Heated bed issue with Temp sensor working

[flyguy 0]

Hello, I am having some issues getting a 2nd temperature sensor working for a heated bed.

I bought this sensor.

http://ultimachine.com/content/thermistor-100k

I added a 4.7k Resistor to R4 Yellow-Purple-Red-Gold is the resistors color

Modified Marlin

Configuration.h

// 6 is EPCOS 100k

#define TEMP_SENSOR_0 -1

#define TEMP_SENSOR_1 0

#define TEMP_SENSOR_2 6

#define TEMP_SENSOR_BED 0

Uploaded to the Arduino the new configuration

NTC thermistors Series/Type: B57560G, B57560G1

Connected to the Temp 3 terminal on the board. GND and SIG leaving the 5v empty. (see attached picture)

 

https://docs.google.com/open?id=0B3IYX8 ... 3dPeVRMNWM

Connected with printrun USB connected and the power on

My problem is it does not work.

M105 returns

SENDING:M105

ok T:34.2 /0.0 B:0.0 /0.0 @:0 I assume these are temp readings 2 and 3

When I set the Heater to 200

I get this

SENDING:M105

ok T:35.6 /200.0 B:0.0 /0.0 @:127

@220

SENDING:M105

ok T:154.2 /220.0 B:0.0 /0.0 @:127

@100

SENDING:M105

ok T:191.4 /100.0 B:0.0 /0.0 @:0

I only have 1 heater connected and it is attached to the nozzle / hot end

Any idea or help would be greatly appreciated.

Thank you,

Brian

[antiklesys 3]

Missing picture.

You need to connect it this way:

+5v --> thermistor ----L---> 4.7k resistor ---> gnd

and you plug the L connector in the SIG.

The thermistor will then be a tension partitioner and will vary it's resistance when the temperature changes. By reading the tension between the thermistor and the resistor (in point L) you will be able to relate it to what temperature is being read.

[flyguy 0]

Here is the image of the connection to the board.

https://docs.google.com/open?id=0B3IYX8 ... 3dPeVRMNWM

 

[flyguy 0]

I thought you solder the 4.7k resistor onto the controller board.

"If you solder a 4.7kOhm resistor to the Ultimaker PCB (R4 if you use TempSensor3 or R21 if you use TempSensor2) you can measure the temperature of the bed using a Thermistor more info. "

http://wiki.ultimaker.com/Heated_Bed#Sensor

http://wiki.ultimaker.com/File:Bedconnection.png

If I understand your asci schematic correctly, would this be the proper way to connect the temp sensor ?

https://docs.google.com/open?id=0B3IYX8 ... W11c21EZVk

 

Missing picture.

You need to connect it this way:

+5v --> thermistor ----L---> 4.7k resistor ---> gnd

and you plug the L connector in the SIG.

The thermistor will then be a tension partitioner and will vary it's resistance when the temperature changes. By reading the tension between the thermistor and the resistor (in point L) you will be able to relate it to what temperature is being read.

[flyguy 0]

So my issue was that I did not have a 2nd resistor in place.

One resistor goes on the Ultimaker PCB and the other spans between the thermistor terminal

This page

http://reprap.org/wiki/Temperature_Sens ... tor_Values

and this page helped a lot

http://hydraraptor.blogspot.com/2007/10 ... y-way.html

Also this schematic

http://reprap.org/wiki/File:Cache-28487 ... 7b1d24.jpg

In the Jpg above R2 is soldered on the Ultimaker PCB and R1 needs to be an additional resistor.

[Daid 303]

I think the optional 4.7k resistor on the Ultimaker PCB actually IS the resistor you need to connect between the 'signal' and the ground. So with that resistor in place you just need to connect the thermistor between +5 and SIG.

If I look at this picture from you:

https://docs.google.com/file/d/0B3IYX8i ... RMNWM/edit

then you have connected the thermistor between GND and VCC. Not sure where you got the pinout from, but on the board it clearly reads GND +5V SIG.