Electric Data ( Glossary )

Design volts (V) show the voltage at which a lamp is designed for rated ampere, candlepower and laboratory-life characteristics.

Design amperes (mA) are the current flowing through a lamp when operated at its design voltage. It is subject to nominal manufacturing tolerances ± 10 %

Mean spherical candle power (MSCP) The MSCP is the generally accepted method used to indicate the brightness of miniature lamps; it is the total value emitted from a lamp placed at the center of a circle having a specified diameter. The standard lamp calibrated by National Bureau of Standards is used in determining this value. MSCP can be converted into lumens by multiplying MSCP by 4 π pi (12,57 × MSCP = lumens )

Average laboratory life (h) Lifetime indicated is based upon test data recorded under strictly controlled laboratory conditions. Under normal operating conditions, however, lifetime may be shorter due to factors such as voltage fluctuation, shock, vibration, temperature, and other environmental and operation conditions.

MOL (Maximum Overall Length) MOL is measured from the bottom of the base ( or bottom of glass tip for unbased lamps) to the top of the envelope.

MOD (MaximumOutside Dia.) MOD is a measurement across the largest part of the envelope.

LCL (Light Center Length) LCL is a measurement from the geometric center of the filament to : Flange Base - top of flange, Grooved Base - center of groove, Bi-Pin Base - flat bottom, Screw Base - bottom of center contact, Bayonet Base - top of base pin, Wedge Base - center of notch, SC or DC Prefocus Base -bottom of indentations on prefocus collar, Wire Terminal - not specified.

Filament Shapes The filament is the light emitting portion of the lamp. Its configuration is identified by the prefix letter - S for straight, C for coiled and CC for coiled coil ( double coil).

Quality Control

The lamp features highly reliable design for life-, vibration-, shock-, drop-, vacuum-, and atmospheric resistance- testing to ensure durability.

Life test

Life time of lamps is generally determined by the following equation.

IEC Specification (International Electrical Commission) "Tungsten Filament Lamps for General Use" The equivalent life for rated voltage shall be determined in accordance with the following equation.

Lo = L ( V ÷ Vo ) ⁿ

Lo ............................Life at rated voltage

L  .............................Life at test voltage

Vo ............................Rated voltage

V ..............................Average voltage during life test

n = 13 vacuum lamps; 14 gas filled lamps

IES Specification (Illumination Engineering Society)

"Lighting Hand Book"

Lo = L ( V ÷ Vo ) ⁿ

n = 13.5 vacuum lamps; 13.1 gas filled lamps

Vibration test

All specification requirements must be met before and after vibration for 30 minutes. The test condition :

1. Frequency cycled : 2,000 rpm
2. Amplitude : 2mm
3. Vibration shall be up and down, forward and backward, right and left with the lamps mounted on a horizontal plane.

Shock test

All specification requirements must be met before and after shock test for3 times. The test condition let the lamp mounted on a board and force the lamp drop from 20cm high onto the bottom board.

Aging

"Aging" is one of the most important and indispensable procedures for stabilizing the quality of the lamps after production.

Each lamp, after being moved away from production line, is continuously lighted for 2-10hours in design voltage according to its average life and application. This is called "aging". During the first few lighting hours the characteristics  of the filament of an incandescent lamp change unstably. All specification requirements must be met by selection after aging of a lamp. Furthermore, aging is an important method to find out short circuit and vacuum leakage, which can not be found within short time of lighting. Only after aging will the filament of a vacuum-deficient lamp evaporate and cause the blackening of the inside bulb glass which can be discerned with naked eyes.