Bosch Power Tools GCL25 manual Working without Automatic Levelling see figure F

To deactivate the automatic shut-off, keep

the operating mode button 2 pressed for at least 3 s (while the measuring tool is switched on). Deactivation of the automatic shut-off is confirmed by brief flashing of the laser beams.

!WARNING Do not leave the switched o n m e a s u r i n g t o o l

unattended and switch the measuring tool off after use. Other persons could be blinded by the laser beam. To activate the automatic shut-off, switch the measuring tool off and then on again.

Operating Modes

The measuring tool has four operating modes between which you can switch at any time:

–Cross-line and point operation: The measuring tool generates a horizontal and a vertical laser line facing toward the front as well as a vertical point beam each facing upward and downward, and a horizontal point beam each facing toward the front and to both sides.

–5-point operation: The measuring tool generates a vertical point beam each facing upward and downward, as well as a horizontal point beam each facing toward the front and to both sides.

–Horizontal line operation: The measuring tool generates a horizontal laser line facing frontward.

–Vertical line operation: The measuring tool generates a vertical laser line facing frontward.

All point beams run at a 90° angle to each other; the laser lines also cross each other at a 90° angle. After switching on, the measuring tool is in cross-line and point-line operation. To change the operating mode, press the operating

mode button 2.

All operating modes can be selected both with and without automatic levelling.

Automatic Levelling

Working with Automatic Levelling (see figures C–E) Position the measuring tool on a level and

firm support, attach it to the holder 15 or to the tripod 16.

When working with automatic levelling, push the On/Off switch 4 to the “ on” position.

soon as the measuring tool is within the self- levelling range of ±4°, the laser beams light up continuously. In case of ground vibrations or position changes during operation, the measuring tool is automatically levelled in again. To avoid errors by moving the measuring tool, check the position of the laser beams with regard to the reference points upon re-levelling.

Working without Automatic Levelling (see figure F)

For work without automatic levelling, push the On/Off switch 4 to the “ on” position. When the automatic levelling is switched off, the laser lines flash continuously.

When automatic levelling is switched off, you can hold the measuring tool freely in your hand or place it on an inclinded surface. The laser beams no longer necessarily run vertical to each other.

Levelling Accuracy

Influences on Accuracy

The ambient temperature has the greatest influence. Especially temperature differences occurring from the ground upward can divert the laser beam.

As thermal fluctuation is largest close to the ground, the measuring tool, if possible, should be mounted on a commercially available tripod and placed in the centre of the working area.

Apart from exterior influences, device-specific influences (such as heavy impact or falling down) can lead to deviations. Therefore, check the accuracy of the measuring tool each time before starting your work. When the accuracy of the horizontal point beams is within the maximum allowed deviation, then the accuracy of the vertical point beams and the laser lines is thus also checked. Should the measuring tool exceed the maximum deviation during one of the tests, please have it repaired by a Bosch after-sales service.

After switching on, the automatic levelling f u n c t i o n a u t o m a t i c a l l y c o m p e n s a t e s irregularities within the self-levelling range of ±4°. The levelling is finished as soon as the laser points or laser lines do not move any more. If the automatic levelling function is not possible, e.g. because the surface on which the measuring tool stands deviates by more than 4° from the horizontal plane, the laser beams flash. This alarm is deactivated within 10 s after switching on, in order to allow adjustment of the measuring tool.

Set up the measuring tool in level position and wait for the self-levelling to take place. As

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GCL 25 Manual with translations.indd 9 4/24/12 8:29 AM