reef-pi :: An opensource reef tank controller based on Raspberry Pi.

Bigtrout

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Thanks, i'll pick up some lower value resistors on Monday and try again. The RJ45 connectors are quite conveniet and cheap in comparison to anything else, good quality DB connectors are expensive here, basic ones are cheap and just not nice at all.
If you want to test, 2 4.7k resistors in parallel equals 2.35k, but I would go too low on that value(stay 1.5k or greater)
 

stefanm

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I mean the physical wiring on your ethernet jacks and plugs. Double check that and start with getting one sensor working

Ok understood, I wired them mysef and tested continuity so should have been correct, I did triple check.
 
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Ranjib

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Is there a way how to use i2c temperature sensor instead of the dsb1802? I'm referring to ezo temperature module by Atlas.
Thanks
Not currently. I may add support for this, since we have introduced a new hardware layer that makes doing such things easier.
 
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Ranjib

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I decided to reinstal Raspbian and reef-pi 2.1, still not reading the temperature sensors, I have the sensors connected to around 8 ft of cat6 cable and an RJ45 socket and plug, I removed the cat6 wire and connected the sensors to the pi and it works!

Capture.PNG


So is cat6 cable not suitable for this type of project? If I recall correcty I think I had the same issue with the Arduino. Can I still use the cat6 if I use shorter lengths and where needed solder multi strand wire to the cat6?

Anyone care to comment?
i dont think so, i think its circuit issue (short or continuity )
 
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Ranjib

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One quickie regarding the doser part, can I add more than 2? and what would be the jack number or is it related to which GPIO I choose? @Ranjib
With Pi, you are limited to only two pwm channels, hence theres a limit on only two dosing pumps. With pca9685 , that will be increased to 16
 

stefanm

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With Pi, you are limited to only two pwm channels, hence theres a limit on only two dosing pumps. With pca9685 , that will be increased to 16

So if I want to run 4 dosers I need to use a pca9685 and software no issues, right?

I think I have a working spare so I can give it a try.
 

Bigtrout

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Now I know what keystones are, I think i need to get a proper punching tool, 99% sure that's the issue.

Thanks guys!
Yes a punching tool helps...but you can try seating the wires with a small flat screwdriver, like an eyeglass type. Rj45 plugs take stranded or solid but most rj45 jacks are made for solid wire, so very small stranded wire sometimes get cut and dont make good connections when punched into the jacks.
When i did my temp sensors my hat has 3 wire connectors, of course they are stranded, to punch them into the jacks, i stripped them and tinned the ends to be punched in so when punched down into the jacks the jack had something to "bite" into, then I tested continuity before trying them out.
 

stefanm

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Yes a punching tool helps...but you can try seating the wires with a small flat screwdriver, like an eyeglass type. Rj45 plugs take stranded or solid but most rj45 jacks are made for solid wire, so very small stranded wire sometimes get cut and dont make good connections when punched into the jacks.
When i did my temp sensors my hat has 3 wire connectors, of course they are stranded, to punch them into the jacks, i stripped them and tinned the ends to be punched in so when punched down into the jacks the jack had something to "bite" into, then I tested continuity before trying them out.

Thank you, I'll give that a try, last resort I'll try changing the resistance.
 

Bigtrout

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It’s amazing how many connector issues we experience . This probably the biggest pain point across all the threads. So simple but still so failure prone :-/
As a hobbiest its difficult and expensive to have the proper tools to do the more reliable connectors. For the jst-xh on my hat board, I ordered premade pigtails and solder and tape/heatshrink them to the pigtail of the other type connector I need. Not worth investing in an expensive crimp tool, and the cheaper crimp tools are a big crapshoot.
I use ethernet jacks because I have good tools to make them. In the end, I like good old screw terminals but size become an issue.
So yes, you are right, connectors can be a trouble spot, and the first place to look when something doesn't work as planned.
 

theatrus

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As a hobbiest its difficult and expensive to have the proper tools to do the more reliable connectors. For the jst-xh on my hat board, I ordered premade pigtails and solder and tape/heatshrink them to the pigtail of the other type connector I need. Not worth investing in an expensive crimp tool, and the cheaper crimp tools are a big crapshoot.
I use ethernet jacks because I have good tools to make them. In the end, I like good old screw terminals but size become an issue.
So yes, you are right, connectors can be a trouble spot, and the first place to look when something doesn't work as planned.

Proper crimp tools for some connectors are easily $500+ for the hand tool. It’s absurd.

You can do passable crimps using the Engineer pliers from Japan. Engineer PA-09 Micro Connector Crimpers https://www.amazon.com/dp/B002AVVO7K/
 

rushbattle

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It’s amazing how many connector issues we experience . This probably the biggest pain point across all the threads. So simple but still so failure prone :-/
Standardization is a big help in these sorts of issues, but that is counter to the open source methodology. @theatrus seems to be on the right track these days with connectors, and the big help is putting a bunch of stuff on one PCB, which removed the need for lots of wires and connectors everywhere.

I see reef-pi as having a three tiered level system. First tier is the Base Board and the like, all you have to do is a bit of screwing things together, and perhaps soldering the temp sensor will become unnecessary soon ;). Most everything else just plugs into the board as is, really easy for someone slightly familiar with linux and hardware in general.

Tier two is being able to follow guides, and build your own machines with custom capabilities. You have many more wiring and connector issues with this tier but it is great because it is cost effective and super flexible for a given set of needs/wants.

Tier three is, uh, @Ranjib @theatrus and a few others here that I won't name because I don't want to forget anyone! More or less, experts that have a broad and deep understanding of these types of systems and can help guide the Tier 2 folks with their projects and are generally the shepherds of the the whole concept.

I bring this up because it helps set expectations. Might help with folks understanding what it takes to get to tier two, and making the commitment to the time to understand a bit deeper rather just jumping in and winging it. (And then asking silly questions in the megathread like me!)
 

rushbattle

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As a hobbiest its difficult and expensive to have the proper tools to do the more reliable connectors. For the jst-xh on my hat board, I ordered premade pigtails and solder and tape/heatshrink them to the pigtail of the other type connector I need. Not worth investing in an expensive crimp tool, and the cheaper crimp tools are a big crapshoot.
I use ethernet jacks because I have good tools to make them. In the end, I like good old screw terminals but size become an issue.
So yes, you are right, connectors can be a trouble spot, and the first place to look when something doesn't work as planned.
Always check grounding first, right?! It's amazing how many times it's a grounding issue. Reference points are important, in all aspects of life :)
 

theatrus

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I’ve been buying various 1 wire probes to find a good source. Latest ones are a bit weird:

- the metal is actually stainless this time
- there is no visible potting seal at the cable entrance.

I need to whip out a power tool to cut these apart to see if there is potting deeper inside or not, as the metal is actually stainless now.

Always cut away the heatshrink on these - it’s not going to form a watertight seal anyway.

312defbeacf708985dbbce4767b4c9a8.jpg
 

Bigtrout

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I’ve been buying various 1 wire probes to find a good source. Latest ones are a bit weird:

- the metal is actually stainless this time
- there is no visible potting seal at the cable entrance.

I need to whip out a power tool to cut these apart to see if there is potting deeper inside or not, as the metal is actually stainless now.

Always cut away the heatshrink on these - it’s not going to form a watertight seal anyway.

312defbeacf708985dbbce4767b4c9a8.jpg
@theatrus
I bought 2 drok branded before Xmas that are fantastic. 12 dollars for 2 3m probes. Real high temp silicone insulation. Double crimped. Real Stainless, the wire was shielded. ALAS, they ran out and no more to be had. I work in industrial settimg and these are industrial quality!
The last one from Drok looks like the one in your picture...disappointing, but its going to be my ambient air temp sensor.
20190103_004315.jpg
 
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