Delta Smart Effector hotend temperature fluctuations

[mihaitintea]

This is in the 2-3 minutes right after last forum post. It looks like it is related to the nozzle tip ramming into some filament blobs (caused by imperfect filament flow, or variable filament quality)

I reset those H1 faults but it seems that every print session could be done only by manual human intervention every 5-10 minutes or so. Unless there is a way to lower the sensitivity which consists of the Delta Smart Effector board + the PT100 daughterboard + the PT100 sensor.

I am sure that the Duet firmware was designed to aid me to face the fire hazard -- who knows why a heater fault may occur ? -- but I see an additional reason for which all those "alien" heater H1 faults appear: the filament may not cost a ton of gold per spool. Which is perfectly the situation of 99.99 % of of the customers which buy the Duet board and the Delta Smart Effector.

That is why I need a way to tell the Duet board to ignore H1 heater faults unless those faults are 50% of the requested printing temperature, or worse.

Is there such a method to lower that PT100 chain sensitivity?

Thanks

[mihaitintea]

Hello

There were no solar flares yesterday. The problem is that the nozzle of the Delta Smart Effector hits various micro-obstacles on the printed object. Since the existence of those micro-obstacles cannot be avoided, we need to "deafen" the PT100.

I believe the sensitivity of the PT100 mechanism can be lowered with one or two ceramic capacitors. However I am not sure how it would be best:

a) One single capacitor between the two middle pins of the four pins at the PT100 daughterboard level ? (My PT100 sensor is 2-wire)

b) One single capacitor between the two PT100 pins on the Delta Smart Effector at the Delta Smart Effector pcb level ?

c) Two capacitors on the PT100 daughterboard: first capacitor between one middle PT100 pin and the daughterboard's GND, and the second capacitor between the other middle PT100 pin and the daughterboard's GND ?

Please can you tell which variant you think would be best, and if the 10 nF capacity is OK for the variant thought as best ?

Thank you

[Adrian52]

@mihaitintea I have been using the pt100/smart effector combination without problems. Following an earlier suggestion, I use stranded cat6 cable - two pairs for the pt100 and two pairs for the z probe. I did find the small connectors on the daughterboard a bit tricky (eyes not what they used to be) - maybe worth checking.

[dc42]

@mihaitintea said in Delta Smart Effector hotend temperature fluctuations:

Hello

There were no solar flares yesterday. The problem is that the nozzle of the Delta Smart Effector hits various micro-obstacles on the printed object. Since the existence of those micro-obstacles cannot be avoided, we need to "deafen" the PT100.

I believe the sensitivity of the PT100 mechanism can be lowered with one or two ceramic capacitors. However I am not sure how it would be best:

a) One single capacitor between the two middle pins of the four pins at the PT100 daughterboard level ? (My PT100 sensor is 2-wire)

b) One single capacitor between the two PT100 pins on the Delta Smart Effector at the Delta Smart Effector pcb level ?

c) Two capacitors on the PT100 daughterboard: first capacitor between one middle PT100 pin and the daughterboard's GND, and the second capacitor between the other middle PT100 pin and the daughterboard's GND ?

Please can you tell which variant you think would be best, and if the 10 nF capacity is OK for the variant thought as best ?

Thank you

I have already recommended option C on this forum. The recommended value is 100nF. I have verified that this fixes problems caused by noise being picked up from stepper motor cables etc. There is already a capacitor connected between the two middle pins.

Two other possibilities:

1. Grounding the hot end metalwork (so that the case of the PT100 sensor is grounded) may help.
2. If it is mechanical shock to the sensor that causes the fluctuations, the PT100 sensor may be faulty.

[mihaitintea]

@dc42 Hello

I applied option C, I just hope I identified correctly the GND on the PT100 daughterboard, please can you confirm from the picture below ?

Thank you