GPT-3000 SERIES - FLT Geosystems

17 CHECK AND ADJUSTMENT17.3.1Checking /Adjusting the Plate LevelAdjustment is required if the axis of the plate level is not perpendicular to the vertical axis.● Check1) Place the plate level parallel to a line running through the centers of two leveling screws, say, A andB. Use these two leveling screws only and place the bubble in the center of the plate level.2) Rotate the instrument 180° or 200g around the vertical axis and check bubble movement of theplate level. If the bubble has been displaced, then proceed with the following adjustment.Plate levelLeveling screwLeveling screw B● Adjustment1) Adjust the level adjustment capstan screw, with the accessory adjusting pin and return the bubbletowards the center of the plate level. Correct only one-half of the displacement by this method.2) Correct the remaining amount of the bubble displacement with the leveling screws.3) Rotate the instrument 180° or 200g around the vertical axis once more and check bubblemovement. If the bubble is still displaced, then repeat the adjustment.Level adjustmentcapstan screwTotal amount of displacementHalf amount of displacement17.3.2Checking /Adjusting the Circular LevelAdjustment is required if the axis of the circular level is also not perpendicular to the vertical axis.● Check1) Carefully level the instrument with the plate level only. If the bubble of the circular level is centeredproperly, adjustment is not required. Otherwise, proceed with the following adjustment.● Adjustment1) Shift the bubble to the center of the circular level, by adjusting three capstan adjustment screws onthe bottom surface of the circular level, with the accessory adjusting pin.Capstan adjustmentscrewsBottom of the baseCircular level17-8