Switch wiring id driving me nuts - Page 1
Forum section: electronics / beginners

author: AngraMelo
author_rank: Regular Contributor
timestamp: November 27, 2018, 01:31:06 am
content: Hello guys, I have the attached schematic and I´m about to wire the switch. What I have is a 12 position selector switch. It has a common pin that is then connected to the other 12 pins (one at a time) as you rotate it.I have no idea how to wire it by following the schematic. I dont know if I need 2 switchs or if I need to brigde the contacts.Can someone please help me?

author: piguy101
author_rank: Regular Contributor
timestamp: November 27, 2018, 01:59:34 am
content: It looks like to me that the switch is a double pole, five throw switch (DP5T). Is it something like this? 1825080-4 from TEhttps://www.digikey.com/products/en?keywords=450-2422-NDOr is it more like a rotary switch, or something else?

author: AngraMelo
author_rank: Regular Contributor
timestamp: November 27, 2018, 02:06:59 am
content: Hello friend,it is a rotary switch. here is the video of the guy making this project

author: rstofer
author_rank: Super Contributor
timestamp: November 27, 2018, 03:31:39 am
content: Like this:https://www.digikey.com/product-detail/en/c-k/A20503RNZQK/CKN10620-ND/3752049

author: Brumby
author_rank: Unknown
timestamp: November 27, 2018, 03:32:16 am
content: It's a double pole 5 position switch. Each bank has 5 positions and they are labelled SW1-A and SW1-B - which is interpreted asSwitch 1, bank AandSwitch 1, bank B. Each bank is electrically isolated from each other, but are operated together through a common mechanical movement.You can have it in a linear arrangement or rotary. Rotary is the most common in my experience.There are many ways to build a rotary switch - so I'm not going to try to describe more than just this one style....A common style is a single wafer with 12 contacts spaced at 30º around the perimeter. Inside this ring, there are (typically) 1, 2, 3 or 4 other contacts. All these are fixed in relation to the body of the switch. Mounted to the shaft is a switching plate that will have 1, 2, 3 or 4 pairs of wipers.You can get them with PCB pin or eyelet terminations:The configurations possible are, respectively, 1 pole, 12 position; 2 pole, 6 position; 3 pole, 4 position and 4 pole, 3 position. This is the general construction - you buy your switch in one of those configurations.There is usually a mechanical stop at each end of the rotation movement so you know when you've reached the first and the last position - but you can also buy a switch that has these mechanical stops placed differently. This means what looks like a 2 pole 6 position switch can have a stop after the 5th position - so it pays to check how many positions a switch actually has before soldering it in.Edit: Spelling

author: AngraMelo
author_rank: Regular Contributor
timestamp: November 27, 2018, 05:09:31 am
content: Thank you so much!!!!

author: Ian.M
author_rank: Super Contributor
timestamp: November 27, 2018, 06:12:44 am
content: You could also use two switches, one four way single pole rotary for the range selection at the SW1-B position in your circuit, and the other a SPDT toggle switch for the Test/Discharge switch at postion SW1-A. Be careful of the voltage rating of the toggle switch - there aren't many that can safely handle 400V DC

author: TERRA Operative
author_rank: Super Contributor
timestamp: November 27, 2018, 10:37:12 am
content: Those switches that Brumby pictured can often have their end stop adjusted.ie. for a 2 pole switch, each pole is shown as having 6 positions. By removing and rotating the metal ring seen at the base of the threaded portion to the appropriate position, you can limit the switch to 5, 4, 3 or 2 positions etc.

author: AngraMelo
author_rank: Regular Contributor
timestamp: November 27, 2018, 01:26:10 pm
content: Thank you guys for the helpI could use another separate DPDT switch but that means one more step during testing and as much as I wanted to use the rotary that I had (1pole 12 positions) it seems that Im going to order the correct 2 poles 5 positions.I finally understand the schematic, thank you again for your help!

author: spec
author_rank: Frequent Contributor
timestamp: November 27, 2018, 06:51:01 pm
content: What a great thread- just help and information all the way.