Only if it does not immerse! The instrument is drip-proof but because of the measuring principle not water-proof. For protection, the accessories or, if necessary, a plastic bag can be used. If water has entered unintentionally, make sure that the instrument can dry quickly (by opening the battery lid, removing the battery, putting the handheld device up-end, drying). Please keep also the inside of the case dry.

 Yes – deposit the hose reel in the building and transmit the level from inside to outside or the other way round.
When overcoming walls or obstacles, please make sure that the altitude difference between hose reel and handheld device does not exceed + 3 metres – if necessary, please deposit the hose reel on some elevation.

  A sag between the holders is allowable. Please also note the directions for the application of the instrument outside of buildings. Generally, you must lead the hose that way that it does not impair the passages' safety and cannot drop off over a greater length. Levelling works should be carried out quickly and with check measurements in order to finally remove the instrument from the scaffolding.

  For most of the applications, this function is not required. Where the difference in altitude can be measured with a measuring tape or folding rule, it should be proceeded this way.
The altitude calibration changes by a few per mil (1..2) according to the region or over a long time period as well. Only if altitude differences accurate to the millimetre are to be obtained, an occasional check of the altitude calibration is recommended. Two vertical line up points with exactly 1000 mm altitude difference (1m-water level, 1m-pieces of timber) are suitable for this.
A coarsely adjusted altitude calibration can be reset to the factory setting per ->Sett -> r.
The altitude calibration always uses millimetre!

  Only if deviations exceeding the allowable tolerance limits are detected at repeated check measurements or if there is another detectable defect.
Important:
- while measuring, the hose reel must lie solidly
- the pressing screw must be correctly adjusted to the measurement point
- do not measure too hastily, please note the directions of the operating instructions.

Yes, but the case should lie solidly and not at an angle. If you pull out more length of the hose, the level can be shifted by approximately 1 millimetre.

About 250… 300 hours in measuring mode i.e. at an average usage about 2 years.
Alkaline batteries are preferable – accumulators are not applicable. 

Just outdoors – outdside of buildings.
- at longer and more intensive insolation, the instrument can reach critical temperatures!

- also great changes in temperature over sections of the hose reduce reproducibility – hence do not lead the hose over hot surfaces.

Under unfavorable conditions carry out measurements only in compliance with the directions for exact levelling.

Only if the hose is so greatly damaged that liquid is leaking out, the instrument is to be transmitted to the technical service. The liquid is neutral and not toxic.
Scratch marks or adhesive residues on the hose do not affect the measuring system.
The hose is double-walled, solid, it does not break, it can be stepped on or rolled over.

If the pressure-spindle is not in the mode "measure" during levelling, deviations of some millimetres are possible.

If the instrument was being kept for several days or weeks without having turned the pressure-spindle into the mode "store", bubbles can occur in case of subsequent severely hose movements. Therefore, the instrument should be correctly stored 1-3 days before the next usage. In case of wrong storage, the flashing module of the hose reel reminds of the incorrect (spindle-)position through the sound of a siren at an interval of one to two days (see manual section "special indications").

Mostly, mechanical parts are available as spare parts. The fittings on the case can also be replaced by the user (snap-in/ joints, shutters and grip). These can be ordered at specialized dealers. The same applies to accessory parts.

Preferably if the paint or mortar has not dried yet. In order to avoid scratch marks, use some water and a wet brush. Do not use any solvents or benzine for cleaning!

The slope [%] of a surface is determined by the measurement of the height-difference at two points and corresponds to the height-difference divided through the horizontal distance of the measure points multiplies with 100.
A height-difference of 35 mm in the distance of 1000 mm corresponds to an inclination of 3,5%.
The corresponding angle-measurement in degree can be determined with the table on the rear of the unit: 35 mm/ms correspond to 2 degrees. With small angle < 10° inter-dimensions can be determined by addition of the values.
An illustration can be found here in PDF format.