I have just put my printer together, done all the tests as per the manual, however I can’t get the heat printbed to heat up (50oC) at all. I have check all connections and are all ok.
Any Ideas
Can you unplug the connector on the board and measure the resistance of the heated bed (on the connector)?
What temp does repetier show for the heatbed?
Heat bed show 0 the box next to it shows 50.
I check the res and it all good. The system show T:15.7/0.0 B:0.0 /50.0 @:0
[quote=“x4paul”]Heat bed show 0 the box next to it shows 50.
I check the res and it all good. The system show T:15.7/0.0 B:0.0 /50.0 @:0[/quote]
You mean the box for setting the temp?
If repetier shows 0°C it is almost sure you have a short in the thermistor wiring,
as the thermistor resistance decreases with rising temperature.
Or did you change something on the firmware?
That’s correct
I have just taken the thermistor off and re soldered it if I put a voltage meter on it show voltage on one side but not on the other.
I have also updated the firmware as told to do
Then you have burnt out your thermistor i think.
Happened to me too. The smd thermistors easily go to heaven if soldered too hot. 
Look in the bags for a spare thermistor for the extruder. (the axial wired type)
My printer had one in spare when it was delivered.
You can solder that to the heatbed and try again.
For me that worked perfectly. (just make sure the glass case of the thermistor touches the heatbed closely for correct temp readings)
[quote=“ichbinsnur”]Then you have burnt out your thermistor i think.
Happened to me too. The smd thermistors easily go to heaven if soldered too hot.
Look in the bags for a spare thermistor for the extruder. (the axial wired type)
My printer had one in spare when it was delivered.
You can solder that to the heatbed and try again.
For me that worked perfectly. (just make sure the glass case of the thermistor touches the heatbed closely for correct temp readings)[/quote]
I have Checked and there is no spare in the box.
Well is there away I can check the thermistor?
If not how do I get a new one I’ve just spoke to the place where I got the printer from but they say they cant get the part.
Is there any other part I can use in its place.
Disconnect the heatbed and measure the resistance of the thermistor.
It should read about 100kOhms at room temp.
[quote=“ichbinsnur”]Disconnect the heatbed and measure the resistance of the thermistor.
It should read about 100kOhms at room temp.[/quote]
Done that and got no reading at all, so I have been an order anew one but it wont get here till early Jan.
On the other hand I have tried to measure the voltage going to the board and am getting nothing from the red and brown or from the other wires.
If the thermistor is open circuit the firmware will not start heating for overtemp protection.
As i said, just try a axial wired thermistor like the one used on the extruder.
They should be easy to get, and work at least for the time till you get a new smd one.
Look again in your parts, sure there isn’t a extruder thermistor in spare?
Thanks for the help I have got a spare extruder thermistor and its working fine.
Danka
Nice to hear it works.
Happy printing!