Choosing flexible Cables for lab use (power and logic) - Page 1
Forum section: electronics / beginners

author: nour
author_rank: Frequent Contributor
timestamp: October 30, 2016, 07:50:13 pm
content: I want to make My own custom length signal and power cables and I want the cables to be as flexible as possible.Also I want the cables to handle up to 10-20 Amps for the power cables(The cables used to connect you PSU and other devices and circuits) so the core will be around 1-1.5 mm in diameter and for the signal cables(logic level signals) I will not need more than 0.25mm diameter.My question is what is the isolating material that I should choose and what is the specifications that I need to care about in the wire (the cable core).I want the cable to be flexible and has a good binding radius like any good DMM or Oscilloscope cablesI have tried PVC but it is very stiff, also tried silicone but the performance wasn't as I expected!!

author: cowana
author_rank: Frequent Contributor
timestamp: October 30, 2016, 08:01:33 pm
content: What was wrong with silicone? High strand count wires with a silicone jacket are likely to be the most flexible you can find - the only real issue with silicone for everyday lab-use is some of the softer compounds can get nicked/cut very easily.Hirschmann do an excellent set of 60v/16A 4mm test leads (in all colours), which are handy item to have around.http://www.farnell.com/datasheets/1782406.pdf

author: nour
author_rank: Frequent Contributor
timestamp: October 30, 2016, 08:29:08 pm
content: After trying silicone I came to conclusion that it is not only the isolation material that matter!!I think there is something else also need to be taken care of about the core wires like for example the copper in the core must not be solid and it should be stranded, may be also it should be fine strings of wire to make it more flexible.That is just a guess not a 100% sure about it

author: nour
author_rank: Frequent Contributor
timestamp: October 30, 2016, 08:36:46 pm
content: I was searching around about this issue and found something called flexibility class and class 6 in the standard is the most flexible level, but I am not sure if this is what I am looking for or not(it seems to be the it)Can someone confirm this!

author: nour
author_rank: Frequent Contributor
timestamp: October 30, 2016, 08:48:23 pm
content: I am thinking about getting something like this and strip it and use its internal core wires for test leads and other stuff, it is very flexible and the wires are strandedhttp://www.tme.eu/en/Document/e81845f4f74e65a5edc657dc7ae7a8a3/B%20018%20LifYCY.pdf

author: cowana
author_rank: Frequent Contributor
timestamp: October 30, 2016, 10:40:41 pm
content: What makes wire flexible is a combination of the jacket material, and the internal core using a very high number of extremely thin strands.As an example, the test leads I linked to each have 259 strands of 0.07mm copper wire in them; the cable you linked to uses 102 strands of 0.05mm copper wire.

author: nour
author_rank: Frequent Contributor
timestamp: October 30, 2016, 10:46:06 pm
content: Quote from: cowana on October 30, 2016, 10:40:41 pmThat's a very valuable information I will make sure to use it when choosing the cablesthanks

author: nuno
author_rank: Frequent Contributor
timestamp: October 31, 2016, 12:55:38 am
content: Silicone jacket wire sold by HobbyKing is very flexible, and possibly cheaper than anywhere else.https://hobbyking.com/en_us/hardware-accessories-1/wires-connectors/silicon-wire.html(they have a few warehouses around world)

author: Dave
author_rank: Super Contributor
timestamp: October 31, 2016, 01:55:26 am
content: I bought most of the silicone cable that I use for test leads and such from Component Shop in the UK. Good quality insulation, high strand count, great solderability. The only thing that bothers me about those is that the jackets have "silicon" printed onto them.

author: BradC
author_rank: Super Contributor
timestamp: October 31, 2016, 06:16:33 am
content: Working through this particular issue myself at the moment, I'll just say that if you are looking at currents in the order of that which you mentioned, you are going to be dealing with fairly significant voltage drop issues on 1mm2 cables, so think carefully about what you are using them for before sizing your copper.I'm looking at making some 2.5 & 4mm cables for the higher current stuff because of the volt drop.Just something to think about.