Technical Specifications of various electrical lamp technologies

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Are you specifying electric lamps and you need information on the wattage and service life of the commonly used electrical lamps? Here we have listed the wattage, efficiency (lumen/watt) and service life (hours) of some commonly used electric lamps to aid in selecting the right lamps.

Lighting Technology	Power (Watt)	Efficiency (Lumen/watt)	Service Life (Hours)
Standard Incandescent	3 - 1,000	10 - 15	1,000 - 2,000
Halogen Incandescent	5 - 500	15 - 25	2,000 - 4,000
Fluorescent tube	4 - 56	50 - 100	7,500 - 24,000
Compact fluorescent lamp	5 - 40	50 - 80	10,000 - 20,000
HP Mercury Vapor	40 - 1,000	25 - 55	16,000 - 24,000
High-Pressure Sodium	35 - 1,000	40 - 140	16,000 - 24,000
Low-Pressure Sodium	35 - 180	100 - 185	14,000 - 18,000
Metal halide	30 - 2,000	50 - 115	6,000 - 20,000
LED	0.05 - 0.1	10 - 30	40,000 - 100,000
Source : Schneider Electric

Comparison of Common Lamps Used in Electrical Installations

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Below are the characteristics of the common lighting technology in use in different electrical installations. Also stated are their place of application, advantages and disadvantages:

Lighting Technology	Application	Advantages	Disadvantages
Standard Incandescent	Domestic use Localized decorative lighting	Direct connection without intermediate Switchgear. Reasonable purchase price. Compact size Instantaneous lighting Good colour rendering	Low luminous efficiency and high electricity consumption. Significant heat dissipation. Short service life.
Halogen Incandescent	Spot lighting. Intense lighting	Direct connection Instantaneous efficiency Excellent colour rendering	Average luminous efficiency
Fluorescent tube	Shops, offices, workshop. Outdoors	High luminous efficiency. Average colour rendering	Low light intensity of single unit. Sensitive to extreme temperatures
Compact fluorescent lamp	Domestic use. offices. Replacement of incandescent lamps	Good luminous efficiency. Good colour rendering	High initial investment compared to incandescent lamps
HP Mercury Vapor	Workshops, halls, hangars. Factory floors	Good luminous efficiency. Acceptable colour rendering. Compact size Long service life	Lighting and relighting time of a few minutes
High-Pressure Sodium	Outdoors Large halls	Very good luminous efficiency	Lighting and relighting time of a few minutes
Low-Pressure Sodium	Outdoors Emergency lighting	Good visibility in foggy weather Economical to use	Long lighting time (5 mins). Mediocre colour rendering.
Metal halide	Large areas Halls with high ceilings	Good luminous efficiency. Good colour rendering. Long service life.	Lighting and relighting of a few minutes
LED	Signaling (3-colour traffic lights, exit signs and emergency lighting	Insensitive to the number of switching operation. Low energy consumption. Low temperature	Limited number of colors. Low brightness of single unit

Typical Power Factors for Common Electrical Loads

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Power factor is very critical for calculating or measuring the electrical power consumed by an electrical device on an alternating current supply. To be able to determine electrical power on alternating current (AC) systems, you need to know the power factor of the electrical load. Below is listed the  typical power factors for common electrical loads:

Electrical Load	Power Factor (CosՓ)	Reactive Demand Factor (TanՓ)
Transformers (No load condition)	0.1 - 0.15	9.9 - 6.6
Motor (Full load)	0.7 - 0.85	1.0 - 0.62
Motor (No load)	0.15	6.6
Metal Working Apparatuses:
Arc Welding	0.35 - 0.6	2.7 - 1.3
Arc Welding  Compensated	0.7 - 0.8	1.0 - 0.75
Resistance Welding	0.4 - 0.6	2.3 - 1.3
Arc Melting Furnance	0.75 - 0.9	0.9 - 0.5
Fluorescent Lamps:
Compensated	0.9	0.5
Uncompensated	0.4 - 0.6	2.3 - 1.3
Mercury Vapor Lamps	0.5	1.7
Sodium Vapor Lamps	0.65 - 0.75	1.2 - 0.9
AC DC Converters	0.6 - 0.95	1.3 - 0.3
DC Drives	0.4 - 0.75	2.3 - 0.9
AC Drives	0.95 - 0.97	0.33 - 0.25
Resistive Load	1	0

Checklist for Selecting and Order an Electric Motor

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The two most important factor to consider when selecting an electric motor are:
1. The electricity supply to which the motor will be connected - AC or DC. If AC three phase or              single phase.
2. Type of enclosure or housing

Type of Electric Motor Enclosure
There are two basic enclosure options available:  drip proof in steel or totally enclosed, in aluminium, steel and cast iron.
The totally enclosed fan cooled (TEFC) motor is the predominant standard for industrial applications, today. The versatile TEFC is fully enclosed within the motor frame, with cooling air directed over it by an externally mounted fan.

Other Key Factors Required for Motor Selection
Loading (KW)
Loading is determined by the equipment to be driven, and the torque available at the shaft. Electric motors have standard outputs per frame size from which any KW loading required can be selected from.

Speed
Choose the required speed of the motor. The induction motor is a fixed single speed machine. Its speed is dependent on the frequency of the electricity supply and the stator winding design. The no load speed of an induction motor is slightly lower than synchronous speed due to the no load losses in the machine. Full load speed is typically a further 3-4 per cent lower than no load speed.

Mounting
The mounting position must always be given when a motor is to be selected. Improper motor mounting can affect performance.

Power Supply
The supply voltage and frequency must be given when selecting an Electric motor

Operating Environment
This is one of the major factors that affect motor performance. The environment in which the motor is to operate is an important factor to consider when selecting a motor, as the ambient temperature, humidity and altitude can all affect performance

Checklist for Ordering a Fixed Speed TEFC Motor:

1. Power Supply

Voltage (Volts)

No. of Phases

Frequency (Hertz)

2. Power Rating

KW

3. Speed

Rev/min

No. of Poles

4. Duty

Type

Mounting IM

5. Motor Drive

Direct

Belt

6. Insulation Class/Temperature Rise

Insulation Class

Temperature Rise (oC)

7. Torque Type

Quadratic

Constant

8. Environmental Conditions

IP Rating

Ambient Temperature (oC)

Relative Humidity

Checklist for Ordering a TEFC Variable Speed Electric Motor

1. Power Supply

Voltage (Volts)

No. of Phases

Frequency (Hertz)

2. Power Rating

KW

3. Speed

Rev/min

No. of Poles

4. Duty

Type

Mounting IM

5. Motor Drive

Direct

Belt

6. Insulation Class/Temperature Rise

Insulation Class

Temperature Rise (oC)

7. Torque Type

Quadratic

Constant

8. Environmental Conditions

IP Rating

Ambient Temperature (oC)

Relative Humidity

9. Variable Speed Drive Specifications
a. Type of Controller	Direct Torque Control (DTC)	Pulse Width Modulation (PWM)
b. Speed Range	Maximum Rev/min	Minimum Rev/min
c. Absolute Power (KW)	Maximum (KW)	Minimum (KW)
d. Output Fitters	Fitted	Non-Fitted
e. Maximum Cable Length (Meters)	Cable length (m)

Electric Motor Standards as Defined By the IEC and the Harmonized European Standard

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Are you working with electric motors or there is the need to specify motors and you need to know what standard applies to what area of electric motors? The table below will be of great help as it itemizes the basic standards that define all areas of electric motor design, construction and installation:

International Standard IEC	Harmonized European Standard	Description
IEC 60034-1 +A1 and A2	EN 60034-1+A1, A2 and All	Rotating electric motors. Part 1: Rating and design
IEC 60034-2+A1, A2 and IEC 60034-2A	EN 60034-2 + A1 and A2	Rotating electric motors. Part 2: Measuring methods to determine the loss and the efficiency of electric motors (except machines for traction vehicles)
IEC 60034-5	EN 60034-5	Rotating electric motors. Part 5: Enclosure class for rotating electric motors.
IEC 60034-6	EN 60034-6	Rotating electric motors. Part 6: Cooling (IC code)
IEC 60034-7+A1	EN 60034-7+A1	Rotating electric motors. Part 7: Classification of types of construction and mounting (IM code)
IEC 60034-8	EN 60034-8	Rotating electric motors. Part 8: Terminal marking and direction of rotation
IEC 60034-9	EN 60034-9	Rotating electric motors. Part 9: Noise limits
IEC 60034-11	-	Thermal protection
IEC 60034-12	EN 60034-12	Rotating electric motors. Part 12: Start capacity of three-phase induction motors.
IEC 60034-14	EN 60034-14	Rotating electric motors. Part 14: Mechanic vibration for machines with drive shaft heights of 56mm or more. Measuring, estimate and vibration limits
IEC 60038	-	IEC Standard Voltages.
IEC 60072-1	EN 50347	Dimensions and output power for rotating electric motors. Part 1: Frame size 56 to 400 and flange size 55 to 1080.
IEC 62114	-	Electrical insulation systems
-	EN 50102	Degrees of protection for enclosures for electrical equipment against external mechanic strokes. (IK-code)
IEC 60072-1	EN 50347	Three-phase induction motors for standard use with standard dimensions and output power. Frame size 56 to 315 and flange size 65 to 740.
Other Standards
DIN 51825		Lubricant; lubricating grease k; classification and requirement (1990-08)
DIN 44082		Thermistors; PTC sensors; thermal protection of machines; climate categorization HFF (1985 -06)
ISO 2409	EN ISO 2409	Paints and enamels. Grid cut value.
-	EN ISO 3743-2	Definition of sound power level. Minor removable sources of noise. Engineering method. Part 2: Rooms with sound control
-	EN ISO 4871	Declaration and verification of noise from machines and equipment.
-	EN ISO 11203	Noise from machines and equipment. Measurement of sound pressure by the operator's ear (noise emission). Calculation on the basis of sound power level.

Common Ingress Protection (IP) Ratings for Electric Motors

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Enclosures of electrical equipment, per characteristics where they will be installed and their maintenance accessibility, should offer a certain degree of Protection also known as Ingress Protection (IP). Standard IEC 60034-5 defines the degrees of protection of electrical equipment by means of the characteristic letters IP, followed by two characteristic numerals. NEMA also defines IP ratings for enclosures. Read IEC Ingress Protection Ratings.  Read also : NEMA Ingress Protection Ratings 

The IEC and NEMA IP ratings are defined for all spectrum of equipment used in an environment where dust, particles, water etc can compromise their performance. However specifically for motors, the standards define the below listed commonly used IP ratings such that there can be no misinterpretation:

Motor	Degree of Protection	First Characteristic Numeral		Second Characteristic Numeral
		Protected Against Accidental Contact	Protected Against Solid Objects	Protected Against Water
Open Motors	IP00	Non-Protected	Non-Protected	Non-Protected
	IP02	Non-Protected	Non-Protected	Protected against dripping water even when tilted 15° vertically
	IP11	Protection against accidental contact with the hand	Ingress of solid objects exceeding 50mm in diameter	Protection against dripping water falling vertically
	IP12	Protection against accidental contact with the hand	Ingress of solid objects exceeding 50mm in diameter	Protected against dripping water even when tilted 15° vertically
	IP13	Protection against accidental contact with the hand	Ingress of solid objects exceeding 50mm in diameter	Protected against dripping water even when tilted 60° vertically
	IP21	Protection against the touching with the finger	Ingress of solid objects exceeding 12mm in diameter	Protection against dripping water falling vertically
	IP22	Protection against the touching with the finger	Ingress of solid objects exceeding 12mm in diameter	Protected against dripping water even when tilted 15° vertically
	IP23	Protection against the touching with the finger	Ingress of solid objects exceeding 12mm in diameter	Protected against dripping water even when tilted 60° vertically
Closed Motors	IP44	Protection against the touching with tools	Ingress of solid objects exceeding 1mm in diameter	Protection against splashing water from any direction
	IP54	Protection against contacts	Protection against accumulation of harmful dust	Protection against splashing water from any direction
	IP55	Protection against touches	Protection against accumulation of harmful dust	Protection against any water jets from any direction

For special and more dangerous areas where electric motors are required to be applied, the following degrees of protection are commonly used:
IPW 55 (Weather protection)
IP56 (Protections against water jets)
IP65 (Totally protected against dust)
IP66 (Totally protected against dust and water jets).

Basics of Coaxial Cables Used in Electronic and Computer Systems

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A coaxial cable consists of four basic parts:

• Inner conductor (center conductor)
• Outer conductor (shield)
• Dielectric, which separates the inner and outer conductors
• Jacket, which is the outer polymer layer protecting the parts inside

Parts of a Typical Coaxial Cable Photo Credit : ANIXTER CABLES

The following characteristics/properties help to define a coaxial cable as applied in electronic systems and Computer Systems:

1. Characteristic impedance

2. Voltage Standing-Wave Ratio (VSWR)

3. Velocity of Propagation

4. Voltage Rating

5. Operating Temperature

Characteristic Impedance

The characteristic impedance of a coaxial cable is a function of its geometry and materials. Characteristic impedance is independent of length and typically ranges from 35 to 185 ohms. The most common values are 50, 75 and 93 ohms. The characteristic impedance of a cable is not the same as the  impedance of the conductors in a cable, which is dependent on length.

The most efficient transfer of energy from a source to a load occurs when all parts of the system have the same characteristic impedance. To have better performance with coaxial cable, there is need for impedance matching especially critical at higher frequencies, where the consequences of mismatches are more severe.

Voltage Standing - Wave Ratio (VSWR)

The voltage standing-wave ratio (VSWR) is a measure of the standing waves that result from reflections. It expresses the uniformity or quality of a cable’s characteristic impedance. Uniformity is also measured as structural return loss (SRL).

Velocity of Propagation

Velocity of propagation is the speed at which electromagnetic energy travels along the cable. In free space or air, electromagnetic energy travels at the speed of light, which is 186,000 miles per second. In other materials, however, the energy travels slower, depending on the dielectric constant of the material. Velocity of propagation is expressed as a percentage of the speed of light. For example, a velocity of 65 percent means that the energy travels at 120,900 miles per second – or 35 percent slower than in free space. The dielectric (insulation) separating the two conductors determines the velocity of propagation. Although the electromagnetic energy travels in the dielectric, the current associated with the energy travels primarily on the outside of the center conductor and the inside of the outer conductor (shield).

The two conductors bind the energy within the cable. Consequently, the quality of the dielectric is important to efficient, speedy transfer of energy. Speed is important to engineers who must know the transit time of signals for digital transmission.

Voltage Rating

This is the maximum voltage the cable is designed to handle.

Operating Temperature Range

These are the minimum and maximum temperatures at which the cable can operate.

Types of Coaxial Cables

There are many types of coaxial cables but four types are commonly used namely:

1. Flexible Coax

2. Semirigid Coax

3. Triaxial 

4. Dual Coax

There is also Twinaxial (Twinax) Cable used in high-speed, balanced-mode multiplexed transmission in large computer systems.

Flexible Coax

The most common type, flexible coax has a braided outer conductor (shield) of extremely fine wires. While the braid makes the cable flexible, it does not provide complete shielding – energy (RF signals) can leak through the shield via minute gaps in the braid. To combat this, many cables have several layers in the outer conductor. In addition, thin foils are sometimes used to supplement the braid to provide better coverage for greater shielding effectiveness. The greater the coverage, the better the shield

Semirigid Coax

Semirigid coax has a solid, tubular metallic outer conductor, similar to a pipe. This construction gives the cable a very uniform characteristic impedance (low VSWR) and excellent shielding, but at the expense of flexibility.

Triaxial Cable (Triax)

This coax has two outer conductors (shields) separated by a dielectric layer. One outer conductor (shield) serves as a signal ground, while the other serves as earth ground, providing better noise immunity and shielding. One caution: Do not confuse a flexible cable having a multilayer outer shield with triaxial cable.

Dual Coax

This cable contains two individual coaxial cables surrounded by a common outer jacket.

Shown below are the four basic types of coaxial cables commonly used

Common Types of Coaxial Cables - Photo Credit : ANIXTER CABLES

Twinaxial Cable (Twinax)

Twinax has a pair of insulated conductors encased in a common outer conductor (shield). The center conductors may be either twisted or run parallel to one another. In appearance, the cable is often like a shielded twisted pair, but it is held to the tighter tolerances common to fixed-impedance coaxial cable. A common use of twinax is high-speed, balanced-mode multiplexed transmission in large computer systems. Balanced mode means that the signal is carried on both conductors, which provides greater noise immunity.

A Typical Twinaxial Cable - Photo Credit: ANIXTER CABLE

Basic Parts of a Three Phase (3-Փ) Squirrel Cage Induction Motor

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The diagram below shows all the basic parts that makes up an AC induction motor. These basic parts work together to ensure the smooth performance of this highly efficient electrical device:

Parts of a three-phase Induction Motor - Photo Credit: WEG MOTORS

Stator Parts

As shown in the diagram above, the parts 1, 2 and 8 makes up the stator of the three-phase Induction motor:

1 – Motor Frame. This is the supporting structure of the motor assembly; manufactured        

     of  iron, steel, die-cast Aluminium, resistant to corrosion and with cooling fins.

2 – Lamination Core. This part is constructed with magnetic steel plates and houses the 

     motor windings.

8 – Three - phase Windings. This comprises three equal sets of coils, one se set for each 

     phase, forming a balanced three-phase system when connected to a three-phase        

     power supply.

Rotor Parts

The rotor of a three-phase squirrel cage Induction motor consists of a set of non-insulated bars that are interconnected by short-circuit rings. What characterizes an induction motor is the fact that only the stator is connected to the power supply. The rotor is not power supplied externally and the currents that flow through it are induced electromagnetically by the stator from which comes the induction motor name.

The parts 3, 7 and 12 makes up the rotor of the three-phase motor:

7 – Shaft. It transmits the mechanical output developed by the motor.

3 – Laminated Magnetic Core. The rotor laminations have the same characteristics of the       

     stator laminations.

12 – Rotor Bars and Short Circuit Rings. These are Aluminium die castings formed as one 

       piece. They enable the rotation of the motor through induction of electromagnetic 

       current 

Other Parts of The Motor

Below are listed other critical parts of the three-phase squirrel cage induction motor:

4 – End Shields

5 – Fan for cooling motor

6 – Fan Cover.

9 – Terminal Box. This houses the electrical terminals of the motor.

10 – Motor terminals

11 – Bearings. These support the rotation of the rotor.