Explain contact resistance, Electrical Engineering

Assignment Help:

Explain Contact resistance.

Contact resistance: It is measured as the voltage drop from tail to tail of the mated contacts along with specified current flowing through the contact and is given in milliohms. The total resistance offered through a contact depends on the bulk resistivity of the contact material, actual surface area and mechanical wear of the contacts and environmental effects. To acquire low contact resistance this is essential that the contact must be a fine conductor of electricity. The contacts must have good mechanical resistance against wear due number of mechanical operations. The contacts are made by using alloys that have combination of mechanical properties, very fine electrical and thermal conductivity and resistance to corrosion. Usually used alloys are Beryllium copper, spring brass, low leaded brass and phosphor bronze. Plating of the contact metal is completed to prevent deterioration of contacts chemically and mechanically and to acquire good surface conductivity. Commonly utilized plating materials are as silver, copper, gold, tin (Pb) and nickel.


Related Discussions:- Explain contact resistance

Evaluate the current flowing in the direction from b to a, Q A beam contain...

Q A beam containing two types of charged particles is moving from A to B. Particles of type I with charge +3q, and those of type II with charge -2q (where -q is the charge of an el

Compute the average number of open links, A zipper has N links every link h...

A zipper has N links every link has a state in which it is closed with energy 0 and a state in which it is open with energy 0 We require that the zipper only unzip from one side (s

Equivalent circuit of a dc machine, Equivalent Circuit of a DC Machine ...

Equivalent Circuit of a DC Machine A review of the material presented with regard to elementary direct-current machines can be helpful at this stage to recall the principles of

Dual-ramp analog to digital converter, Q. Dual-ramp analog to digital conve...

Q. Dual-ramp analog to digital converter? Figure (a) shows the block diagram of a dual-ramp (dual-slope) A/D converter. After a start-of-conversion pulse, the counter is cleare

How speech is transmitted in digital switching environment, Q. How speech i...

Q. How speech is transmitted in digital switching environment by using PCM/TDM? Ans: A digital carrier system is a communications system which uses digital pulses instead of

Determine about the wireless technology, Determine about the Wireless techn...

Determine about the Wireless technology Wireless technology (WiFi) enables connection of a computer to Internet without the need for connecting cables. A router (comprising a m

Process , Process The rectangle symbol  is used to represent  the pro...

Process The rectangle symbol  is used to represent  the process  operations as shown below.   MOV A, B

Cpi compare immediate instruction , CPI Compare Immediate Instruction ...

CPI Compare Immediate Instruction The 8 bit  data  specified  in the  instruction is  compared with the  contents of the accumulator. The comparison  is done by  subtracting

Explain crystal oscillator, Q. Explain Crystal Oscillator The frequency...

Q. Explain Crystal Oscillator The frequency of a crystal-controlled oscillator is held constant to a high degree of accuracy by the use of a quartz crystal. The frequency depen

Effect of supply voltage - stepper motor , Effect of Supply  Voltage ...

Effect of Supply  Voltage a.As the applied  as voltage  is increased hysteresis loss increases. b.Eddy current losses are given by W e α f 2 t 2 B 2 m Where B m =

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd