Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: The Energy and Mass of Ag/C and Cu in Protection d...

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: The Energy and Mass of Ag/C and Cu in Protection d...: The Energy and Mass of Ag/C and Cu in Protection devices The Ag/C step   contact material   shows the maximum electron energy  ...

The Energy and Mass of Ag/C and Cu in Protection devices

The Energy and Mass of Ag/C and Cu in Protection devices

The Ag/C step contact material shows the maximum electron energy less than the Cu Punch contact material. However, there is only one chemical element, O II appears in both Ag/C step and Cu Punch contact material. Both contact Material Ag/C step and Cu punch have the same lowest energy at the wavelength 821 nm for chemical elements N I, O I and O II.

The Mass of the chemical elements Ag I and Cu II is higher than other chemical elements about 4 times in the Ag/C step contact material. The maximum Mass when using the Cu Punch contact material is the chemical element Cu II at the wavelength 776 nm. This confirms that the chemical element Ag I and Cu II come from the contact material. Both the Ag/C step contact material  and Cu Punch contact material show the minimum Mass is the chemical element H. The average Mass of Ag/C contact material is 0.026g higher than Cu Punch contact material.

The highest temperature rise of Ag/C step contact material belongs to chemical element N III at the wavelength 500 nm. The maximum temperature rise for the Cu punch contact material is the chemical elements NII at the wavelength 428 nm.  The maximum temperature rise for the Cu punch contact material is higher than the Ag/C step contact material. Both Ag/C step contact material and Cu Punch contact material have the same minimum temperature rise and the same chemical element Cu II, at the wavelength 776 nm. The average temperature rise for the Ag/C contact material is lower than the Cu Punch contact material about 0.25x10^-33 K. 

Reference:  Arc Control in Circuit Breakers: Low Contact Velocity Paperback – January 1, 2017 by Dr Kesorn Pechrach PhD (Author)

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: Chemical Elements in Short Circuit Breakers

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: Chemical Elements in Short Circuit Breakers: Chemical Elements in Short Circuit Breakers The maximum energy when contact opening velocity at 10 m/s is higher than the contact ...

Chemical Elements in Short Circuit Breakers

Chemical Elements in Short Circuit Breakers

The maximum energy when contact opening velocity at 10 m/s is higher than the
contact opening velocity 1 m/s. However, they have the same minimum energy and
the same chemical element N I, O I and O II. The average energy when the contact
opening velocity 10 m/s is slightly higher than the contact opening velocity 1m/s.
Both contact opening velocity of 1 m/s and 10 m/s has the same minimum and
maximum Mass. The maximum Mass, when the contact opening velocity 10 and 1
m/s is the chemical element Ag I. The minimum Mass is the chemical element H. The
Mass average when the contact opening velocity 10 m/s is 0.003g higher than the
contact opening velocity 1 m/s.
The maximum temperature rise when the contact opening velocity 10 m/s, the
chemical element N II, is higher than the contact opening velocity 1m/s the chemical
element N V. The minimum temperature rise of the contact opening velocity 10 m/s,
is the chemical element Cu II, is not significantly different from the minimum
temperature rise of the contact opening velocity 1 m/s.

Reference:  Arc Control in Circuit Breakers: Low Contact Velocity Paperback – January 1, 2017 by Dr Kesorn Pechrach PhD (Author)

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: The Effect of Magnetic Forces on Arc Control

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: The Effect of Magnetic Forces on Arc Control:  The Effect of Magnetic Forces on arc control The magnetic forces on the arc root increase as the arc current increases. The contac...

The Effect of Magnetic Forces on Arc Control

 The Effect of Magnetic Forces on arc control

The magnetic forces on the arc root
increase as the arc current increases. The contact gap has a minimal influence on the
magnetic forces on the arc root. The magnetic forces on the arc root are mainly
dependent on arc current.

The different is the influence of the shapes of the
contacts are modelled. From the experimental results in Section 4.3.1, Chapter 4, the
Ag/C on the moving contact causes a longer delay in the tip of the moving contact.
An Ag/C step and Ag/C flat on the fixed contact are used to compute the magnetic
forces on the arc root, see Figure 3.19, Chapter 3.

The material of the arc runner is Cu and it is 1.0 mm thick. The material of the
contact is Ag/C (95/5 %) and 0.8 mm thick. The anode is on the moving contact and
the cathode is on the fixed contact.
A Silver/Graphite contact pad with a step to the surface of the arc runner is shown in
Figure 5.4. A Silver/Graphite contact pad flushes without a step to the surface of the
arc runner is shown in Figure 5.5.

Reference: Arc Control in Circuit Breakers: Low Contact Velocity Paperback – January 1, 2017 by Dr Kesorn Pechrach PhD (Author)

Variable factors in Arc Control

Variable factors

To investigate the influence of Ag/C contact
materials on the arc root motion from the contact
region, a piece of Ag/C is welded on the fixed and
the moving contact when the anode and cathode
power supply are set in the fixed and moving
contacts.
To inspect the influence of the short circuit current
level on the arc root commutation from the contact
region, three levels of the short circuit current are
expected: 500 A, 1400 A and 2000 A. The Capacitor
Discharge System (CDS) is charged up with
capacitor 47.4 mF, inductor 224 μH and resistance
30 mΩ [2].

Reference: 

Arc Control in Circuit Breakers: Low Contact Velocity