[Falcon69]

Also psykhon,

the A3144 works just fine. You can get those on Ebay. I don't see why those sellers won't ship to where you are. They are cheaper than the SS441 also.

Romanlini,
I already found a place to make the circuit boards. Pad2Pad.

I was talking about having the mounts made. I've explored the possibility of having them casted with resin. A local plastic supplier here told me that it wouldn't work. The resin would be too brittle. I've explored the possibility of having them injected molded, but that would cost too much. So, I need to explore the possibility of finding someone with a CNC to make the mounts, or I need to wait until I get my CNC done, which will be awhile on my Student Budget.

[psykhon]

Dont know about A3144, in datasheet, the a3142 seems to have a very stable operate and release points over an "ambient" temperature range (>-25º,<50º) but no such information is provided for 3144 and from the seccond table on page 3, magnetic charateristics, it doesnt seem any better than the SS549.
If anybody knows better, please let us know.

[RomanLini]

Psykhon- If ordering is going to be difficult anyway, I would just order the SS441. It can't be that hard to find, and it does have the "temperature compensated" feature so it's known to be very accurate.

Falcon69, sorry I did not realise you don't have a machine to make the mounts! If you check the early photos in the thread on my machine I just soldered the SS441s on tiny PCBs, and glued the PCBs to my machine on little slivers of plastic (to lift them to the right height) and the glue was silicone which is inert and will never fail.

As rough as it looks they have performed flawlessly that way since the day I made them.

You could do something similar with your little PCBs, to get your machine up and running, then make some better mounts as one of those great "first projects".

[Falcon69]

ya, i know. I like to do things the hardway. LOL

Ya know, I can have those pieces injected molded for about 30 cents each, but, I have to order 10,000 of each. :/

[bluejets]

Do not know if it has been covered before, 60 odd pages is quite a bit of reading, however, in the first postings, I see a pic of a hall switch.

Many instances it is a good idea to fit a bypass capacitor (100nf) right at the base of the hall effect across the supply. Eliminates any false triggering due to noise.

Also found that using optical switches (from old printers etc.) give a repeated accuracy less than 1 thou".

[Falcon69]

bluejets,

Looking at the drawing on post #725, where exactly and how would I put that capacitor? I'm glad you chimed in, because I'm going to have some of these boards made soon. And it seems those capacitors could be an improvement.

[john-100]

Hi

you just need to connect the capacitor across the SS411's
ground and +5V supply

you can see one in the picture in post 534

John

[Falcon69]

Thank You John. I kinda thought that was the way it went. thanks for confirming.

Question: The LED's draw 20ma each, not sure what the sensor draws, but can I get away with 1/8 watt resistors? Or should I stick with the 1/4 watt?

[john-100]

the 150 ohm resistor that limits the current to the red LED will disipate
the most power

if the volt drop across the red LED is 2V you will have 3V dropped across
the 150ohm resistor and the resistor will disipate 3V X 0.02A = 0.06W

in free air 1/8W will be OK
for the resistors that will be encapsulated in resin
I'd use the 1/4W resistors

the 100 ohm resistors limiting the green LED's current will only disipate 0.04W

John

[Falcon69]

okay, thanks John.

I can fit the 1/4 watt and the capacitor on the dual LED sensor switch, but on the single LED using the 3.5mm headphone jack for connectivity, there's insufficient room to fit the capacitor, without enlarging it, and if I do that, it won't fit in the cases that you have designed. I'm trying to keep everything small.

[john-100]

If you can't fit the capacitor in the sensor assembly

you may be able to wire a small axial capacitor like this one -

A104K15X7RF5TAA - VISHAY BC COMPONENTS - CAPACITOR, 0.1UF, 50V, X7R | Farnell United Kingdom

inside of the 3.5mm plug


John

[RomanLini]

(edit; Moderators have removed the 2 spam posts now!)
(I said) Post 752 appears to be a spam linking to an amazon page. Post 753 might also be a spam. Both reported.

[epineh]

Yeah there seems to be a run on spam at the moment, feel sorry for the mods of the forum, it would be a full time job getting rid of it all. Personally I find the "English" spammers use quite amusing, makes their posts so blatantly obvious to be a scam, lol.

Russell.

[racedirector]

Sorry to be a pain but I am still struggling a little with the wiring side. I cut out my mounts today so am ready to start assembly. On my new machine I will be using a MB-02V6 breakout board from Homann Designs, it is this I am confused about and the need for pullup resistors. (http://www.homanndesigns.com/store/i...products_id=59)

I would like to have an led on both the sensor mount itself and the main panel I am building and will be using these switches as homing AND limit switches at the same time. I am building a Joes 4x4 so have X, Y, Z & A axis to populate. I have almost every size resistor known to man.....alright not quite that many but I bought a stack for this project, enough to cover (hopefully) the requirements. If someone would be kind enought to help me out it would be appreciated.

Cheers
Bruce

[racedirector]

Hi John
So when I went to order second time round I just went too my previous order which weren't in stock , wish I would have known that they are basically the same , would have saved loads of 1300 numbers, never mind got them now , just cut out some new cases for switches & magnets,
Attachment 159357

Cheers
Riche.


Sent from my iPhone using Tapatalk

Hi Richie

Can I ask where you got the files for this array of mounts? I only have the switch one from around page 2 of the thread and am looking for others like in your image...

Cheers
Bruce

[phomann]

Sorry to be a pain but I am still struggling a little with the wiring side. I cut out my mounts today so am ready to start assembly. On my new machine I will be using a MB-02V6 breakout board from Homann Designs, it is this I am confused about and the need for pullup resistors. (MB-02-V6 Bidirectional Breakout Board [MB-02] - US$39.50 : Homann Designs!, The preferred CNC Component Supplier)

I would like to have an led on both the sensor mount itself and the main panel I am building and will be using these switches as homing AND limit switches at the same time. I am building a Joes 4x4 so have X, Y, Z & A axis to populate. I have almost every size resistor known to man.....alright not quite that many but I bought a stack for this project, enough to cover (hopefully) the requirements. If someone would be kind enought to help me out it would be appreciated.

Cheers
Bruce

Hi Bruce,

Pullup resistors are used on inputs to ensure that the input is in a known state when the input is not activated. Without a pullup, the input could "float" around and generate false triggers.

As the MB-02 BoB has pullups (4K7) you don't need to add additional ones.

As to the multiple LEDS, you can put two in parallel, but get the low current ones as the sensor has a maximum sink current of 20mA.

Hopefully the above is clear?

Cheers,

Peter

[racedirector]

Thanks Peter, still working my way through the MB-02. Will get these wired and tested in the next few days.

Cheers
Bruce

[Falcon69]

I'll be getting the circuit boards made up at the end of this month, so I expect delivery within the first couple of weeks of October.

It doesn't cost that much more to make a few extra boards.

I plan on making a few of the mainboards with an external USB connectors, connected via a 40pin cable. This way, the USB connectors can be connected to the back of a panel box for a cleaner install and routing of wires. This is for the dual Color LED switch boards with external LED mounts as well for mounting to the front of the control box to monitor the switches.

I will make a few of the Boards for the standard single LED indication switch with a 3.5mm headphone jack connection.

These switch boards will have the hall effect sensor, resistors, capacitors, etc. all mounted on them. The switch boards are able to fit into the mounts Romanlini designed earlier.

Is there anything else I should add to these boards, switch boards or mainboards, other than the capacitors for signal filter? (to help eliminate false triggers) I want to make sure I get these boards built right.....the first time.

I'm not sure on what the cost will be, yet. I have to figure out how much the electronics are costing me. I have to buy a reflow oven, soldering station, and of course, stencil kits, so that will determine cost as well.

I plan on only making maybe 100 mainborads with 7 of the switch boards per mainboard (700 total) and plan to make maybe 500 switch boards of the single LED, originally designed by Romanlini.

I do have one question... The A3144 hall switches that can be bought off eBay cheaply, do work. I've tried them on my proto board. However, the magnet to trigger them (3mmx8mm dia) must be closer than 1/8" - 1/4" depending on how they are mounted. Do the Honeywell SS441 work alittle better? I'm just trying to justify the cost. I can get 100 of the cheaper ones on eBay for $18.50 whereas it will cost me (from Mouser) $104.00 for 100. That's a big difference in cost.

It just doesn't make sense to make just one set for myself. It only costs a few more dollars to make a few more boards. SO, I should have some to sell, for those interested. I'll try and make a video of the switch boards and switches actually working.

I checked to see what it would cost to have the switch cases proffesionally made, using plastic injection....about $5200 for 4000 of them. So, I won't have any of those to sell. That's just too much to spend.

Anything else I should add to these boards? I've added the lamp test rocker switch, to test all the LED's and added the capacitors as mentioned before. I even added an extra output to control another LED for something else, with a jumper to select the voltage.

The mainboards are pretty small. Gotta love surface mount. About 50mm x 75mm. Thats including the screw terminals, 40pin external connector, and even the panel mount connectors for both colors of LED's.

[LazerBee]

Its not much difference but Jameco Electronics has them for $95.00/100. The part # is 1915886

[Al_The_Man]

SS441a at Digikey are just over a $ each.
Next day Delivery.
Al.