Rapido 2 thermistor not reading correctly (pt1000 on EBB42-with max31865)
After a full rebuild of my RR vc3.1 300, my thermistor now reads -237,5-ish (MINUS). I think it is caused by my own doing and am looking for some advise on how to proceed:
I am running a 3-wire hot end fan to monitor the functioning of this fan (curtesy of Andrew Ellis: https://ellis3dp.com/Print-Tuning-Guide/articles/useful_macros/hotend_fan_monitoring.html).
With the rebuild, I accidently put the fan's tachometer_pin wire in a 5V (probe) output of the ebb42 i.s.o. PB9. At first it all worked as before the rebuild. I heated the hot-end and got warnings for fan stoppage (as now is clear to me, as I did not wire it in correctly). I extruded some plastic and got a shutdown due to the hot-end fan not working (all as it should work!).
When I did a firmware restart I got a warning for the extruder being out of range. I lowered my min_temp and after that it started up but shows my extruder temp at high negatives.
I wired in a spare (identical) thermistor and that showed the same value.
I checked all the wiring and all seems fine.
So, I think I blew up something on the ebb42...?
- What are my options? (other than ordering a new EBB42-non Max31865, which I already did but needs to come from far-far-away)
- Can I wire the thermistor to other pins?
Appreciate all your thoughts and suggestions!
(to avoid the first reply being a ref to https://discord.com/channels/582187371529764864/1047086745415594044 I added the logs)
Full setup (I think this is all):
- Ratrig VC3.1-300 enclosed
- Manta M8P (1.0)
- EBB42 Max 31865 V1.1
- Orbiter 2.0 with Orbiter sensor
- Phaetus Rapido 2.0 UHF
- Ratos 2.1 RC3
Solution:Jump to solution
if so, you can use run the thermistor wires directly to the Manta and insert the jumper there. Then you set it up on the manta and make sure you have pullup_resistor: 2200 in the config.
11 Replies
Hello.
I assume you inserted the jumper on the EBB...
Solution
if so, you can use run the thermistor wires directly to the Manta and insert the jumper there. Then you set it up on the manta and make sure you have pullup_resistor: 2200 in the config.
that should work until you have the new EBB
Yes.
That is a super idea! Just two wires to the manta. The pullup resistor is already defined for the EBB42 (in the [extruder] section).
I am still confused every time, reading BTT's manual on how to config with pt1000 (2 wire) with max31865....
For the ebb42, I had connected to the TH0 port (so not to the 4 pin connector which reads pt1000) and placed the jumper and configured the dipswitches as per manual.
I still do not get why the 4-pin connector is there...
no need to use the MAX. it will only make everything harder.
Are you using the stock PT1000 on the Rapido?
If so, just run the wires to the Manta, insert the jumper and set it up on configurator.
the 4 pin connector is just for the 3 or 4 wire sensors. or PT100. For the PT1000 the th0 is more than enough
follow this wiring guide for the thermistor
https://os.ratrig.com/docs/boards/btt/manta-m8p
All, Appreciate the feedback! This will get me going agian untill the replacement EBB42 NON MAX31865 arrives.
Two remaining questions:
1. in the manual (I have actually read it, for a change) of the Manta is stated that I should add an additional resistor in parallel (I assume over the short-circuit pins? Beats me why... or parallel over the thermistor pins?). I have not seen this in the Wiring diagram or anywhere else. Do I need this?
2. It is mentioned that the readout is "far less accurate this way". What is "Far less"? is that one degree off (no problem for me) or 10 degrees off (big problem for me)
1. not sure, I haven't heard of any issues that needed this
2. I have actually had the opposite issue with my board. Using the MAX chip after many PID tunings (like 6-8) the temp would still vary by =/- 2 degrees! Once I switched to a plain thermistor port, the exact same thermistor and a new PID tuning had the temp stay +/- 0.1 degrees
1. The jumper is to activate the correct pullup resistor. It is near the thermistor plug in the board.
2. With the MAX chip, supposedly it is a bit more accurate. But the major difference is refresh rate. And that has nothing to improve in 3d printers…
Thanks Gents! crimping my temp.wire as we speak!
Up and running again!!! Had me going around in circles for a while, until I figured out that I needed to reconfigure sensor_pin: PA1,... (whereas I had reconfigured heater_pin: PA1)