
My Hot End is not heating up!
- AndThenSome09
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My Hot End is not heating up!
My hot end is not heating up. everything else has passed the testing but that
Could it be the wires I used are too small? I used the included wire but it did seem to be smaller than what I used for the extruder extension.

Re: My Hot End is not heating up!
Take this with a grain of salt since I'm still building mine, but think basic electronics. Disconnect the hot end wiring from the Rambo and then take your meter and measure the resistance across the 2 resisitors. If it's infinite, you have an open resistor or a bad joint in the wiring. If it's zero, you have a short somewhere. If you get something around 3.4 ohms, it's good. Start there...
Too small a wire could be an issue, but it would probably just make heating slow unless it gave out completely but that seems unlikely.
Too small a wire could be an issue, but it would probably just make heating slow unless it gave out completely but that seems unlikely.
Re: My Hot End is not heating up!
I'd also check to make sure your in the right heat control on the Rambo. Also look at the temp in your host. If you turn the bed on and the temp goes down then you have it wired backwards.
Re: My Hot End is not heating up!
No matter how you wire the thing, it's not going to *COOL* when you turn it on. That's just nonsense.2jayzman wrote:I'd also check to make sure your in the right heat control on the Rambo. Also look at the temp in your host. If you turn the bed on and the temp goes down then you have it wired backwards.
I'm surprised nobody has advised checking to see if the heater MOSFET's LED is turned on and to check the fuses.

g.
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- Eaglezsoar
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Re: My Hot End is not heating up!
geneb wrote:No matter how you wire the thing, it's not going to *COOL* when you turn it on. That's just nonsense.2jayzman wrote:I'd also check to make sure your in the right heat control on the Rambo. Also look at the temp in your host. If you turn the bed on and the temp goes down then you have it wired backwards.
I'm surprised nobody has advised checking to see if the heater MOSFET's LED is turned on and to check the fuses.
g.
He had another thread running here: http://forum.seemecnc.com/viewtopic.php ... 993#p22993
He was advised to check the fuses, I don't know why he opened a second thread.
- AndThenSome09
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Re: My Hot End is not heating up!
Sorry guys, I posted this in my build log thread and here also, thought I should maybe post it in troubleshooting to get faster answers, I'll stick to one place for all future posts as not to have any confusion.
Thank you guys, I pulled out my multimeter as suggested and started testing along the connection, came to the hot end and it wasn't giving any resistance reading, hmm I thought so I took it all apart to realize, much to my embarrassment
, that I had twisted the resistors with themselves so no wonder it wasn't heating up!
lol, needless to say it made me feel pretty stupid I don't even know why I'm admitting it but oh well, share in my success as well as failures I guess! In my defense, I remember the night I was doing the hot end and it was really late like on to the next morning so I was probably just a little out of it I'd say
Luckily I hadn't taken the RTV out yet or anything so I just twisted them correctly and connected the little pig tail connector on and I was back in business!!
yeah! 
Thank you guys, I pulled out my multimeter as suggested and started testing along the connection, came to the hot end and it wasn't giving any resistance reading, hmm I thought so I took it all apart to realize, much to my embarrassment





- Eaglezsoar
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Re: My Hot End is not heating up!
Hey, it happens to us all. At least you are man enough to admit that you make mistakes.AndThenSome09 wrote:Sorry guys, I posted this in my build log thread and here also, thought I should maybe post it in troubleshooting to get faster answers, I'll stick to one place for all future posts as not to have any confusion.
Thank you guys, I pulled out my multimeter as suggested and started testing along the connection, came to the hot end and it wasn't giving any resistance reading, hmm I thought so I took it all apart to realize, much to my embarrassment, that I had twisted the resistors with themselves so no wonder it wasn't heating up!
lol, needless to say it made me feel pretty stupid I don't even know why I'm admitting it but oh well, share in my success as well as failures I guess! In my defense, I remember the night I was doing the hot end and it was really late like on to the next morning so I was probably just a little out of it I'd say
Luckily I hadn't taken the RTV out yet or anything so I just twisted them correctly and connected the little pig tail connector on and I was back in business!!
yeah!
Re: My Hot End is not heating up!
Just to clarify, the actual physical temperate didn't go down. I had it wired backwards on my first build and the host temp indicated 25C to 21 C when I activated the bed, turned it off found my fault and fixed it. Bed was at room temperature.
Re: My Hot End is not heating up!
It reminds me of the legendary story about the IT tech comes into fix a user's computer problem only to find they'd plugged the power strip into itself.

g.



g.
Delta Power!
Defeat the Cartesian Agenda!
http://www.f15sim.com - 80-0007, The only one of its kind.
http://geneb.simpits.org - Technical and Simulator Projects
Defeat the Cartesian Agenda!
http://www.f15sim.com - 80-0007, The only one of its kind.
http://geneb.simpits.org - Technical and Simulator Projects
Re: My Hot End is not heating up!
When I install the power supply I'll take video. Maybe ghosts came in the room. Maybe I'm just a big liar. I know what I saw.