AccuLine 40-6537 User manual

Prepared By: Tim Wojo Revision - Date: 0 – 03232009 Page 1 of 15
40-6537 Service Manual
40-6537 Auto-leveling Rotating Laser
Service Manual
Item Description Pages
1.0 Introduction 2
2.0 Overall Unit Assembly 2
2.1 Upper Cover Assembly 3
2.2 Housing Assembly 3
2.3 Main Body Assembly 4
2.4 Core Assembly 5
2.5 Base Assembly 6
3.0 Calibration 6-14
3.1 Horizontal Mode Calibration 7
3.1.1 Quantifying Accuracy Error 7
3.1.2 Characterizing Accuracy Error 8
3.1.2.1 Oblique Error 9-11
3.1.2.2 Taper Error 12
3.1.2.3 Wave Error 13
3.2 Vertical Mode Operation 14
3.3 Alarm Calibration 14
4.0 Electrical Connections 14
5.0 Trouble Shooting Guide 15

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40-6537 Service Manual
1.0 Introduction
This rotating laser is a highly accurate instrument. Out side of a few
customer adjustments (outlined in the owners manual), all performed
only by authorized service personnel. Authorized personnel should
adhere to the guidelines described within this service manual for all
repairs and/or service work. This manual is written with the
assumption that a unit is disassembled or assembled from start to finish.
In reality, only component parts or modules would be replaced during a
repair. Given this, procedures discussed in this manual should be
adjusted according to the repair being made.
2.0 Overall Unit Assembly (40-6537)
1. Remove Rechargeable Battery Pack (9) by turning retaining screw counter clockwise.
2. Remove Upper Cover Assembly (2), and Housing Assembly (11), by removing retaining screws 8.
3. Carefully disconnect ribbon cable of Keypad PCB
4. Remove Handle (3) by removing rubber screw plug (12) and retaining screw (1).
5. Disassemble housing assembly (11) by removing retaining screws (4).
6. Remove Main Body Assembly by removing retaining screws (10) and (5).
Item JLT Part # Description Qty
1 AP1690 ST2.9 x 10 Cross Plate Tapping
Screw
2
2 AP1939 Upper Cover Assembly 1
3 AP1940 Handle 1
4 AP1742 M2.5 x 12 Cross Plate Screw 6
5 AP1026 ST2.9 x 13 Cross Plate Tapping
Screw
2
6 AP1941 Main Body Assembly 1
7 AP1942 Base Assembly 1
8 AP1565 M3 x 14 Cross Plate Screw 4
9 AP1943 Battery Case Assembly 1
10 AP1677 ST2.9 x 8 Cross Plate Tapping
Screw
2
11 AP1944 Housing Assembly 1
12 AP1945 Stopper 1

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40-6537 Service Manual
2.1 Upper Cover Assembly (AP1939)
1. Remove Rechargeable #11 PCB (2-2) by removing retaining screws (2.3)
2.2 Housing Assembly (AP1944)
1. Remove keypads 1 and 2 (11-1) and (11-7) respectively, by peeling off of housing.
2. Remove #2 PCB (11-3) by loosening retaining nuts (11-4).
3. Remove #3 PCB (11-6) by loosening retaining nuts (11-4) and (11-5), respectively.
Item JLT Part # Description Qty
2.1 AP1947 Upper Cover 1
2.2 AP1948 #11 Connecting PCB 1
2.3 AP1843 ST2.2 x 6.5 Cross Plate Tapping
Screw
1
Item JLT Part # Description Qty
11.1 AP1949 Keypad 2 1
11.2 AP1950 M2.5 x 8 Cross Sunk Screw 8
11.3 AP1951 #2 PCB Key Pad 2 1
11.4 AP1538 M2.5 Nut 8
11.5 AP1952 Connecting Nut 4
11.6 AP1953 #3 PCB Keypad 1 1
11.7 AP1954 Housing 1
11.8 AP1989 Keypad 1 1

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40-6537 Service Manual
2.3 Main Body Assembly (AP1941)
1. Remove #4 PCB (6-13) and #5 PCB (6-15) by loosening/removing retaining 6 screws (6-7) and 2 elastic gaskets (6-16)
respectively.
2. Remove #1 PCB (6-6) by loosening/removing 4 retaining screws (6-7).
3. Disassemble top plate assembly (6-2) by removing retaining screw (6-19) and respective elastic gasket (6-18) as well as 6
retaining screws (6-1) and respective elastic gaskets (6-3).
4. Remove Core Assembly (6-4) from Frame Parts 1 and 2 (6-8 and 6-17, respectively) by removing 2 tension springs (6-5).
5. Disassemble Frame Parts 1 and 2 (6-8 and 6-17, respectively) by removing 6 retaining screws (6-12) and they’re respective
elastic gaskets (6-3).
6. Disassemble #8 Alarm PCB (6-10) by removing 2 retaining screws (6-12) and they’re respective spacers (6-11)
Item JLT Part # Description Qty
6.1 AP1513 M3 x 8 Cross Plate Screw 12
6.2 AP1955 Top Plate Assembly 1
6.3 AP1883 3MM Elastic Gasket 12
6.4 AP1956 Core Assembly 1
6.5 AP1957 Tension Spring 2
6.6 AP1958 #1 Main PCB 1
6.7 AP1616 M2.5 x 5 Cross Plate Screw 10
6.8 AP1959 Frame Part 1 1
6.9 AP1960 Bottom Plate 1
6.10 AP1961 #8 Alarm PCB 1
6.11 AP1962 Spacer 2
6.12 AP1493 M2.5 x 8 Cross Plate Screw 2
6.13 AP1963 #4 PCB 1
6.14 AP1964 Connecting Staff Part 1
6.15 AP1965 #5 PCB 1
6.16 AP1915 2.5MM Elastic Gasket 2
6.17 AP1966 Frame Part 2 1
6.18 AP1967 4MM Elastic Gasket 1
6.19 AP1968 M4 x 14 Cross Plate Screw 1

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40-6537 Service Manual
2.4 Core Assembly (AP1956)
1. Disassemble Ball Gimbal Assembly (6-4-22) and Compression Spring (6-4-19) by removing retaining screw (6-4-17) and
respective elastic gasket (6-4-18).
2. Disassemble 2 Sensor assemblies (6-4-20) by removing 4 retaining screws (6-4-1).
3. Disassemble #6 PCB (6-4-12) by removing 2 retaining screws (6-4-9).
4. Disassemble #9 PCB (6-4-16) by removing 2 retaining screws (6-4-9).
5. Disassemble Electric Motor (6-4-10) by removing 2 retaining screws (6-4-9), 2 elastic gaskets (6-4-10), and 2 flat spacers
(6-4-23).
6. Disassemble Rotary Head (6-4-2) by removing 2 retaining screws (6-4-1).
7. Disassemble Prism Assembly (6-4-4) by removing 4 retaining screws (6-4-3).
8. Disassemble 12mm Bearing (6-4-7), Big Gear Assembly (6-4-8), and second 12mm Bearing (6-4-7) by loosening retaining
screw (6-4-6) and turning locking nut (6-4-5) counter-clockwise until it is removed.
9. Disassemble Indicator (6-4-14) by removing 4 retaining screws (6-4-15).
Item JLT Part # Description Qty
6.4.1 AP1647 M2x 5 Cross Plate Screw 6
6.4.2 AP1969 Rotary Head Part 1
6.4.3 AP1696 M2x 10 Cross Plate Screw 12
6.4.4 AP1970 Prism Assembly 1
6.4.5 AP1971 Locking Nut 1
6.4.6 AP1592 M3 x 4 Inner Hexagon
Tightening Screw
1
6.4.7 AP1972 12MM Bearing 2
6.4.8 AP1973 Big Gear Assembly 1
6.4.9 AP1449 M2.5x 6 Cross Plate Screw 4
6.4.10 AP1915 M2.5 Elastic Gasket 2
6.4.11 AP1974 Electric Motor 1
6.4.12 AP1975 #6 PCB 1
6.4.13 AP1976 Base Assembly 1
6.4.14 AP1977 Indicator 1
6.4.16 AP1978 #9 Connecting PCB 1
6.4.17 AP1979 M4 x 12 Inner Hex Column
Screw
1
6.4.18 AP1967 M4 Elastic Gasket 1
6.4.19 AP1980 Compression Spring 1
6.4.20 AP1981 Sensor Assembly 2
6.4.21 AP1982 Spacer 1
6.4.22 AP1983 Ball Gimbal Assembly 1
6.4.23 AP1984 M2.5 flat spacer 2

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40-6537 Service Manual
2.5 Base Assembly (AP1942)
1. Disassemble Cover (7-2) by removing 5 retaining screws (7-1)
2. Remove #10 Connecting PCB (7-3) by sliding it out of the guide
slot of the Bottom Seat Assembly (7-4).
3. Disassemble Bottom Seat Assembly (7-4) by desoldering the
wires of 2 Feeler Parts (7-5). Press out Feeler Parts as required.
3.0 Calibration
Calibration is a process that is used to correct for accuracy and/or functional errors above and beyond those stated in
published specifications. While Manual-leveling, Self-leveling, and Automatic-leveling (motor driven) devices have
different mechanisms that require calibration, there are similarities with optics that is consistent regardless of the
leveling mechanism. This section of the service manual discusses calibrations specific to the 40-6537. Each item
discussed is shown below.
3.1 Horizontal Mode Operation
3.1.1 Quantifying Accuracy Error
3.1.2 Characterize the type of error
3.1.2.1 Oblique Error
3.1.2.2 Taper Error
3.1.2.3 Wave Error
3.2 Vertical Mode Operation
3.3 Leveling Range Alarm Calibration
Item JLT Part # Description Qty
7.1 AP1690 ST2.9 x 10 Cross Plate Tapping
Screw
5
7.2 AP1985 Cover 1
7.3 AP1986 #10 Connecting PCB 1
7.4 AP1987 Bottom Seat Assembly 1
7.5 AP1988 Feeler Part 2

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40-6537 Service Manual
3.1. Horizontal Mode Operation
In this mode of operation, the instrument is self-leveling, where by a major factor of accuracy is how well the leveling
compensator is balanced. Different types of errors require different methods of calibration. These errors are easily characterized
by placing the instrument on a flat surface following the guidelines below, and running the instrument with the rotating head
continuously rotating 360°.
3.1.1. Quantifying Accuracy Error
Establish the test set-up shown in the following illustration and confirm that it meets the following requirements:
1) The debugging platform should be horizontal with a error less than 0.1°(6′);
2) The distance L from the center of the debugging clamp to the wall should be L≥10m;
3) The accuracy of the reference marking is no less than 0.05mm/m;
4) The adjacent-light ruler should be put within 0.3m (12”) of the instrument (the zero position of the ruler should be located at
the same height as that of the laser line at the emitting hole).
1. Place the instrument for test on the test stand (preconfigured from the illustration above) with handle facing the far target .
2. Power the laser and function in full rotation mode (head rotates 360°)
3. Note the errors in all four quadrants of the instrument as read on the far target (i.e. x axis A = 0° and B = 180°, y axis C = 90°
and 270°)
You should end up with 4 numbers
i. A (0°) = _____
ii. B (180°) = ______
iii. C (90°) = ______
iv. D (270°) = ______
4. Since all of the errors are referenced against “0” on the far target, essentially the largest number from the data collected (A – D)
/ the distance should be equal to or less than the published specification for the product. If not, characterize the error and
determine method of calibration as defined by section 4.1.2 of this document.
0
Laser line
Reference Line
(Known Height)
Flat Surface (Test Stand)
Far Target placed on wall at least 10m (33ft) from Test
Stand, where “0” corresponds to them same height as
“0” on the target next to the aperature of the instrument.
Accuracy (A) = Difference between laser line
height and reference line height, divided by the
distance that the laser is from the wall (L)
Distance (L) >10m (33ft)
Target
Instrument for test (laser spinning 36
0° rotation)
0
Near Target placed within 0.3m (12”) of
instrument. Note that “0” of the target
corresponds to the height of laser line at the
aperature of the instrument.

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40-6537 Service Manual
3.1.2. Characterize the type of error
Use the following rules to determine what to of accuracy error the instrument for test has, and reference the stated
section to adjust for it. Note that the unit my have a combination of different types of errors to adjust for, in which
case, multiple calibration must be performed.
A=0 & B=0 C=0 & D=0
Yes
Yes Section 2.1.2.1
Oblique Error
A and B <> 0 but
A + B = 0
No
No
A and B <> 0 but
A = B
No
Section 2.1.2.2
Taper Error
Yes
Yes
No
C and D <> 0 but
C
+
D
= 0
C and D <> 0 but
C
=
D
No
No
Yes
Yes
Yes
Yes
Accuracy is beyond
published specification
A and B <> 0 and
A + B <> 0
Section 2.1.2.1
Oblique Error
Section 2.1.2.2
Taper Error
C and D <> 0 and
C + D <> 0
Accuracy meets published
specification
1
No
No
1
Section 2.1.2.3
Wave Error
A = B <>C=D
No Yes

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40-6537 Service Manual
3.1.2.1. Oblique error
This type of error occurs when leveling compensator does not hang straight (as illustrated to the right),
i.e. is not properly balanced. When the laser spins, it actually rotates on a plain that is not level, i.e.
perfectly horizontal whose rotating axis is not plumb. So value A on the left target does not has the
same sign as that on the right target, like, A0°=+2, A180°= -2. A number of factors can cause this
situation to exist.
Normal use – Depending upon how careful the user is with the instrument, finely tuned adjustments can be altered by
very large changes in temperature, vibrations (due to handling and transportation)
Shock – The instrument was dropped and components of the leveling system (gimbal, compensator weight and shaft.,
screw adjustments) have either been damaged or came out of alignment. If defective components are present, they will
need to be repaired or replaced prior to the calibration procedures defined below being initiated.
Depending upon the magnitude of the error (±.5mm/ or 0.0005”/in), only fine adjustments need to be made, i.e. calibration via the
remote control. Larger errors (>.5mm/m or 0.0005”/in) require coarse adjustment to get close, then fine adjustment to bring the
unit within specification. Both adjustments are defined below
Fine Adjust - Calibration via The Remote Control
If the error is within the range of ±0.5mm/m, it only needs to make calibration with the aid of remote control. The details are as
follows:
Shield key
SLOPE TI LT
+X-X -Y
+Y
SLOPE key
SLOPE up/down key
Sleep key
TILT key
CALIBRATE
Confirm key of
self
-
calibration
Adjust key of
self-calibration
Direction key of
self
-
calibration
TILT LED
Power key
Slope key
Slope-direction LED
Power LED
Slope-mode LED
TILT key
Weak battery LED
TI LT
SLOPE
XY
SLOPE

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40-6537 Service Manual
SLOPE
SLOPE SLOPE
SLOPE
1. Enter self-calibration mode
Power off the instrument and direct the X-axis towards wall.
Press the key and key simultaneously. While continuing to hold the key, remove finger from
the key. While continuing to hold the key, observe the main display’s LED’s flash 3 time. Once this
happens, remove finger from the key and observe that the rotating head of the laser continuously rotates. The
laser is now in calibration mode.
2. X-axis calibration
Press the key one time and verify that the X-direction LED on the keypad of the 40-6537 flashes,
indicating that it has entered the self-calibration mode on the X-direction.
Press the key to adjust the laser beam up or down to coincide with the reference line.
3. Y-axis calibration
Rotate the 40-6537 90° so that the Y-axis is now facing the wall.
Press the key one time and verify that the Y-direction LED on the keypad of the 40-6537 flashes,
indicating that it has entered the self-calibration mode on the Y-direction.
Press the key to adjust the laser beam up or down to coincide with the reference line.
4. Self-calibration confirmation
Press the key after finishing self calibration on both the X and Y axis and verify that the Self Calibration LED
extinguishes. The instrument will exit the self-calibration mode automatically after finishing self-calibration.
Power off the unit to store the calibration values into the 40-6537’s memory.
Repower the 40-6537 and confirm the units accuracy. Repeat procedure as required.
SLOPE
XY
SLOPE
XY

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40-6537 Service Manual
Coarse Adjust - Calibration via Internal Leveling Sensors
If the error is more than ±0.5mm/m, it will need to make calibration by adjusting the sensor. The details are as follows:
Fixture Setup (See Above)
1. Fix a square reflected prism on the debugging platform, and affix a label paper that having a light-emitting
aperture in center on the prism (the diameter of the aperture is about 1mm). Put an auto-leveling rotating laser that
having plumb-up point on the platform. Power on the unit and the plumb-up point will pass through the prism and
the light-emitting aperture of the label paper, and then to reflect on the wall. Take the center of the reflected laser
point on the wall as a point A.
2. Turn the unit by 90°, and take the center of the laser spot on the wall as points B, C, D in turn. The center of
internally tangent circle of these four points A, B, C, D is used as the reference point.
Core Module/Leveling Sensor Calibration
1. Fix the core part on the special clamp. By supplying the laser source with a power of DC 3V, the laser spot will
pass through the aperture on the laser paper and to reflect on the wall. Adjust the three leveling knob on the
tribrach base (shown above), in order to make the center of the reflected laser spot coincident with the reference
point.
2. Fix the sensors of X & Y direction to the proper positions on the core part using 2 crosshead plate screw M2×5.
3. Adjust the position of the sensors by connecting a specially designed instrument developed for sensor levelling
position, and adjusting until the signal shows that sensor is level, i.e. the upper & lower arrows occupy no more
than one grid. And then tighten the screws on leveling sensor, securing it to the core module.
4. After the sensors of both X & Y directions have been calibrated, loc-tight the heads of the tightening screws to the
sensors so that they cannot come loose.
Crosshead plate screw M2
×
5 (4pcs)
Display of the adjusting fixture for sensor
Connecting plate
Adjustable tribrach base
Sensor module (2pcs)
Display of the well-adjusted sensor
Reference point Reflected prism
Label paper with a 1mm round aperture in center
Wall
Fixture used for adjusting the sensor
10m

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3.1.2.2 Taper Error
Taper error results when the prism base module (discussed in section 2.4, item 6.4.4) does
not reflect the laser light exactly 90° (i.e. non-perpendicularity between the rotating line
and the rotating axis). The end result is a laser rotating surface that is not a plane, but a
tapered one as shown in the figure to the right. The value A in the left target shares the
same symbol as the one in the right target during the check, that is, A0°=+2 and A180°= +2. The error is removed by adjusting the
optical wedge of the laser output window to make the rotating laser beam and rotating axis plumb beam. The details are listed as
follows:
a. Remove the top cover as discussed in section 1 of this document
b. Screw the wedge out of its base with special spanner as shown in the
figure to the right.
c. Adjust the laser to the zero position of the target.
d. Loc-tight adjust after it has been set.
Note: Only one direction (X or Y) is necessary for the adjustment.
Taper error
Optical wedge

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40-6537 Service Manual
3.1.2.3 Wave Error
This error occurs when the rotating laser surface is not a plane, but a turn up one as
shown in the figure to the right. The rotating beam projected on the wall is crooked,
similar to waviness, which is caused by the unbalance of rotating head. The value A
checked in the X-direction deviates upwards while the one in the Y-direction
downwards, or the value A in the Y-direction upwards while the one in the X-direction downwards. Meanwhile, you can see the
laser point above the head is mobile and its orbit is inclined to be a circle.
The error can be removed by adjusting the balance block of the Rotating head as follows:
a. Remove the top cover as discussed in section 1 of this document.
b. Regulate the adjusting screws on the four balance block as shown in the figure to the right, until the laser point above
the head becomes stable, namely, the laser point projected on the ceiling being a stable one.
1) As shown in the figure below, put the table vice on the debugging platform;
2) Fix the core part without prism on the adjustment fixture, and Install the adjustment fixture on the table vice, to make the
laser spot towards the wall;
3) Turn the core part, to make the laser revolve around the rotary axis. Adjust the 4pcs of adjustment crews which are used for
fixing the laser indicator, in order to make the diameter of the laser spot circle no more than 1cm;
4) Spread the screw and laser source part with shellac;
Wave error
Adjusting fixture
Table vice
Core part
Wall
φ
1cm
10m

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40-6537 Service Manual
3.2. Vertical Mode Operation
In this mode of operation, the rotating laser surface is a plumb plane, while the laser line projected from the top is in projecting
horizontal. While in this mode, the instrument is manually level, meaning that accuracy is a function of how accurately the vial
is calibrated. The 40-6537 is not designed for Vertical Mode Operation.
3.3. Alarm Calibration
The alarm function is made up of 3 components, the 2 alarm PCB’s (7-15-17, 7-14-13) and the buzzer (10-3). Calibrating it is a
matter of centering the contact ring of 7-14-13 to the spring post of 7-15-17. When the spring post makes contact with the
contact ring of 7-14-13, the buzzer (10-3) sounds. Centering the post between the ring offers equal angular alarming in all
directions. Adjustments are made as follows:
a. Remove the Upper housing assembly as shown in section 2.1.
b. Locate the adjustment screws 6-10 (reference section 2.3).
c. Loosen the adjustment screws 6-11and 6-12 to manually center
the contact ring to the spring post.
d. Tighten the adjustment screws and reassemble the upper
housing assembly to the base assembly.
4.0. Electrical Connections
Adjustment screw (2pcs)
8# alarm circuit board part
MOTOR BELL
LD
POW
FFC连接线
FFC连接线
4#
1# 5#
FFC连接线
2# 3#
9#
6#
XY
光源
旋转电机
11#
+
X传感器
Y传感器
Y轴电机 X轴电机
3V
蜂鸣器
12#
10#
8#

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5.0. Troubleshooting Guide
No. Symptom Cause Corrective Action
Battery case is loose Change battery box
1# control board is defective Change 1# control board
Battery is low Charge/Change Battery
Power switch is defective Change Power Switch
Cabling between PCB #1, PCB #3, and
PCB #5 is loose/defective Change/repair cabling
1 Unit doesn’t turn on
Cabling between PCB #1 and PCB #10 is
loose/defective Change/repair cabling
PCB #1 is Defective Repair/Replace PCB
PCB #11 is Defective Repair/Replace PCB
Cabling between PCB #1, PCB #3, and
PCB #5 is loose/defective Change/repair cabling
2Remote control does not
work
Cabling between PCB #3 and PCB #11 is
loose/defective Change/repair cabling
Cabling from #12 PCB is defective Change/repair cabling
3Alarm Sounds when power
comes on. Ball switch from #12 PCB is defective Repair/Replace PCB /Switch
Cabling between PCB #1, PCB #3, and
PCB #5 is loose/defective Change/repair cabling
PCB #1 is defective Repair/Replace PCB
PCB #2 is defective Repair/Replace PCB
4Indicators don’t light upon
key press
PCB #3 is defective Repair/Replace PCB
PCB #6 is defective Repair/Replace PCB
Cabling from PCB #6 is defective Change/repair cabling
5
Incorrect Quadrant
Shield/incorrect rotating
speed Reflective Plane is Dirty Clean Reflective Plane
Cabling between PCB #5 and PCB #12 is
loose/defective Change/repair cabling
Cabling between PCB #4 and PCB #81 is
loose/defective Change/repair cabling
6No Alarm when tilted
beyond tolerance
Cabling between PCB #1 and PCB #9 is
loose/defective Change/repair cabling
Buzzer is defective Repair/Replace Buzzer
7alarm when tilted beyond
tolerance but no sound Cabling from Buzzer is defective Change/repair cabling
Cabling to laser is defective Change/repair cabling
8 Unit powers, but no laser Laser is defective Repair/Replace Laser
Cabling between PCB #1, PCB #4, and
PCB #5 is loose/defective Change/repair cabling
9 Unit doesn’t auto level
Core Spring is loose/spring is tightened Adjust spring