Electric Information

Cable Tray and Wire way are commonly used in electrical wiring in industrial applications. There are advantages to easy installation, convenience, speed and can put a lot of calls. Well ventilated Can use both electrical systems Medium, high and low pressure Made of thin steel sheet Can coat many different types to suit each type of cable tray, including Aluzinc, Electrogalvanized, Hot dip galvanized, Epoxy powder paint and Galvanized sheet. Good rust prevention. The general purpose can be divided as follows

To install the Cable tray, appropriate joints and accessories are needed, as follows

Example of a Cable tray installation

Circuit Breaker

Is a device that operates on and off electrical circuits without automation. But can open the circuit automatically If the current flows more than the specified value By preventing the equipment connected to the circuit breaker to be damaged by excess current Divided into many types

Working principle of circuit breaker

The operation of the circuit breaker When the current in the circuit is overload that the circuit breaker can accept, the contact of the circuit breaker will open the circuit with the following working principle

Thermal Trip. This type of work has an internal structure consisting of 2 bimetal metal plates which are made of metal That have different types of heat coefficients. When the current flows through the metal, the metal will bend the metal to bend and release. A mechanical device causes the circuit breaker to call a trip.

Magnetic Trip. This type of operation relies on the working principle of magnetic field power. When the circuit causes short-circuit or over-current Will cause a high intensity magnetic field and then release the mechanical device Causing the circuit breaker to break or open the circuit Which works like this, will break the circuit faster than the model

Thermal Trip Thermal-Magnetic Trip When the current in the circuit exceeds the contact rating of the circuit breaker, it will open the circuit. By relying on both the heat And the induction of the magnetic field helps to release the contact mechanism to open the circuit

Solid State Trip or Electronic Trip. This type of working principle uses electronic circuits together with circuit breakers. The trip current can be adjusted to work in various districts. The internal structure has a current transformer (CT: Current Transformer) inside the circuit breaker, which converts the current down and the microprocessor to analyze the current. If the current exceeds the limit Will order the circuit to be disconnected

Types of circuit breakers

Miniature Circuit Breakers (MCBs) are small-sized breakers often used in buildings. Can be used as a protection device with a load center or consumer cabinet Consumer unit has a short-circuit current rating. Is a circuit breaker that cannot adjust the circuit breaker setting. And most rely on thermal and magnetic release mechanisms. For choosing an MCB for placing in a consumer unit, we can install this protection device in 2 points, which is the main or main circuit breaker and the sub-circuit which The main breaker point must select the current from all loads. In most cases, it is approximately 100 A for MCB. The current selected depends on the load at each point of use, such as lighting loads, receptacle loads, refrigeration loads, and water heater loads. Basically, things to consider before choosing are the number of poles, the values In, Icu, and various standards, etc. In which the rated current is the maximum operating current that the circuit breaker can tolerate under normal operating conditions and environments. Icu is the maximum short circuit current that the circuit breaker can withstand and Also can break the circuit without damage to the circuit breaker itself, usually shown in the form of kA RMS

Residual Current Devices (RCDs) Automatic breakers that cut off electricity within a specified period of time. When the electric current flowing in and out Not equal That is, there is some electricity that is lost, such as leakage from grounded appliances. Or electric current leak through people who come into contact with equipment that has leakage electricity During normal use, there will be no electric leakage, so the leakage circuit breaker will not work, most will be installed in the consumer cabinet. Residential units Circuit breaker There may be other names such as residual current circuit breakers (RCD, RCBO, RCCB) or ground leakage circuit breakers (ELCB, GFCI) being used in conjunction with other types of circuit breakers such as brakes. Small child MCB or circuit breaker There are 3 types of MCCBs, but they are widely used: RCCB (Residual Current Circuit Breakers), RCBO (Residual Current Circuit Breakers with Overload protection) and ELCB (Earth Leakage Circuit Breaker).

Molded Case Circuit Breakers (MCCB) is a breaker that is considered popular for use in industrial plants and large buildings. With features that can withstand short circuit currents or kA values ​​and support currents that are higher than the circuit breaker (MCB) but less than the circuit breakers ACB, the current size will range from tens to thousands of amps

Air Circuit Breakers (ACB) are circuit breakers that protect the main cable. Commonly used with high-voltage (HVAC) structures, generally made of steel, with large and strong arcing chambers in order to be able to receive a large number of short-circuits. Most work principles are by using electronic devices in Detection and analysis of current to order to disconnect the circuit

The minimum size of the ground wire that moves to the electrical equipment or receptacle is according to the size of the overcurrent protection device as in the following table.

International Protection Standard

This table shows the sequence and necessities that must be specified in order to be considered a complete IP standard.

IP symbol	Solid protection	Liquid protection	Impact resistance	Other protection
IP	Numbers 0-6	Numbers 0-9	Numbers 0-9	The character
Is required	Is required	Is required	Deactivated	No need to specify

This table shows the level of protection against solids. These solids are defined as to prevent access (into the device) of dust or accidental contact only, not including solid impact. The impact resistance is described in the 3rd digit of the IP standard and has now been discontinued. There are 7 levels of solid protection from 0-6 as follows

degree	illustration	Details
0		Without any protection
1		Protect against solids that are 50 mm or more For example, to prevent accidental contact with the device from hands or other parts of the body.
2		Protected against solids up to 12 mm in size For example, to prevent accidental contact with the device from fingers or other tools. Of similar size
3		Protect against solids that are 2.5 mm or more For example, to prevent accidental contact with the device from screwdrivers or other tools. Of similar size
4		Protects against solids from 1 mm or more For example, to prevent accidental contact with the device from wires, wires, small screwdrivers, some insects, or other tools. Of similar size
5		Dust can be prevented, but there may be a small amount of dust that has been leaked into the system. The dust that has entered must not have any effect on the operation of the equipment. For example, in most cases this IP standard is placed in portable meters or occasional devices, where dust can enter through the battery cover, but due to the short operating time, it is almost impossible to enter the dust. at all
6		Completely dustproof This standard was tested on areas with air and dust circulation for 8 hours. For example, in most cases this IP standard will be in the measuring equipment or other equipment that is used in the area all the time.

This table shows the level of protection against liquid, in which the liquid mentioned is only liquid, not other types of liquid such as oil, chemicals with high acidity or alkali etc. Levels from levels 0-9K as follows

degree	illustration	Details
0		Without any protection
1		Protect only water drops that fall vertically on the device. Test by releasing water droplets vertically equal to 1 mm / min rainfall for 10 minutes
2		Protects against drops of water falling in an oblique direction around the device at an angle of up to 15 degrees from the vertical. Tested by releasing water droplets in an amount equivalent to 3 mm / min rainfall for 2.5 minutes / side (10 minutes total). All 4 sides are tested on the left, right, front and back of the device.
3		Protects against water droplets that are slanted in an oblique direction around the device, at a maximum angle of 60 degrees. Test by using spray nozzles to spray the device with a protective sheet for water. (To obtain the test angle) at a pressure of 50-150 kPa and a flow rate of 10 I / min for 1 minute per 1 m2 of equipment space, with a total test time of at least 5 minutes.
4		Protection against spray That can hit the device in every direction. Test by Spray Nazzle spraying around the device at a pressure of 50-150 kPa and a flow rate of 10 I / min for 1 minute per 1 m2 of equipment space, with a total time of at least 5 tests. minute
5		Protects against water from injection in all directions. Tested using a 6.3 mm nozzle around the device at a pressure of 30 kPa at a distance of 3 m and a flow rate of 12.5 I / min for 1 minute per 1 m2 of equipment. Resort all at least 3 minutes.
6		Prevent water from severe injection On the device from all directions. Tested using a 12.5 mm nozzle, spraying around the device at a pressure of 100 kPa at a distance of 3 m and a flow rate of 100 I / min for 1 minute per 1 m2 of equipment space. At least 3 minutes
6K		Prevent water from high-pressure injection On the device from all directions. Tested using a 6.3 mm nozzle around the device at a pressure of 1,000 kPa at a distance of 3 m and a flow rate of 75 I / min for 1 minute per 1 m2 of equipment. At least 3 minutes
7		Prevent water infiltration By soaking with the device in the water that has a maximum depth of 1 m for a maximum of 30 minutes. In the case of a small device, the device is immersed in water with a depth of 1,000 mm, measured from the lowest point of the device to the surface. In the case of large devices, the device is immersed in water at a depth of 150 mm, measured from the highest point of the device to the water surface for a period of 30 minutes in both cases.
8		Prevent water infiltration From the permanent immersion of the device in the water Testing due to different working depth of each equipment Testing of this IP standard will depend on the manufacturer directly, which will specify the maximum depth of use of the device.
9K		Prevent water from ultra-high pressure injection On the device from all directions at a maximum water temperature of 80 ° C Test using the nozzle (Nazzle) to spray around the device in 4 positions, at an angle of 0, 30, 60, 90 degrees from the vertical of the device at a distance of 100-150 mm with a pressure of 8-10 MPa and a flow rate of 14- 16 I / min at water temperature 80 ° C for 30 seconds each position (total of 2 minutes)

* The standard with the symbol "K" is a standard established by ISO 20653, which is not in IEC 60529 except IPx9, which has the same test as IP69K.