The big ELECTRONICS topic

Hi Guys,

I’ve been around now for a couple of months and I see a lot of the same questions related to electronics.
In this topic I would like to answer some of these questions.
In general its not complicated to assemble the electronics, just always be careful and don’t to stupid things 😊

The awnsers to the following questions will be in the replys down
– How much energy do the machines consume?
– Schematics for all the machines
– What parts do you need, and where do you buy them
– Tips and tricks
– decapping thermocouple
– wago connectors
– electronics of others

feel free to ask questions or suggestions for things i forgot 🙂

– How much energy do the machines consume?
This highly depends on the situation, but I can give an indication:

1-2kW so between 1000W and 2000W continuous

At warmup 900w from the bandheaters at maximum
When it is warm it drops to 400-600w
All of this is highly dependent on the room temperature, ventilation, isolation etc.

Same as the injection but then with an extra motor
At warmup a maximum of 900w from the bandheaters
When it is warm it drops to 400-600w + the power of the motor (roughly 300w)
All of this is highly dependent on the room temperature, ventilation, isolation etc.

Depends on the oven you buy, most of the time these are rated for 2000w, once it’s warm it will drop
All of this is highly dependent on the room temperature, ventilation, isolation etc.

yeah, a good mount definitely makes things better but if you spent a few more $$ on it – a good auto-tuning will determine the delay (ie : distance from sensor/heatband cool down & heatup, etc…) to avoid overshooting. In PID terms – it is the ‘integral’, ‘differential’ and ‘hysteresis’ which is being set by the tuning process . However, PP wise – you have often multiple heat bands with up to 10 cm in between – you want to measure the temperature in between and not too close to the heatband to get a good average. Apparently the RexC100 has a pretty poor auto-tuning nor you can set these parameters.

How well and where the thermocouple is mounted is an important factor in how well the PID works. I’m using the cheapest REX-C100 clones that don’t have tunable PID and they generally go straight to temperature. It helps that my tube is aluminum and the thermocouple has its own clamping block.

update: there is an auto-tuning function on the REXC100 :
1. Hold SET button for 4 seconds, til ‘ALI’ appears
2. Press SET button again, something like ATU should appear
3. Press ‘UP’ so it shows ‘1’ for auto-tuning’ active
4. Press SET again
5. wait for 10 secs til it goes out of settings by self, or hold SET button again for 3 secs

Now the AT LED should blink whilst reaching the target temperature. It will overshoot by the usual 20-30 degcs a few times and the settles on the target temperature. The auto-tuning process may last up to 30 minutes – depends on your heatbands and sensoring.

Conclusions: it should be better in holding on target after auto-tuning but it will still overshoot by up to 30 degs… Still, I recommend the Inkbird ITC 100 VH and I updated all wiki pages about it.

As I heard, some people have to much overheating due to cheap PID controllers, up to 20-30 degrees. As I have seen, people folks use the REX100 and I can confirm that this controller is actually pretty bad –  not just in production – as machine builder. I am actually surprised that even some machine builders uses this controller but still charge 2000 Euro for an injector – you can get a pro mill for the same price btw. – quite a game changer for most of us …

Anyways,  I’ve done some excessive tests on various PID controllers now and the winner is the INKBIRD – ITC 100V or 100R if you intend to extend your system at some point for automation. The very controller has also quite some extra safety features – software and hardware side. It performs very well ! The max. overheat I had on this one was 1.5 deg c the first time, and the second time 0.8. and it keeps the target temp. with +/- 0.9 deg c.

It also comes with a bunch optimization parameters which allows you tuning. The terminal screws are good quality too, same for the manual. The price : 34 Euro and it worth every penny.

I am updating the wiki. @davehakkens or however is in charge for customer protection and quality control, would be great you point this out somewhere. As often, we would be more happy and sleep better to let people know the better way instead of keeping everything artificially low and cheap.

thanks a lot.

The situation is this: one of the controllers works fine with any of the other components, while the other one heat up the bands way too fast (undependant of wich SSR or heatband i use.) When i checked how many amps each of the controllers drew, they both showed 0,75A when the SSR was active, wich makes this whole problem a headache.

The controller that overshoots have all the connection screws on the back, while the one that works only have the essentials. I have a feeling they are not the same type even tho they both are the REX-C100. But if this is the case, i find it really weird that it would make such a big difference.

EDIT: After checking the packaging for the controllers i see that one is ranged from 0-400c and the other one 0-999c. maybe this is the whole problem?
I ordererd the exact same controller in a quanity of 2 so they must have sent the wrong controller.

sounds really odd and there are no fixes per-se; the controller has some settings but I am not aware that anyone is setting more than the target temp.
here a little checklist :
1. make sure you’re testing the PID, relay and thermocouple as well power outlets (one from the relay, and one from the mains) which belong to one circuit only.
2. test the thermocouple by holding it in the hand or use a lighter to see the temperature goes up
3. the relay has a status light, it should be on. use a multi-meter to see that there is really power coming out (typically terminal 2.)
4. it’s a good idea to go with babysteps and test only one heatband, in case of doubt, try another heatband

sorry for being a little generic but I’ve seen a few people who found the problem with the steps above and as said, try another relay, PID or heatband to exclude faulty units (can happen).

let us know how it goes, seems like a nice troubleshooting case for the wiki.
thanks in advance,

Hi, I have this problem with my band heaters heating up too fast. If is set the wanted value to 210c it goes up 600c because the relay let go too slow. Is there an easy fix for this problem?

@dirkvanvroeger made a cool topic about auto reversing a shredder

Hey there, we added a video about wiring a 3 phase motor to single phase using a VFD/Inverter as well adding an emergency and direction switch. Next: adding auto-reverse functionality via Arduino.  The pretty long video is for beginners and you can apply it to the shredder and extrusion machine.

@danielmendez, looks alright, just make sure : inner diameter fits on your barrel, and : height is big as possible. If possible put as many heatbands as you can on it 🙂

Hi there,
we’ve seen many questions outside of the forum and also our users needed something more detailed. Here is a short video to understand the essentials of the circuit.

Hello everyone,
Can you make  video demo which shows how to setup complete Electronic Schematics for compression machine?am stuck,please help


Cheers Jerzeek

Had me stumped with these heater bands as there are no markings on them and trying to get this connected so i can test the PID’s but will have to wait for a test run due to my coupler not turning up.

And work has a lathe but no cutting tools to make one to suit my screw and gear drive.

You are right about the earth wiring
The polarity of the live and neutral doens’t matter,

Do you know what type of thermocouple you used? a K-type?

Hello @jerzeek I just set up my compression machine and everything looks fine except for the PID controller. When I test the PID Controller and set the SV to 40°C, the PV shows a temperature measurement beyond the value set in SV. The SSR, stops from blinking when it reached 40°C and the heater also stops from producing more heat. However, the PV in PID controller didn’t stop from the set SV value… instead it should stop from 40°C … it reach 54°C and continued to increase…do you know the reason for this and how can I fix it?? Your response will be very appreciated. Thank you!!

*If someone knows the answer you may leave your reply also. Thank you guys!

Thank you very much for your response! @cgoflyn

@4al15me029 yes, but it requires some extra electronic. there are a couple of options. to me the best is a good inverter which gives you some status signal and an arduino to control the inverter, not much of a brainer. you can also place a sensor and complete the rest with an arduino as well. in a few weeks we publish an update for the v3 shredder. i will message you when it’s done 🙂