM by smoothol.

Quote
Beer4Brew
Guys thx for all help but if You want silicone heated bed and You have some prusa i3 variant You can do like me I use 12V 360W 30A power supply for LED lights bought for 30$ sillicone heater 12V 280W that I hooked up to automotive relay g.cartier 12V 50A and I dont have extra power supply just hooked it up to that power supply for my prusa and thats it in a minute my bed gets hot to 50C.

If someone need help with wiring let me know.

hi mate, i'm a little bit of a novice when it comes to electronics, im looking to do a similar set up as you and was wondering if you could share a bit of knowledge with me!


im looking to make a prusa i3 with a 350x350mm heatbed that runs at 330w. I will use 850w atx PSU and MKS v1.3 board.

how do i set up a SSR to limit the power to the controller? and would it need to be DC-DC or AC-DC ?
also


if the all the components, excluding the heatbed, need 340w then what amp SSR do i need?


any advise would be appreciated! smiling smiley

For a heated bed of that size, you should use one of the following:

1. AC mains voltage bed heater, driven using a DC-AC SST. Only do this if you are knowledgeable about and comfortable with doing mains voltage wiring.

2. A 24V bed heater (in which case you may as well run the entire printer on 24V, assuming you use 24V-capable electronics). The bed heater will draw 13.75A. Some electronics can handle this current directly (e.g. the Duet 0.8.5 should be OK at this current). Otherwise, use a good (low drop) DC-DC SSR or the Power Expander from reprap.me

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

330W but what is voltage? 12V or 24V, 330W/12V=27.5A or as dc42 say 330W/24V=13.75A
So You buy SSR acording to that equation.
Didnt work with other relays so I cant give You advice which one to buy, I hooked up Automotive relay 12V 50A that is low cost works like a charm (printing 12 hours a day for a month now with no problems) but if You need help with wiring, any relay that You choose I can help, or You just need to read schematic of relay its not that difficult, will make instructables of my ups and downs in next couple of days after returning from IMOT, will eat, drink beer and try to sell prints while am there

Quote
dc42
For a heated bed of that size, you should use one of the following:

1. AC mains voltage bed heater, driven using a DC-AC SST. Only do this if you are knowledgeable about and comfortable with doing mains voltage wiring.

2. A 24V bed heater (in which case you may as well run the entire printer on 24V, assuming you use 24V-capable electronics). The bed heater will draw 13.75A. Some electronics can handle this current directly (e.g. the Duet 0.8.5 should be OK at this current). Otherwise, use a good (low drop) DC-DC SSR or the Power Expander from reprap.me

could I not use 12v heatbed and a SSR with a higher amp resistance for instance 50A RRS?

Quote
Beer4Brew
330W but what is voltage? 12V or 24V, 330W/12V=27.5A or as dc42 say 330W/24V=13.75A
So You buy SSR acording to that equation.
Didnt work with other relays so I cant give You advice which one to buy, I hooked up Automotive relay 12V 50A that is low cost works like a charm (printing 12 hours a day for a month now with no problems) but if You need help with wiring, any relay that You choose I can help, or You just need to read schematic of relay its not that difficult, will make instructables of my ups and downs in next couple of days after returning from IMOT, will eat, drink beer and try to sell prints while am there

thanks, could you please post link for wirings when you have

Quote
smoothol

Quote
dc42
For a heated bed of that size, you should use one of the following:

1. AC mains voltage bed heater, driven using a DC-AC SST. Only do this if you are knowledgeable about and comfortable with doing mains voltage wiring.

2. A 24V bed heater (in which case you may as well run the entire printer on 24V, assuming you use 24V-capable electronics). The bed heater will draw 13.75A. Some electronics can handle this current directly (e.g. the Duet 0.8.5 should be OK at this current). Otherwise, use a good (low drop) DC-DC SSR or the Power Expander from reprap.me

could I not use 12v heatbed and a SSR with a higher amp resistance for instance 50A RRS?

Bad idea. Dealing with such high currents is not nice, and keeping the resistance low enough is not easy.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42

Quote
smoothol

Quote
dc42
For a heated bed of that size, you should use one of the following:

1. AC mains voltage bed heater, driven using a DC-AC SST. Only do this if you are knowledgeable about and comfortable with doing mains voltage wiring.

2. A 24V bed heater (in which case you may as well run the entire printer on 24V, assuming you use 24V-capable electronics). The bed heater will draw 13.75A. Some electronics can handle this current directly (e.g. the Duet 0.8.5 should be OK at this current). Otherwise, use a good (low drop) DC-DC SSR or the Power Expander from reprap.me

could I not use 12v heatbed and a SSR with a higher amp resistance for instance 50A RRS?

Bad idea. Dealing with such high currents is not nice, and keeping the resistance low enough is not easy.

ahhh okay i may switch to 24v then.... so to sum it all up theres no way of controlling the temperature of the heatbed from the MKS board??

You can, people do that, but I would avoid it, its better with relay...

And why You dont want to use 12V heat pad?

Edited 1 time(s). Last edit at 02/18/2016 03:31PM by Beer4Brew.

Quote
Beer4Brew
330W but what is voltage? 12V or 24V, 330W/12V=27.5A or as dc42 say 330W/24V=13.75A
So You buy SSR acording to that equation.
Didnt work with other relays so I cant give You advice which one to buy, I hooked up Automotive relay 12V 50A that is low cost works like a charm (printing 12 hours a day for a month now with no problems) but if You need help with wiring, any relay that You choose I can help, or You just need to read schematic of relay its not that difficult, will make instructables of my ups and downs in next couple of days after returning from IMOT, will eat, drink beer and try to sell prints while am there

are you able to control the temperature of the heatbed through the control board by using the automotive relay? or do you use a manual set temperature device?

Yes I control it with my board

12v means high current which = fatality


lol


so should i do the same set up as you with an automotive relay?
please could you share the component and wiring details