Contents
What is the resistance of a solder joint?
A resistance ratio of less than 1.00 shows the solder joint has a lower electrical resistance than an equal length of solid copper conductor; similarly, a resistance ratio greater than 1.00 indi- cates a higher electrical resistance in the soldered joint than in an equal length of solid copper.
What is the standard banana plug size?
4mm
Banana Plugs are referred to as a male connector and commonly found in either 4mm (standard) or 2mm (miniature) pin plug sizes. Banana plugs are designed to connect into Banana Sockets (Jacks) which again are available in either 4mm (standard) or 2mm (miniature) socket sizes.
Do wire connectors add resistance?
One thing that comes with every connector is additional resistance in our signal chain. The resistance, depending on the connector, can be a good or bad thing for what we are trying to achieve. Wires between items are much like traces and add another source or resistance.
Does solder add resistance?
The copper-on-copper connection is generally superior to solder considering that most solders have more resistance than copper. In practice, the difference in resistance between either methods (properly done) is beyond the accuracy range of average multimeters.
What is the unit of contact resistance?
ohms
The units of contact resistance are typically therefore in Ω. cm2 where Ω stands for ohms. When the current is a linear function of the voltage, the device is said to have ohmic contacts.
What is the resistance of a connector?
The overall resistance of a connector is often in the tens of milliohms. We must remember that constriction resistance is just part of the measured value, overall resistance, and for a majority of contacts, the initial constriction resistance is on the order of a milliohm or less.
Why are banana plugs good for contact resistance?
This is because they do not get contaminated like base metals. However, connecting banana plugs ‘wipes’ the contact surfaces, so even with base metals, a fresh connection will be good.
How much resistance is in a solder joint?
In PCB design the solder layer is very thin so the resistance is not a factor. But for joining wires it is a big factor. The second problem is that solder embrittles the soft stranded copper and makes it prone to fatigue stress breaks in high vibration.
Is the solder joint the weak link in a power supply?
As for the solder joint, there is no mechanical “contact” there, and the problems associated with it. It’s just a solid metal connection. Most likely the weak link is the copper trace on the board after the solder joint. For starters, analyze a solder joint as if only the copper were present, but directly connected.
What should the resistance of a banana jack be?
10 mΩ for a full-size banana jack sounds really high to me. However, the obvious things for you to do are: Measure it. Put a known current thru the connection and measure the voltage across it. This will tell you what you are actually getting, not the worst case it could be. Look at a datasheet.