Does the sun affect the measurement result?

No, LTL-X has a built-in Stray Light Compensation effectively ensuring that ambient light from the sun or other light sources does not affect the accuracy of the measurement.

How long time does it take to measure?

To make one retroreflection measurement takes less than 1 second.

Can LTL-X display luminous flux (lumens)?

No, it is not possible to measure luminous flux.

Can I change the fuses if blown?

Yes you can, please see the attached instruction, LTL-X, Fuses.

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How can I prepare the LTL-X for measuring under continuous rain?

You need to mount the enclosed rails beneath the instrument. Please see the attached instruction  LTL-X, Mounting Rails.

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How fast does the battery charge?

The battery is normally fully charged within 1½ hour.

How many measurements can I take with a fully charged battery?

Depends on how the instrument is used; the use of LCD backlight, sound, GPS, printer and the measurements schedule all influence the achievable number of measurements. A fully charged and fresh battery will be able to make around 2.000 measurements.

When do we know that the battery should be replaced?

A fully charged and fresh battery will normally make around 2.000 measurements. If the number of measurements on a fully charged battery falls much below, it is time to replace it.

How long does a battery last before it needs to be replaced?

This depends on use pattern as mentioned above. It not used on a daily basis DELTA generally recommends keeping the battery fully charged maximising the life time, which is normally several years.

Can I change the battery myself?

Yes you can, please see the attached instruction, LTL-X, Battery.

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Can I calibrate the LTL-X myself?

Yes you can by using the calibration unit that comes with the instrument. Please see the attached instruction  LTL-X, Calibration.

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How often does the calibration standard need to be re-calibrated?

If kept dry in storage and taken well care of when used (no dirt, no scratches on the calibration block surface) it can last several years without needing re-calibration. DELTA, however, recommends to have a re-calibration or replacement of the laboratory (black) calibration block done at least every two years to make sure that the calibration of the instruments is correct.

Is there an alternative to sending the calibration unit for re-calibration?

Yes, you can decide to purchase a new calibration unit from DELTA for your instrument, see our price list for details.

How do I know that the calibration block needs re-calibration or needs to be changed?

When the calibration block is scratched, dirty (and cannot be properly cleaned) or otherwise damaged, it is time to replace it.

Does the retroreflectometer itself need to be re-calibrated?

The instrument comes calibrated from the factory. Unless the instrument has been damaged after e.g. being dropped or run over by a vehicle the instrument itself does not need re-calibration.

Instrument service

How often does the LTL-X need to be serviced?

LTL-X is a very robust instrument which can stand daily use without need for service. If you should have an accident with the instruments (being dropped, being hit hard and alike) DELTA recommend servicing the instrument. If you want to be sure the instruments work correctly at all times you may consider an instrument service at DELTA at regular intervals. If the instrument is used every day DELTA recommend these intervals being once a year, if used less often a service every 2-3 years will do. The DELTA service program will soon be available here.

How do I know if/when the instrument needs service?

If the instrument doesn\’t work at all, if the instrument status informs you that it has detected problems (constant errors and/or warnings) or the measurement are obviously wrong, the instrument needs urgent service.

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