1 Topic by bowvmi2001 (edited by bowvmi2001 2013-04-24 13:43:27)

  • bowvmi2001
  • Member
  • Offline
  • Registered: 2012-11-18
  • Posts: 23

Topic: Hot End Burned Out? (12v vs. 27v)

I haven't printed in a few weeks and today I decided to print some items.  The machine started to heat and got up to 200 degrees and extruded fine.   Then the temp started to drop off and would not reheat.  Okay, bad heating core, I have a spare.  Switched over to my spare hot end and started over.  Temp reached 200 degrees and started to print just fine.  Five mins later the spare hot end will not heat.  What are the chances of two heating cores going bad in the same 30 min window? 

I searched the forum and used the trouble shooting from the following post;

http://www.soliforum.com/topic/636/hot- … to-repair/

Following the procedures I checked the volts at the connector marked "H" (my machine it is marked "PT" but turns on and off with my extruder heat), the volts read 27.  I checked the volts at the extruder and I got the same reading of 27.  If it should be 12, is my machine pushing too much and that caused my heating cores to burn out?  If so how do I fix this issue?

SD2, Mac 10.8.3, Repetier 0.55

2 Reply by ronsii

  • ronsii
  • Member
  • Offline
  • From: PNW
  • Registered: 2012-10-28
  • Posts: 1,723

Re: Hot End Burned Out? (12v vs. 27v)

so how many volts are coming out of the power supply? connector on the bottom right of the main board.

3 Reply by bowvmi2001

  • bowvmi2001
  • Member
  • Offline
  • Registered: 2012-11-18
  • Posts: 23

Re: Hot End Burned Out? (12v vs. 27v)

It is also reading 27v.

4 Reply by elmoret

  • elmoret
  • Filastruder
  • Offline
  • Registered: 2012-10-11
  • Posts: 6,048

Re: Hot End Burned Out? (12v vs. 27v)

bowvmi2001 wrote:

It is also reading 27v.

Welp, there's your problem.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

5 Reply by bowvmi2001

  • bowvmi2001
  • Member
  • Offline
  • Registered: 2012-11-18
  • Posts: 23

Re: Hot End Burned Out? (12v vs. 27v)

Thanks for the feedback.  I ordered a new power supply and new heating cores.  Hopefully that will fix my problem and I can get back to printing.

6 Reply by elmoret

  • elmoret
  • Filastruder
  • Offline
  • Registered: 2012-10-11
  • Posts: 6,048

Re: Hot End Burned Out? (12v vs. 27v)

bowvmi2001 wrote:

Thanks for the feedback.  I ordered a new power supply and new heating cores.  Hopefully that will fix my problem and I can get back to printing.

Return those bad boys to Solidoodle, that's not right for you to foot the bill on!

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

7 Reply by danny

  • danny
  • Member
  • Offline
  • Registered: 2012-08-09
  • Posts: 322

Re: Hot End Burned Out? (12v vs. 27v)

good story to illustrate that you should confirm the fault before just swapping the part, (if you'd have seen the 27 volts then you wouldn't have put your spare good hotend on!)

Given the prices in the solidoodle store you'd have probably done better to have just gotten an ATX power supply from a computer shop and a heater cartridge type heater to replace the resistor

would have been an upgrade of parts (quality and capacity) for less money.

8 Reply by bowvmi2001

  • bowvmi2001
  • Member
  • Offline
  • Registered: 2012-11-18
  • Posts: 23

Re: Hot End Burned Out? (12v vs. 27v)

I got the new power supply and heating cores today.  I installed the new power supply and it is also reading 27v.  I tested my multimeter in one of my wall outlets and it read 119v.  Does anyone have any ideas?

Danny,
    What type of resistor would I need to get to fix the old cores.  I am not super smart with electronics, but I know enough to get myself in trouble.

9 Reply by mr_tim34

  • mr_tim34
  • Member
  • Offline
  • Registered: 2013-02-17
  • Posts: 111

Re: Hot End Burned Out? (12v vs. 27v)

Did you have your meter set to DC volts when you measured the 27volts? It's possible there is an AC component to the 12V line. Is it possible you were reading 27 millivolts AC? To make sure your meter is working measure a battery, AAA, AA, C or D all should read about 1.6V, a 9V should read a little over 9. Just a thought.

TiM

10 Reply by lawsy

  • lawsy
  • Moderator
  • Offline
  • Registered: 2012-08-13
  • Posts: 1,220

Re: Hot End Burned Out? (12v vs. 27v)

Some (cheaper) power supplies are not regulated and will read much higher when there is no load on them.

Are you measuring the voltage with nothing attached to the power supply?

lawsy's Website

11 Reply by bowvmi2001

  • bowvmi2001
  • Member
  • Offline
  • Registered: 2012-11-18
  • Posts: 23

Re: Hot End Burned Out? (12v vs. 27v)

Tim,
    I believe that I was making the mistake with my multimeter that you described.  I measured a AA battery and got 3v.  I switch the settings on the meter and then got 1.5v.  After I remeasured the power supply I got 12.6v.  I installed the new heating core and it has been printing for over a hour with no issues.  Maybe I just had two heating cores burn out on me within the same 30min window.

I am still interested in finding out what type of resistor to use in the heating core in order to fix the two bad cores that I now have.