Convertion Raise3D N2 vers Klipper heatbed problem temperature

[RB3D]

Basic Information:

Printer Model: Raise3D N2
MCU / Printerboard:
klippy.log

klippy-2.log (426.8 KB)

Hello, with Marin, the Raise3D has this type of probe
// 8 is 100k 0603 SMD Vishay NTCS0603E3104FXT (4.7k pullup)

I have tried all the Klipper probes

#"EPCOS 100K B57560G104F",
# "ATC Semitec 104GT-2", "ATC Semitec 104NT-4-R025H42G", "Generic
# 3950","Honeywell 100K 135-104LAG-J01", "NTC 100K MGB18-104F39050L32",
# "SliceEngineering 450", and "TDK NTCG104LH104JT1"

and I still have the same temperature (see screenshot)

As soon as I fixed this problem, the printer works perfectly with Klippers.

I saw that you could customize your probe, do you think this is possible?

Thank you

[RB3D]

Why does no one answer when all the other conversations have at least 1 answer?

[LifeOfBrian]

Sometimes it takes some time until somebody is answering.
Don’t be so impatient!
Do you mean Marlin with Marin?

You can define custom thermistors in Klipper:
https://www.klipper3d.org/Config_Reference.html#thermistor

You can measure the resistance of your thermistor while heating it and using another well known and defined thermistor as reference being connected to the printers motherboard instead of the original one.
Our you’ll search the internet for a data sheet of that thermistor and use three resistance values for the respective config section.
Afterwards you can further optimize/calibrate the temperature curve via an external temperature sensor.

[RB3D]

Yeah, sorry for the impatience.
I could already see the printer working with Klipper

Thanks for your answer. It does not make me particularly happy because I feel that it could be long but there seems to be some hope not to change the motherboard and the heating bed?

The temperature is doubled I would just like to divide /2 but I guess it’s not that simple.

So I don’t know where to start looking for information.

Can you help me?

Do you think I can cut this blue wire and put the resistor like in this post?
https://forum.raise3d.com/viewtopic.php?f=4&t=11269&p=37178#p37178

Here are some conversation links about this board and its motherboard

Raise3D Heated Bed thermistor and Duet2Wifi

https://support.raise3d.com/Pro2-Series/motion-controller-board-installation-4-677.html

[RB3D]

I have several options:

1/ Change the resistor and or the thermistors? link

2/ Change the bed and put a heating mat, such as Voron.
In this case, it will be necessary to connect the two cables of the heating mat on GND and Signal?

Hoping that someone will give me some clues to move forward.

Dumb question, the PID has nothing to do with the temperature display problem?

[RB3D]

I found this interesting but difficult for me to find. I add the schematic of the map. If someone can help me to find the right temperature value.
link

Those temperature inputs use a pull up resistor expecting a thermistor to pull down and the voltage across the thermistor used to calculate the temperature. In your case the pull up is causing an unwanted offset in your signal. For an externally amplified signal you don’t want the pull up resistor. Neither of the files you linked to are the full electrical schematics for me to know for sure but on the ramps boards the pull-ups for the temperature inputs are internal to the microcontroller and are software controlled. In your klipper config see if there is a “^” next to the pin definition and remove it. That is the symbol to enable the pull up on the pin. Without the pull up it should be correct. If it is not software controlled there then the pull up could be a physical resistor on the board that would need to be removed.

[RB3D]

https://forum.raise3d.com/viewtopic.php?f=4&t=2110&p=16509&hilit=adc#p16507

Schematics reverse engineered for motion board were detailed here and a crude but correct overall system layout was posted by me ages ago.
viewtopic.php?f=6&t=1203&p=10941&hilit=schematic#p10941

As you can see at the motion board, I have diagramed the HBP 3 wire thermistor connector to the heated bed.

If you measure the sense pin to ground (at the motion board, the outer 2 wires) at room temp (23C reported on the LCD) the sense pin was 4.45V with a working heated bed thermistor plugged in.
If I unplug the cable from the from the motion board (no heated bed thermistor connected) and ensure power cycle the printer, the reported temp is 168C.

So, what you may have is a broken HBP connector or thermistor circuit at the heated bed.

Just did more testing.
The HBP is actually a 10K pullup, not 4.7K as I stated in the previous reply.
So at room temp you should get the following reading on 3 pin HBP connector.
Between the outer 2 pins= roughly 101-102K Ohms
Between pins 1-2 roughly 112K and pins 2-3 10K Ohms
This is at the 3Pin connector at the motion board.

Again, the HBP thermistor circuit is quite simple at the heated bed.
You have 3 pins or wires.
1 is ground, one is 5V, and the other is the signal between 5V and ground that varies with temp.

Now, being dead honest, I’m looking at my new N2 Plus and the wire colors, and what I would consider standard wire colors is not matching to the schematic. I am a bit confused by this. By that, I would generally wire Red to 5V, Black as GND, and Blue as the sensing wire. Again, just telling you this that if you too often work with DC wiring, be aware of this.

Again, on my printer, Red is connected to the pin labeled sense, and Blue is to the 5V pin, and Black is still GND at the motion board.

So, with cable unplugged and checking the HBP itself for resistance
Red to Blue is 10K Ohms
Black to Blue is roughly 114K Ohms
Black to Red is roughly 104K Ohms

With the connector plugged into the mainboard, we measure voltage.
Black(GND) to Blue(5V) is 5V (mine registered 4.98V)
Black (GND) to Red (S) is measuring the sense pin, so at room temp 4.45V

Again, this assumes your colors match mine but I also told you the pin names as diagrammed.

[RB3D]

@LifeOfBrian

You can measure the resistance of your thermistor while heating it and using another well known and defined thermistor as reference being connected to the printers motherboard instead of the original one.
Our you’ll search the internet for a data sheet of that thermistor and use three resistance values for the respective config section.
Afterwards you can further optimize/calibrate the temperature curve via an external temperature sensor.

Hi, I’m back. I’m finally starting to understand a little bit what I have to do.
However, I don’t understand the calculation I have to do to find the R2 R3 values when the tray is hot? Because I put this value of 50 000 approximately.

When I measure GND+Signal = 114,1K
When I measure GND+5V= 124K
When I measure Signal + 5V =10K
When I change the value resistance1: 50000.0 the temperature of the bed corresponds to the temperature of the head.

If someone has a few minutes to write me the calculation. Best ragrds

[thermistor bed_rn2]
temperature1: 25.0
resistance1: 50000.0
#temperature2: 150.0
#resistance2: 1366.2
#temperature3: 250.0
#resistance3: 168.6
beta: 3950

[heater_bed]
heater_pin: PH6
sensor_type: bed_rn2
sensor_pin: PK3
control: watermark
min_temp: 0
max_temp: 120

[RB3D]

Just to explain to possible users to simply put :

[thermistor bed_rn2]
temperature1: 25.0
resistance1: 47000.0
beta: 3950

The temperature fits perfectly to the extruder.
Then I did a PID.
The bed works perfectly well.

I still don’t understand the calculation but it works, that’s the main thing!