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Heated Bed Not Very Heated
Posted by erkall77
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Heated Bed Not Very Heated July 13, 2014 08:46PM |
Registered: 11 years ago Posts: 11 |
Hey guys.
I have got all the motors to work and everything seems to be up to par.
However, when I tested heating the hot end and the heat bed, only the hot end reached the set temperature.
The heat bed maintained a temperature of 27-28 degrees.
I have checked the connection of the wires numerous times but it still doesn't heat the bed.
Does anybody know what the problem may be ?
- K
I have got all the motors to work and everything seems to be up to par.
However, when I tested heating the hot end and the heat bed, only the hot end reached the set temperature.
The heat bed maintained a temperature of 27-28 degrees.
I have checked the connection of the wires numerous times but it still doesn't heat the bed.
Does anybody know what the problem may be ?
- K
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Re: Heated Bed Not Very Heated July 13, 2014 10:57PM |
Registered: 13 years ago Posts: 1,320 |
What electronics do you use and how have you connected power to it. I've seen it where people who have a RAMPS card do not hook up both power rails. The 5 amp rail powers everything but the heated bed; the 11 amp rail powers the bed. If this is what yo have and you did not connect power to the 11 amp input, then this is your problem.
Are you seeing and led activity near the output for the bed?
Are you seeing and led activity near the output for the bed?
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Re: Heated Bed Not Very Heated July 14, 2014 07:11PM |
Registered: 11 years ago Posts: 11 |
I used RAMPS 1.4 and Sprinter firmware.
I also used a 12 Volt power supply.
I dont know what the 5 amp rail or 11 amp rail is.
I just hooked up the power supply as the wiki told me to.
Could you clarify how I distinguish the 11 amp rail from the 5 amp rail ?
Also, yeah. I think I see LED activity by the output for the bed, but it could be the output for the hot end.
Any ideas?
- K
I also used a 12 Volt power supply.
I dont know what the 5 amp rail or 11 amp rail is.
I just hooked up the power supply as the wiki told me to.
Could you clarify how I distinguish the 11 amp rail from the 5 amp rail ?
Also, yeah. I think I see LED activity by the output for the bed, but it could be the output for the hot end.
Any ideas?
- K
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Re: Heated Bed Not Very Heated July 14, 2014 08:29PM |
Registered: 13 years ago Posts: 1,320 |
If you look at the picture here you can see the power connections at the lower left, and you can see that 1 is marked 5 amps and 1 is marked 11 amps. This picture shows that connected in parallel to the same power supply - which is possible if the power supply is capable of delivering 16 amps (actually I'd go for at least 20 amps just to have a margin for error).
Both connections must be made. As I said, the 11 amp rail is for the bed only. The 5 amp rail is for everything else,
Both connections must be made. As I said, the 11 amp rail is for the bed only. The 5 amp rail is for everything else,
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Re: Heated Bed Not Very Heated July 14, 2014 10:31PM |
Registered: 11 years ago Posts: 11 |
So, how do I tell if my power supply has the correct Amp value ?
I attached a picture of my power supply connection.
I'm not sure if its the way you said.
I don't get what the green and orange wires are in the image you sent.
Do you know what they are for, or are those unnecessary ?
- K
I attached a picture of my power supply connection.
I'm not sure if its the way you said.
I don't get what the green and orange wires are in the image you sent.
Do you know what they are for, or are those unnecessary ?
- K
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Re: Heated Bed Not Very Heated July 14, 2014 10:37PM |
Registered: 11 years ago Posts: 241 |
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Re: Heated Bed Not Very Heated July 15, 2014 02:37AM |
Registered: 13 years ago Posts: 1,320 |
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Re: Heated Bed Not Very Heated July 15, 2014 03:18AM |
Registered: 11 years ago Posts: 1,518 |
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Re: Heated Bed Not Very Heated July 15, 2014 10:18AM |
Registered: 12 years ago Posts: 553 |
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Re: Heated Bed Not Very Heated July 15, 2014 01:12PM |
Registered: 11 years ago Posts: 11 |
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Re: Heated Bed Not Very Heated July 15, 2014 01:25PM |
Registered: 12 years ago Posts: 553 |
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Re: Heated Bed Not Very Heated July 15, 2014 02:03PM |
Registered: 13 years ago Posts: 1,320 |
Yes - the PSU supplies enough amperage. That's why I suggested that you move to the output side of the ramps. Check the voltage at the output of the ramps board, and at the terminals on the bed. Check the wire gauge running to the bed. Check the bed resistance. Check for good solder joints where the wires connect.
I would also echo tjb1 - you should move to a more modern firmware.
Also, show us pictures of the bed connection.
I would also echo tjb1 - you should move to a more modern firmware.
Also, show us pictures of the bed connection.
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Re: Heated Bed Not Very Heated August 06, 2014 05:35PM |
Registered: 11 years ago Posts: 11 |
Alright I will think about changing firmware.
But, I checked the output and the solder joints with a multimeter.
The voltage was 12.26v at both points.
The current was 10 amps.
And the resistance was zero.
So, I still dont understand what the issue is since it seems to be receiving about the right amount of current. Also, the voltage drop seems like its right, but let me know what you guys think.
I attached some photos of the solder joints. The second photo is a side view and its a little bit difficult to see.
- K
But, I checked the output and the solder joints with a multimeter.
The voltage was 12.26v at both points.
The current was 10 amps.
And the resistance was zero.
So, I still dont understand what the issue is since it seems to be receiving about the right amount of current. Also, the voltage drop seems like its right, but let me know what you guys think.
I attached some photos of the solder joints. The second photo is a side view and its a little bit difficult to see.
- K
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Re: Heated Bed Not Very Heated August 06, 2014 06:43PM |
Registered: 13 years ago Posts: 1,171 |
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Re: Heated Bed Not Very Heated August 07, 2014 03:00PM |
Registered: 11 years ago Posts: 11 |
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Re: Heated Bed Not Very Heated August 07, 2014 04:28PM |
Registered: 13 years ago Posts: 1,320 |
IN a series, or in parallel? I'm not familiar with that heated bed, but it seems to me you'd want parallel. In a series, you're basically only getting half of the voltage to each side of the board, and you won't get the heat output that you need.
Can you show us the photo you used for guidance as well as a better shot of the connection?
Can you show us the photo you used for guidance as well as a better shot of the connection?
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Re: Heated Bed Not Very Heated August 08, 2014 05:01PM |
Registered: 11 years ago Posts: 11 |
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Re: Heated Bed Not Very Heated August 08, 2014 07:47PM |
Registered: 13 years ago Posts: 1,320 |
I'm assuming terminal 1 is common, and 2 and 3 are the two halves of the board. They're wired in parallel.
It's hard to see, but the wire going between 2 and 3 appears to be small. Is that the same gauge as the other wires in the photo? You're carrying a significant amount of current through this wire. I guess you could go as small as 20 gauge, but I'd recommend 18. Not sure what yours is. (I'm not just talking about the small bit between 2 and 3 - I'm talking about the wire all the way back to the RAMPS).
Edited 1 time(s). Last edit at 08/08/2014 07:50PM by jbernardis.
It's hard to see, but the wire going between 2 and 3 appears to be small. Is that the same gauge as the other wires in the photo? You're carrying a significant amount of current through this wire. I guess you could go as small as 20 gauge, but I'd recommend 18. Not sure what yours is. (I'm not just talking about the small bit between 2 and 3 - I'm talking about the wire all the way back to the RAMPS).
Edited 1 time(s). Last edit at 08/08/2014 07:50PM by jbernardis.
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Re: Heated Bed Not Very Heated August 08, 2014 09:11PM |
Registered: 11 years ago Posts: 11 |
My hot end is wired with the same gauge wire as the heated bed.
Plus the hot end is heated to a higher temperature.
And yet, the hot end heats up perfectly.
So, could the wire gauge still be the problem?
I think the wire gauge is 20 though.
Also, the wire going between 2 and 3 is the same wire that goes to 2.
Is that a problem?
- K
Plus the hot end is heated to a higher temperature.
And yet, the hot end heats up perfectly.
So, could the wire gauge still be the problem?
I think the wire gauge is 20 though.
Also, the wire going between 2 and 3 is the same wire that goes to 2.
Is that a problem?
- K
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Re: Heated Bed Not Very Heated August 08, 2014 10:27PM |
Registered: 12 years ago Posts: 553 |
Quote
erkall77
My hot end is wired with the same gauge wire as the heated bed.
Plus the hot end is heated to a higher temperature.
And yet, the hot end heats up perfectly.
So, could the wire gauge still be the problem?
I think the wire gauge is 20 though.
Also, the wire going between 2 and 3 is the same wire that goes to 2.
Is that a problem?
- K
The hotend draws less than half the current that the bed does, you need to size your wire for 11 amps. 20 AWG will work for carrying 11 amps but it is right at the maximum for that wire. You should use 18 AWG or lower since the wiring will not be entirely ventilated.
[www.powerstream.com]
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Re: Heated Bed Not Very Heated August 08, 2014 10:41PM |
Registered: 13 years ago Posts: 1,320 |
yes - what tjb said.
The resistance of the hot end is higher than that of the bed so it draws less power. Just look at the fuse configuration. One 11 amp fuse protects the heated bed only. The 5 amp fuse protects 5 or 6 steppers, 1 or 2 hot ends, and perhaps fans. The wire gauge needs to be appropriate for the current draw.
When your bed heat is on, do the wires themselves start to warm up? If they do, then that is a clue that they are undersized.
Edited 2 time(s). Last edit at 08/09/2014 02:21PM by jbernardis.
The resistance of the hot end is higher than that of the bed so it draws less power. Just look at the fuse configuration. One 11 amp fuse protects the heated bed only. The 5 amp fuse protects 5 or 6 steppers, 1 or 2 hot ends, and perhaps fans. The wire gauge needs to be appropriate for the current draw.
When your bed heat is on, do the wires themselves start to warm up? If they do, then that is a clue that they are undersized.
Edited 2 time(s). Last edit at 08/09/2014 02:21PM by jbernardis.
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Re: Heated Bed Not Very Heated August 09, 2014 10:47PM |
Registered: 11 years ago Posts: 11 |
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