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Measuring light levels

Measuring light levels

Measuring light levels

I've inherited a trial of a energy saving device (voltage reduction) for high mast lighting, our lighting specialist has retired and gone to live in Spain.

The spec calls for horizontal illuminance of 20 lux with uniformity factor of 4:1 and verical illuminance of 20 lux at a hight of 2m.

I need to establish the reduction in light level when the supply is reduced from 230V to 200V.

When I've measured light levels before the sensor has been pointed up, so I assume this is the vertical measurement.

How do I measure horizontal illumination, just turn the device through 90deg?

As you may have guessed I'm not a lighting specialist.

RE: Measuring light levels

Nope, horizontal illumination is that which illuminates a horizontal surface, so your sensor pointing straight up would be measuring horizontal illumination.

RE: Measuring light levels

davidbeach is right.  Vertical illumination would be measured say...against a wall with the sensor pointing sideways.

RE: Measuring light levels


Thank you for that I was 90 deg out. That's engineering something new every project


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