Finding a contact manufacture - Page 1
Forum section: electronics / projects

author: orion242
author_rank: Unknown
timestamp: November 10, 2014, 03:03:02 am
content: So I have a little test board for a HVAC controller that I peddle part time. It’s nothing special or exciting really, just a quick and easy way to test out the I/O on the controller or testing the programming without having to wire up sensors. Up until now I hand assemble them 5 or 10 at a time and never really thought I would sell more than a handful. Now I have inquires about supplying possibly 50 or 100 of them. Making that many by hand is not an option and I’m wonder at what point does a contract manufacture make sense?Currently I take single pins from board stacking jumpers and use them to connect the PCB to the controller terminals. This is pretty tedious to assemble and I assume is going to cost a small fortune to have a CM assemble. Spacing on the screw terminals is 10mm and there are a total of 32, though I only really need 25 of the connections.So my question is twofold. Will CMs do runs of 50-100 units and does anyone know of a more elegant solution for connecting PCB to screw terminals for a board like this (green PCB)?

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: November 10, 2014, 07:02:13 am
content: Instead of wires you can use longer screws that go straight into terminals through large through holes in a board that covers all terminals, but that is same amount of "screwing"You can do that with 4 or 6 screws only and fill the rest with spring loaded test terminals (http://www.ebay.com/itm/100-Pieces-P75-J1-Dia-1-02mm-100g-Spring-Test-Probe-Pogo-Pin/231266490861?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D27538%26meid%3D1d716e874c4f4d6fb5db83d444afca82%26pid%3D100005%26prg%3D11353%26rk%3D2%26rkt%3D6%26sd%3D231043482292&rt=nc).I assume you doing it only for duration of test?

author: orion242
author_rank: Unknown
timestamp: November 10, 2014, 02:13:20 pm
content: Thinking about it more, it may be easiest to route the board edge with contacts that can slip in the screw terminals and use the PCB itself to make the required contacts. Completely removes the need for any extra parts or hassle.

author: robrenz
author_rank: Super Contributor
timestamp: November 10, 2014, 02:38:09 pm
content: If you don't want to take all the screws out completely to install it. You will need extra long slots and ears on the first inserted pcb edge to allow room to get the other pcb edge past and then under second side screw caps and yet still contact on the first inserted edge when slid back under the second edge screws. It would make for much faster insertion of the device.

author: calexanian
author_rank: Super Contributor
timestamp: November 10, 2014, 11:10:45 pm
content: If you just need somebody to stuff the boards domestically I recommend Telirite Technical Services.http://www.telirite.com//url] http://www.telirite.com//url]They are in Freemont and easy to work with in small quantities. If you want somebody to turn key it you are going to need some larger quantities. I would start by contacting EW Electronics in Chatsworth CA. They are part parts vendor and turnkey supplier. They will combine quantities with other parts for other customers and get things in asia cheaper and you don't have to deal with any of the import garbage or working directly with asia. They will also do you DFM and repackage the product if you need to make it easier to produce and more reliable. Talk to Rich. He is the owner and handles the turn key stuff. http://www.ewelectronics.com//url] Also if you have it made in China they can help you with the U.L. listing you are going to want if you do any serious quantity.

author: orion242
author_rank: Unknown
timestamp: November 11, 2014, 01:03:10 am
content: Quote from: Alexei.Polkhanov on November 10, 2014, 07:02:13 amThe controllers that this tests are removable from what you see in the picture. There are two D sub connectors at the top that the "brains" of the controller connects to. What is shown is just the back plate that all the field I/O wiring would attach to. Most of these test setups would be at a shop somewhere and dedicated to testing the controller electronics rather than installed in the field to test one. So you get the suspect electronics from the field, stick it on the base plate with the test rig and verify everything is working. The other use case would be someone developing the software for them and would have a dedicated demo board for the hardware.

author: orion242
author_rank: Unknown
timestamp: November 11, 2014, 01:04:34 am
content: Quote from: calexanian on November 10, 2014, 11:10:45 pmI just want the boards assembled, and sent back in bulk. I can package and distribute easy enough.Thanks for the leads!

author: calexanian
author_rank: Super Contributor
timestamp: November 11, 2014, 04:25:39 am
content: Then I would start with Telirite. Is it through hole or surface mount? as with any board house you will need to provide parts on spools with at least 6 inches of leader tape, or 6 inches of parts you don't mind burning. I take advantage of the digi reel from digikey. For things like I.C.'s I only buy in kit qty plus a couple extra they will re spool them for 7 dollars and put the leader tape on so they can feed them easily. For passives they are so cheap just buy full 3K spools. i think 0805 resistors are about $12 a 3K reel from digikey right now for standard parts. They typically have either a 1,2, or longer turn quote matrix they send you. We typically get 2 week and they are typically on time. They have both lead and lead free runs and do either no clean or water soluble. We use leaded, no clean. Boards look really good. They also pack and ship great. The really good crispy anti static bags.

author: orion242
author_rank: Unknown
timestamp: November 11, 2014, 04:28:13 am
content: Assuming I redo the board to make the connections to the screw terminals with PCB, everything is surface mount.

author: calexanian
author_rank: Super Contributor
timestamp: November 11, 2014, 04:37:31 am
content: They are very good with secondary through hole and back fill operations. Just give them a sample or a picture of how you want it. They can program the pick and place right off of your BOM provided the numbers make sence and they will get the stencil made for you. a good stencil depending on size will run you $250 to $300. Figure $500 or so in NRE fees total for programming and stencil for a small board. Also the PCB's will have to be laid out with a frame around it. Typically a scored edge of .25 inch is sufficient. If it is a small board you should panelize or array them.

author: orion242
author_rank: Unknown
timestamp: November 11, 2014, 05:17:44 am
content: Sounds reasonable. Thanks again.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: November 11, 2014, 08:15:12 pm
content: Quote from: orion242 on November 11, 2014, 01:03:10 amThen I would implement it in sort of classical way - place the board (DUT) to the bottom and test board loaded with spring-loaded contacts goes from the top attached to a frame with door hinges. You close it down, power up, run your test. Should be able to do whole thing in less than 20-30 seconds. I would even make the "start" button embedded in frame so it starts as soon as you close it.