The Brauduino (Matho’s Controller) Build/Advice/Question Thread

[blotto]

Wow, that sux! Does your pump cabling have any holes in it? It might have been wedged onto the mega's pins and shorted, could have been coincidence and just shorted while you were unplugging the temp probe? It certainly looks like a 240V short to me.

 

[Jase]

Wow, that sux! Does your pump cabling have any holes in it? It might have been wedged onto the mega's pins and shorted, could have been coincidence and just shorted while you were unplugging the temp probe? It certainly looks like a 240V short to me.

Blotto,

I think you're right. I can see a hole in the pump wiring. I'll replace the wire and order a new board. General consensus: order a genuine board from Arduino and steer clear of the eBay ones?

Cheers,
Jase

 

[blotto]

Yeah good question, I've had a few after market Uno's that have had their sockets fall off but when they are that cheap how can you go wrong? Jaycar has something resembling a mega not sure if it's suitable or not? https://www.jaycar.com.au/duinotech-mega/p/XC4420 might be faster than ordering one if you have a Jaycar close to home.

 

[Jase]

I have a Jaycar near work. I can order one from Arduino but I'm not sure what their delivery leadtime is like.

 

[blotto]

Yeah that's what I was thinking, not sure on delivery times from them. Maybe hit up Jaycar to see if it would be a suitable replacement? You might know but I'd have to ask as I know bugger all about these things. Lucky I can follow instructions

 

[zwitter]

Hi Jase
Did you run through ALL the setup section?
This is mandatory!
A common problem is not choosing electric for the heat. It defaults to gas in 2.8.3
Your photo shows that the temp connection has the resistor in the wires. This was something I introduced to stop the problems when plugging and un plugging the temp while the unit was powered on. Before that any time you plugged or unplugged the temp you would blow up the temp sensor. The resistor has saved countless temp sensors.

When you said went bang, exactly what sort of bang and from where?

James
Zwitter


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[blotto]

This was something I introduced to stop the problems when plugging and un plugging the temp while the unit was powered on. Before that any time you plugged or unplugged the temp you would blow up the temp sensor. The resistor has saved countless temp sensors.

James
Zwitter

Great work! I unplug my temp probe all the time due to having one in my HX and one in the kettle, that could have been a pain.

 

[Jase]

Hi Jase
Did you run through ALL the setup section?
This is mandatory!
A common problem is not choosing electric for the heat. It defaults to gas in 2.8.3
Your photo shows that the temp connection has the resistor in the wires. This was something I introduced to stop the problems when plugging and un plugging the temp while the unit was powered on. Before that any time you plugged or unplugged the temp you would blow up the temp sensor. The resistor has saved countless temp sensors.

When you said went bang, exactly what sort of bang and from where?

James
Zwitter


Sent from my iPad using Tapatalk HD

Hi James,

Thanks for the reply.

I had run through all of the setup sections after watching the youtube video on it a few weeks ago.

The bang was from the board, blotto was correct, the pump cable had been piercing by a pin. The pump cable was quite rigid. I'll grab some flex cable this week and will do a neater job of the wiring.

I'm frustrated with myself, I should have known better.

Just need to work out whether to order a replacement board from Arduino or try the Jaycar board that blotto suggested.


Cheers,
Jase

 

[bigmacthepunker]

Hey bigmacthepunker
In your setup is heat mode gas or electric?

James
Zwitter


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Hi James, yep on electric.

 

[Jase]

Sorry if you are reading this for a second time I added it to the wrong post:

Grabbed a UNO board from Jaycar. Updated the firmware and am back on track. Sorted. Thanks for everyone's help.

Just one thing that is amiss. The heat led is not working and on reflection I don't think it has ever worked. If you look at the led close up you can see a faint light. I thought it may have been the led itself but I swapped the colours and the red led works well in Pump led socket.

Any suggestions on how to fix the issue?

Cheers,
Jase

 

[barneey]

Hi Guys,

I'm in need of some advice please, a little while ago the unit developed a fault on the temp sensor, that I thought had been solved with a replacement lead however the unit now just reads 0.00c much the same as if a sensor wasnt connected, before that it was either 0 or 85c.

Anyway I thought I would take another look at the problem today & the unit wont switch on. I have tested the 12v power supply which is working + tried an independent power supply to make sure, still nothing. I thought I would plug in a USB power supply and the unit lights up but with a constant green LED on.

Any ideas what could have gone wrong?

Cheers

 

[zwitter]

Hi Barneey

Has the unit been completed and used in a system successfully?
Is this one of the most recent units as sold by Lael?
Is it permanently fitted to the system?

I ask just to get current status and a context for problems.

I assume that you have it apart to plug the USB power in?
When you say lights up but with green led on, does the display initialise and the program run?

The unit will not work completely with USB power as it only powers the board not all the other parts of shield etc.

Do you plug and unplug the temp probe at all?

What is your electronics knowledge and test equipment available?
Where are you located?

James
Zwitter



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[barneey]

Yep done quite a few successful brews with the fully built system, in a permanent setup, it was one of the 1st units sold by Lael. The probe is normally left in / had been left in since I finished the build. Things started to go wrong when the temp probe flicked between 0 & then got stuck on 85c during a brew.

With the supplied power supply / alternative supply = no led lights or display.

With a USB = display + able to change setting etc + a permanently on green LED, was flickering and now permanently on.

Test equipment would only be a multimeter, electronic knowledge more meccano than full on, soldering skill etc = OK

So would there would appear to be a power fault on the PCB? - what tests are needed / how to trace the fault line.

Location UK.

Many Thanks

 

[barneey]

Oh and the buzzer stopped working long ago.

 

[malt junkie]

Sounds like one of a few posible issues with the supply circuit. Easiest would be missing jumpers. Some pictures would help.

 

[zwitter]

Hi Barneey

Ok that sets the scene nicely. What connector is on the temp probe connection? The round multi pin one? Is the wiring all neat with no exposed bare wire that could short out anywhere?

One of the changes I made to the later version was to put a resistor in the positive power connection of the temp connection to the socket. As the mini stereo connection would otherwise short the connections and blow the temp probe. The older ones did not have this safety feature.

The buzzer and some of the other outputs rely on switching 12v to control the real world interface. USB only powers the arduino and some 5v powered bits.

There are 3 transistors that do this 12v switching and they can go pop. They were all the same but there were at least 2 different ones we used. I think this version was 2n2222a

Are you using a 240v pump?

Is the relay 5v or 12v version? There was a jumper for this on the PCB

To do testing without killing anyone it is best to remove the 240 from the PCB and make sure that the SSR connections and any other 240v connections are well insulated or disconnected.

I will put together a series of fault finding steps. I will refer to the 2013 early Lael kit in this instance but it is similar for all.

To prepare for the testing, set the board up where you can access the pcb, NO 240v connected. Probably fun a longer cable to the 12v supply to make moving PCB a little easier.

Start by measuring the 12v supply at the screw heads of the plug where the 12v plugs in to the shield PCB ?=
The 12v is just a direct feed from the external supply.

Then measure the 5v on the arduino pin or the 5v jumper near the relay or pin 2 of the LCD ?=
The 5v is "derived" from the 12v supply by a circuit on the Arduino assy. (Or direct from the USB supply if you connect that) never connect both USB and 12v supply.

I will post the next steps tonight. Pump, heat and buzzer.

Probably an idea to have a couple of spare resistors and bit of wire handy if you have them, maybe some spares like transistors but dont buy them yet.


James
Zwitter

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[barneey]

The lead on the temp probe is a stereo jack plug I have as a matter of course renewed the this plug + replaced the socket and wire with a spare on I had from the original kit, this has a resistor on the Red wire, now I understand why that was in place (so have at least learn something else today )

I will look and see what transistors I have on the board, assuming they are marked, can these be tested in situ -or need to be taken off, my multimeter does have a PNP / NPN test socket on it, but it might be worth just replacing?

I will carry out the test as mentioned later day (time difference 9hrs)

 

[barneey]

& if it helps the board version is 1.0

 

[barneey]

The tranys appear to have the marking p2n2 222a 617 on them

 

[malt junkie]

Before checking the PNP's I'd check there is current at the screw terminals power in(with psu attached not usb), then the 7805 (the yellow box behind the onboard relay) input(12v) and output(5v), also that all the jumpers are correctly placed (check the pics posted by jase over the last 2 pages).

Cheers
Mike