Onyx Rev 2 24 V question

Check out how others are building and modding their own heated beds
User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Onyx Rev 2 24 V question

Postby mlapaglia » Fri Nov 07, 2014 12:17 am

I got a mean well 24v psu, a crydom ssr and a 12v converter to power the rambo. I've read that extra resistance is required between the ssr and the onyx bed. I wasn't sure how much I should add for the Rev 2, everything I've read is for later version boards.

User avatar
Eaglezsoar
ULTIMATE 3D JEDDI
Posts: 7185
Joined: Sun Apr 01, 2012 5:26 pm

Re: Onyx Rev 2 24 V question

Postby Eaglezsoar » Fri Nov 07, 2014 6:25 am

mlapaglia wrote:I got a mean well 24v psu, a crydom ssr and a 12v converter to power the rambo. I've read that extra resistance is required between the ssr and the onyx bed. I wasn't sure how much I should add for the Rev 2, everything I've read is for later version boards.

No extra resistance is needed.
Could you tell me where you read that?
“ Do Not Regret Growing Older. It is a Privilege Denied to Many. ”

User avatar
teoman
ULTIMATE 3D JEDDI
Posts: 1783
Joined: Sat May 24, 2014 5:43 pm

Re: Onyx Rev 2 24 V question

Postby teoman » Fri Nov 07, 2014 6:57 am

The bed is the resistance or load.
When on mobile I am brief and may be perceived as an arsl.

User avatar
Jimustanguitar
ULTIMATE 3D JEDDI
Posts: 2632
Joined: Sun Mar 31, 2013 1:35 am
Location: Notre Dame area
Contact:

Re: Onyx Rev 2 24 V question

Postby Jimustanguitar » Fri Nov 07, 2014 8:06 am

I'm running my 24v supply directly through an SSR and into the bed. That's ok to do.

Where you may change the resistance, if you're really picky, is on the drop down resistor for the LED. You can get away without doing it though, it's just the electronics elitists that would tell you that you 'have to' :)

rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Fri Nov 07, 2014 8:17 am

Does your Mean well supply have adjustable voltage? How many watt is it?

I adjusted my 500W Mean well down to 20.5V so it wouldn't go into current limiting. It worked at 24V, it just made a ton of noise as it was going into a hiccup limiting mode.

If you have a clamp-on DC ammeter you can adjust the voltage until the ammeter shows the rated current of the supply when the bed heat is first turned on. Be sure to measure the 12V converter input too with the hot end warning up and the steppers on.

User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Re: Onyx Rev 2 24 V question

Postby mlapaglia » Fri Nov 07, 2014 9:41 am

Maybe I misread it. If you apply 24v @ 20 amps to the bed will it be too much power?

I got this PSU
http://www.ebay.com/itm/161457595622

and this SSR
http://www.ebay.com/itm/400732633009

So just hook them up to the bed and let it roll?

Thanks guys :)

rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Fri Nov 07, 2014 9:52 am

Yes those are the same ones I used, maybe you got them from my build thread. I don't know the resistance of the rev 2 bed (I have rev 7) but you should probably turn the supply down to around 20V. There is a little adjuster in the corner.

User avatar
Jimustanguitar
ULTIMATE 3D JEDDI
Posts: 2632
Joined: Sun Mar 31, 2013 1:35 am
Location: Notre Dame area
Contact:

Re: Onyx Rev 2 24 V question

Postby Jimustanguitar » Fri Nov 07, 2014 10:03 am


rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Fri Nov 07, 2014 10:10 am

Jimustanguitar wrote:Here's another 40A DC SSR option.

http://www.amazon.com/gp/product/B009X1 ... UTF8&psc=1


I bought a 100A Fotek and it was much hotter than my 40A Crydom. There is no way it would truly handle 100A. I'm not sure if all Fotek are mislabeled like this.

User avatar
teoman
ULTIMATE 3D JEDDI
Posts: 1783
Joined: Sat May 24, 2014 5:43 pm

Re: Onyx Rev 2 24 V question

Postby teoman » Fri Nov 07, 2014 10:48 am

How many watts are the heated beds rated to?

You cant go too fast. If you were to heat the bed up under a second then the print would start but the heat would not have propagated yet to your build surface...
When on mobile I am brief and may be perceived as an arsl.

User avatar
Eaglezsoar
ULTIMATE 3D JEDDI
Posts: 7185
Joined: Sun Apr 01, 2012 5:26 pm

Re: Onyx Rev 2 24 V question

Postby Eaglezsoar » Fri Nov 07, 2014 11:12 am

teoman wrote:How many watts are the heated beds rated to?

You cant go too fast. If you were to heat the bed up under a second then the print would start but the heat would not have propagated yet to your build surface...


I have used 400 watts into my revision 6 bed and had no problems but I would not recommend this for other users.

The Mean Well Power supply should be set at approximately 20V output, the SSR should be on a heatsink designed for it.
“ Do Not Regret Growing Older. It is a Privilege Denied to Many. ”

User avatar
teoman
ULTIMATE 3D JEDDI
Posts: 1783
Joined: Sat May 24, 2014 5:43 pm

Re: Onyx Rev 2 24 V question

Postby teoman » Fri Nov 07, 2014 11:19 am

How fast was it at 400W.

And does an official rating exist?
When on mobile I am brief and may be perceived as an arsl.

User avatar
teoman
ULTIMATE 3D JEDDI
Posts: 1783
Joined: Sat May 24, 2014 5:43 pm

Re: Onyx Rev 2 24 V question

Postby teoman » Fri Nov 07, 2014 11:26 am

Is there also a temperature rating for it?
When on mobile I am brief and may be perceived as an arsl.

User avatar
Eaglezsoar
ULTIMATE 3D JEDDI
Posts: 7185
Joined: Sun Apr 01, 2012 5:26 pm

Re: Onyx Rev 2 24 V question

Postby Eaglezsoar » Fri Nov 07, 2014 11:32 am

teoman wrote:How fast was it at 400W.

And does an official rating exist?


I think it took a little over 10 minutes to reach 95C and as far as I know, there is no official wattage rating.

If I had to recommend what to use for a first time user, I would recommend running the bed from 12V because I
do not want a new user burning up his heat bed. We know that the bed will handle 20+ volts but to recommend this
would not be best, the chances of a burned out bed is just to great.
“ Do Not Regret Growing Older. It is a Privilege Denied to Many. ”

rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Fri Nov 07, 2014 11:34 am

My rev 7 bed draws 23.5A at 20.5V for 482W (cold). It took 190 seconds to go from 17C to 90C. This is with the standard boro glass on top, and the melamine snowflake on the bottom.

Assuming the Onyx is made from FR4 fiberglass, the glass transition temperature is about 130C. So I'd say it's good for 120C.

User avatar
Eaglezsoar
ULTIMATE 3D JEDDI
Posts: 7185
Joined: Sun Apr 01, 2012 5:26 pm

Re: Onyx Rev 2 24 V question

Postby Eaglezsoar » Fri Nov 07, 2014 12:48 pm

rpress wrote:My rev 7 bed draws 23.5A at 20.5V for 482W (cold). It took 190 seconds to go from 17C to 90C. This is with the standard boro glass on top, and the melamine snowflake on the bottom.

Assuming the Onyx is made from FR4 fiberglass, the glass transition temperature is about 130C. So I'd say it's good for 120C.


Wow, that is fast at reaching temperature. I don't have a Rev7 bed but it's resistance must be the lowest of the beds they have produced.
Good job in getting to work so well!
“ Do Not Regret Growing Older. It is a Privilege Denied to Many. ”

User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Re: Onyx Rev 2 24 V question

Postby mlapaglia » Fri Nov 07, 2014 2:26 pm

Do I adjust the power supply to 20 volts when it is or isn't under load?

User avatar
Eaglezsoar
ULTIMATE 3D JEDDI
Posts: 7185
Joined: Sun Apr 01, 2012 5:26 pm

Re: Onyx Rev 2 24 V question

Postby Eaglezsoar » Fri Nov 07, 2014 2:42 pm

mlapaglia wrote:Do I adjust the power supply to 20 volts when it is or isn't under load?

When it is under load.
“ Do Not Regret Growing Older. It is a Privilege Denied to Many. ”

User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Re: Onyx Rev 2 24 V question

Postby mlapaglia » Fri Nov 07, 2014 2:59 pm

This is where I saw the resistance message: http://seemecnc.com/products/24-volt-onyx-r3-heated-bed

It looks like it might be a special case though since the traces are larger than normal.

12 gauge wire to hook the 24 volts to the heat bed enough?

rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Fri Nov 07, 2014 4:21 pm

12 AWG will work, but it's pushing it. 10 AWG is better.

User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Re: Onyx Rev 2 24 V question

Postby mlapaglia » Sat Jan 17, 2015 10:20 pm

Alright I finally had some time to get everything set up. The damn thing heats up to 100C in 5 minutes... Wowza. I know the aluminum spreader and glass take a while to catch up, but that beats 25 minutes with 12V.

My only concern right now is with the PSU. When it kicks on the lights in my room dim. Is the PSU really putting that much of a load on my lines? When the SSR starts switching the lights flicker.. I take this to mean the lines in my house can't handle the current needed to heat the bed, similar to a space heater?

User avatar
nitewatchman
Printmaster!
Posts: 625
Joined: Thu May 01, 2014 9:51 pm
Location: Birmingham, Alabama

Re: Onyx Rev 2 24 V question

Postby nitewatchman » Sat Jan 17, 2015 10:35 pm

The p/s should only draw about 7A or so max on the mains side , mine is controlled by an IEC switch fused at 10A.

Something else would seem to be going on. As a matter of a fact, it is a little unusual for the overhead lights and outlets to be on the same circuit unless this is an older house. Electrical Codes in most areas do not approve this.

Are your lights possibly running from the same outlet or an outlet on the same circuit? What else is on the circuit that the printer is drawing from?

It is also possible that if the light is controlled by an electronic device like X-10 or modern equivalent or an electronic dimmer that noise from the p/s could be switching the device.

User avatar
mlapaglia
Printmaster!
Posts: 121
Joined: Sat May 24, 2014 10:41 am
Location: Indianapolis, IN

Re: Onyx Rev 2 24 V question

Postby mlapaglia » Sat Jan 17, 2015 10:40 pm

We don't have fancy ceiling lights here! These are just floor lamps that plug into the wall. Yes they are on the same circuit. We have another room next to the one the printer is in that flickers, but not as severely. I am not sure if that room is on the same circuit though, I can check. Is it noise that the PSU is generating that is going into the house possibly?

gschora
Plasticator
Posts: 12
Joined: Tue Sep 10, 2013 2:28 pm

Re: Onyx Rev 2 24 V question

Postby gschora » Mon Jan 19, 2015 6:54 pm

@rpress
did you also modify the bed pid max value?

The reason because I'm asking is, that I also did the conversion to 24V using a Meanwell 600Watt psu and 100A ssr, and I think i just wrecked my v2 Onyx. :-(

When I heat my bed a section in the middle with a diameter of around 10cm stays cool and won't heat.

rpress
Printmaster!
Posts: 178
Joined: Fri Oct 03, 2014 1:35 pm

Re: Onyx Rev 2 24 V question

Postby rpress » Mon Jan 19, 2015 9:34 pm

gschora wrote:@rpress
did you also modify the bed pid max value?

The reason because I'm asking is, that I also did the conversion to 24V using a Meanwell 600Watt psu and 100A ssr, and I think i just wrecked my v2 Onyx. :-(

When I heat my bed a section in the middle with a diameter of around 10cm stays cool and won't heat.


No, I didn't change the PID max. Did you turn the supply down to 20V or so?


Return to “Heated Bed How-To's”

Who is online

Users browsing this forum: No registered users and 1 guest