Type of Lighting Bulbs (Shapes and Sizes) Part-4

What is difference between R,BR,MR and PAR bulbs

(1) Difference between an R and BR Bulb

  • There is confusion between selecting R and BR type of Bulbs.
  • There is minor difference between R and BR type Bulb.
  • Both types of Bulbs have a reflector flood, and that is what the R stands for in the code.
  • The R is an old design for reflectors that are not as energy efficient as a BR reflector.
  • The BR was designed to replace the older R.
  • For same Light output and size in length and width, BR Bulb use less watts (due to the reflector in a BR is more directed) hence BR Bulb produce less heat and more efficient.
  • Both of these lamp types are interchangeable.
  • BR is an upgraded version of R 

(2) Difference between PAR and BR / MR Bulb:

  • The main difference between PAR and MR is according to its Size, variety, and heat transformation.
  • The primary difference between these bulbs is according to Beam Angle, internal construction and as per Reflector.
  • Different Type of Beam Angles.
  • BR (for bulged reflector) bulbs are lamps with “wide flood” beam angles, which means that they provide more than a 45 degree angle when lighting an area.
  • PAR (Parabolic Aluminized Reflector) bulbs are available in these angles:
  • Narrow spot (5 to 15 degrees)
  • Spot, (16 to 22 degrees)
  • Narrow flood,( 23 to 32 degrees)
  • Flood, (33 to 45 degrees(
  • Wide flood beam, over 45 degrees.

  • Different Type of Reflector and Application of Bulb.
  • The BR bulbs have a frosted/patterned coating of reflector (for broad beam angle ) allows to less concentrated light and provides better coverage thus eliminating shadows in the intended area hence BR Bulb produces less shadow than PAR bulbs.
  • BR Bulbs are commonly used indoors in household ceilings like in kitchens, family rooms, and stair lighting with high ceilings with recessed type.
  • The reflective surface of PAR does not allow light to spread much further than the angle of the beam spread hence PAR lamps deliver strong, narrow to wide, directional light , which is little harsher where the light starts and where it ends.
  • A PAR bulb is used in indoor/outdoor security lighting, theatre, performance sets, and spot-lighting signs and restaurant lighting applications as well.
  • Different Type of Construction and Heat dissipation.
  • BR bulbs are a common reflector lamp with a bulged reflector. They are incandescent, LED bulbs. The sides of the outer part of the blown glass bulb are coated with a reflecting material that directs light. The light transmission pattern can be clear, frosted, or even patterned.
  • PAR bulbs are incandescent, tungsten-halogen, metal halide, LED Bulbs. They have a hard glass cover which is hermetically (airtight) sealed to the reflecting surface. Inside there is a lenses that controls beam spread and cannot be altered in position in relation to the filament. There are flood bulbs and spot bulbs. Flood bulbs diffuse or scatter light, while spots focus all light in one direction.
  • MR type bulbs have dichotic glass reflectors while PAR bulbs have aluminized glass reflectors which direct the heat generated by the bulb to the front of the bulb. Due of this, PAR bulbs are not suitable for ceiling installations of 8 feet or lower.
  • PAR bulbs also produce more directional yet duller lighting and have a standard, medium screw-in type of base and work in medium sized E26 sockets.
  • MR on the other hand, generates heat to the rear of the bulb and produces a lot more light for the wattage because of the multi-faceted reflector (MR).

Lighting Bulb according to HID Technology:

(1) E (Elliptical) Type HID Bulbs (Code: E)

  • E means HID Type light bulb that has a shape of “Elliptical”.
  • E Type Halogen light bulbs can be used to replace incandescent light bulbs. High intensity discharge light bulbs.
  • Nomenclature:
  • Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.
  • E20 bulb: 20/8 = 2-1/2″ diameter
  • Lighting direction: illuminates its light in one direction.
  • Bulb Technology: incandescent, CFL, High Intension Discharge Lamps, Metal Halide Lamp, Sodium Discharge, Mercury Vapor Lamp and LED.

(2) ED (Elliptical Dimple) Type HID Bulbs (Code: ED)

  • ED means “Elliptical Dimple”.
  • ED light bulbs have an elliptical shape to house the arc tube of a high intensity discharge light bulb.
  • They are not as efficient as their alternatives, but their use may be dictated by color rendering requirements. The lamps require only ballast for additional control.
  • Inside surfaces coated with europium-activated phosphor which converts the UV elements in ’warm’ light to produce a cool white light. They are an acceptable alternative to fluorescent lighting
    Nomenclature: ED17.
  • Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.
  • EDR20 bulb: 20/8 = 2-1/2″ diameter
  • Lighting direction: illuminates its light in one direction.
  • Bulb Technology: High Intension Discharge Lamps, Metal Halide Lamp, Sodium Discharge, Mercury Vapor Lamp and LED.
  • Applications:

  • ED light bulbs are used in sports arenas, high bay industrial lighting, parking lots and garages and car dealerships.
  • These lamps are used in some industrial, warehousing applications as a floodlight and other suitable light fittings with appropriate ballast gear.
  • FEATURES & BENEFITS
  • Metal Halide HID light bulb produces high light output
  • Ideal for various commercial and industrial applications where color rendering is important
  • RECOMMENDED USES
  • Retail areas
  • Area lighting
  • Accent lighting
  • Sports lighting
  • Security lighting
  • Parking garages

(3) ER (Elliptical Reflector) Type HID Bulbs (Code: ER)

  • ER means “Elliptical Reflector”.
  • In ER bulb, the elliptical reflector increases the overall lumen output by redirecting side light of Bulb (Which is normally lost) to the redirect it to the forward Side of Bulb.
  • Elliptical (ellipsoidal) reflector light bulbs are uniquely designed to project light further than other reflector bulbs. They are a great option for use in deep recessed can lights as they lose less light in baffles than standard BR or R type bulbs. 
  • ER halogen light bulbs can be used to replace incandescent light bulbs. High intensity discharge light bulbs.
  • An incandescent lamp with a built-in elliptically-shaped reflecting surface. This shape produces a focal point directly in front of the lamp which reduces the light absorption in some types of luminaires. It is particularly effective at increasing the efficacy of baffled down lights.
  • Nomenclature: ER28, ER37.
  • Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.
  • ER20 bulb: 20/8 = 2-1/2″ diameter
  • ER30 bulb: 30/8 = 3-3/4″ diameter
  • ER36 bulb: 36/8 = 4-1/2″ diameter
  • Lighting direction: illuminates its light in one direction.
  • Bulb Technology: incandescent, CFL, High Intension Discharge Lamps, Metal Halide Lamp, Sodium Discharge, Mercury Vapor Lamp and LED.

  • Applications:
  • The most common size is ER30. These light bulbs are used for down lighting in recessed cans for residential, hotel, and office applications.


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