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Light Fastness Tester Instrument Configurations
The range of standard instrument configurations for the light fastness tester (LFT) is shown below with the major accessories and upgrades shown following the descriptions of the instruments.
Instrument Configuration Summary
LFT1E–500 - Basic Model
This model fades samples approximately 3·4 times faster than daylight alone. As supplied, a maximum of fifty type 'C' cells provides for the convenient exposure of up to fifty samples at one time, although with additional accessories the maximum is readily increased to 134 samples.
LFT1E–400 - Rapid Fade Model
This model fades samples approximately 5·4 times faster than daylight alone. As supplied, a maximum of fifty type 'C' cells provides for the convenient exposure of up to fifty samples at one time, although with additional accessories the maximum is readily increased to 134 samples.
LFT4E - Very Rapid Fade Model
This model fades samples approximately 15·5 times faster than daylight alone. No exposure cells are supplied as standard, but using the large cells permits a maximum of 120 samples to be processed at one time. There is no provision for using type C cells.
LFT5E - Combined Model
This model combines the facilities of the LFT1E–500 and the LFT1E–400 and so fades samples at a rate appropriate to the lamp in use. Additionally, a resettable timer–counter is fitted to permit the instrument to be automatically switched off at the end of the selected test period. No exposure cells are supplied as standard, but using the large cells alone would permit a maximum of 120 samples to be processed at one time, and with accessories the maximum can be raised to 134 samples.
Instrument Accessories Summary
Each instrument is equipped with a relative humidity control fluid filling syringe, and an hours run meter to display the elapsed time. The LFT1E instruments are also supplied as standard with fifty 'C' cells. Alternative types of exposure cell both with and without water–cooling facilities may be chosen as appropriate to the work in hand.
 Type 'A' cell
This accessory permits the holding of ten discrete samples each 1 cm × 5 cm at one time and is water–cooled to keep the sample's temperature down during exposure. A maximum of twelve 'A' cells and fourteen 'C' cells can be fitted into an instrument at the same time, which permits a total of 134 samples to be exposed at one time.
Type 'B' cell
This accessory permits the holding of ten discrete samples each 1 cm × 5 cm at one time but is not water–cooled. A maximum of twelve 'B' cells and fourteen 'C' cells can be fitted into an instrument at the same time, which permits a total of 134 samples to be processed simultaneously.
Type 'AB' cell
This accessory permits the holding of ten discrete samples at one time and is water–cooled to keep the sample's temperature down during exposure. It is intended for relatively thick materials such as carpet or heavy materials. A maximum of twelve 'AB' cells and fourteen 'C' cells can be fitted into an instrument at the same time, which permits a total of 134 samples to be exposed at one time.
Type 'C' cell
This accessory permits the holding of one discrete sample at a time but is not water–cooled. Careful mounting and masking can permit exposure of two discrete samples per C cell. A maximum of fifty 'C' cells can be fitted into an instrument at the same time, which permits a total of 50 samples to be exposed simultaneously.
Type 'CA' cell
This accessory permits the holding of one discrete sample at a time and is water–cooled to keep the sample's temperature down during exposure. A maximum of fifty 'CA' cells can be fitted into an instrument at the same time, which permits a total of 50 samples to be processed at one time.
Close Frame (CF) 
This accessory can mount up to six 'A', 'B', or 'AB' cells close up to the instrument's lamp allowing a maximum of 60 samples to be exposed at one time. The fading rate is multiplied by 5·2 approximately, so raising the effective rates approximately as follows:
LFT1E–500
3·4 >> 17·5
LFT1E–400
5·4 >> 28
LFT4E
15·5 >> 80
LFT5E
As appropriate to the lamp in use.
However, any samples which are affected adversely by the higher temperatures which are reached when using this accessory, should instead be exposed in the instrument's main exposure gallery at the normal lamp–to–sample seperation distance. 
Air Cooled Exchanger (ACE)
This accessory permits the use of a circulating cooling supply which avoids the need for a mains water supply and a drain for the run off. It is used with the 'A', 'AB', and 'CA' cells only.
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