weird RD3 behavior

Robert Y

New member
Noticed when starting a cook this afternoon that the temperature output from the rd3 was a bit off. Once it was plugged in the temperature dropped steadily 245 degrees in a linear fashion down to 88.2 degrees. I confirmed with my thermopen that the pit temp was around 150 degrees. I took the thermocouple and plugged it directly into the heatermeter and the temperature then jumped to 158.

So it seems that my rd3 might be having some issues with recording the temperature and sending it to the heatermeter. I'm not sure this is related but I also noticed that the servo doesn't appear to be working either, the fan works fine. Haven't had luck finding a real mg90s but will keep looking.

Anyone have any idea where to start looking to see if I can isolate where my issue might be?
 

Robert Y

New member
well I take that back, it seems as though the servo isn't working and the fan appears to be dead as well.
 

Bryan Mayland

TVWBB Honor Circle
Is it one of the RD3 with the external thermocouple board? I'd say start with checking the easiest stuff first. Is there a signal at the RJ45 jack on the HeaterMeter at BLOW/GND, 5V/GND, and SERVO/GND. At 100% output they should be 12V. 5V, and non-zero respectively. Also you can verify in the webui that the configuration didn't get mixed up somehow and set the maximum output to 0% or something.
 

Robert Y

New member
I believe it is one of the RD3's with the external thermocouple board. So I noticed last night that there was no blinking on the cat5 connection at the heatermeter. Today I checked the cable with one of my testers and it came back faulty. So I checked another cable that I had made earlier for another project that cable was fine. Still though, unfortunately no blinking lights on the heater meter and no reaction from the servo or the fan.

No changes in the webui that would make me think it got switched.

I have a m12 battery adapter that I might be able to use to jump the fan and see if the fan works. If it does I'm thinking that it's likely the board unfortunately.
 

Robert Y

New member
Just jumped the fan with the m12 battery adapter and it started right up. It looks like it's something with the board unfortunately.
 

Bryan Mayland

TVWBB Honor Circle
What lights blink on the HeaterMeter? If you're referring to the 3 LEDs on the LCD/Button board, if they're still in their default configuration the green one should be on if output is > 0%, and the red one should be on if the output is 100%. If those aren't on then HeaterMeter doesn't think it should be driving the output at all.

If you mean the blinking LEDs on the Pi, then those would indicate a boot failure on the Pi, but the HeaterMeter should still operate (unless the power is the bad part).
 

Robert Y

New member
The blinking lights on the cat5 connector on the heatermeter, like the lights that blink when there's data moving. I know the led's on the heater meter are still on and acting as if the heatermeter is driving an output.
 
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Bryan Mayland

TVWBB Honor Circle
So you're saying that there's no blinking lights on the wired Ethernet connector when you plug in the blower into the other RJ45 jack? That is, you have wired Ethernet plugged in and the lights blink, but when you plug in the second Ethernet cable for powering the fan/damper, the Ethernet lights go out? To be clear, the blower/damper ethernet cable can not go into the Pi's Ethernet network jack (well, it can go into it but it won't do anything).
 

Robert Y

New member
<--- all of a sudden very nervous that his problems are caused completely by his ineptness....will need to check in g a moment....
 

Robert Y

New member
well....there is likely an unknown amount of times I quietly cursed the heatermeter for not reading a pit probe on the extension for the rd3 blower, when in actuality I had it plugged into the wrong ethernet port. That also means there's been a few cooks when there was no fan running or servo running...
 

Bryan Mayland

TVWBB Honor Circle
Haha whoops! The RJ45 was chosen for the output jack just due to the ubiquity of Ethernet cables but, yeah, there is the problem that there's also another jack on the HeaterMeter that the plug fits into. I've definitely done it myself a few times as well. At least it is an easy fix once you realize what's wrong.
 

RalphTrimble

TVWBB Diamond Member
$hit happens... LOL
Nothing blinks in the CAT5 jack on the HM board ever, that was the first clue something was odd about your situation. I agree having a CAT5 jack on the blower/servo does create the possibility this could happen, but it's rare... and I bet you'll never make that mistake again!
 

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