Pfaff select 1520 User manual

Service Manual
1st Release August 2001

1
Contents 1
Foreword 3
Notes on the sewing machine in relation to environment, handling, cleaning and safety 5
Specifications off PFAFF machines 6
Removing the housing covers 8
Adjustment instructions
Feeding system
1. Adjustment of toothed belt tension 13
2. Adjustment of feed dog in sideways direction on Pfaff 1520 14
3. Adjustment of feed dog in sideways direction on Pfaff 1530-1540 16
4. Adjustment of feed dog height 18
5. Adjustment of presser bar height on Pfaff 1520 19
6. Adjustment of presser bar height on Pfaff 1530-1540 20
7. Adjustment of top feed foot in sewing direction 22
8. Adjustment of top feed foot height 24
9. Adjustment of feed regulator cranks on Pfaff 1520 / 1530 26
10. Adjustment of feed regulator cranks on Pfaff 1540 27
11. Zero point adjustment of stitch length regulator 28
12. Timing of feed motion 30
Automatic utility-stitch unit
13. Replacing the automatic module on Pfaff 1520 - 1530 32
14. Adjustment of the locking disk 34
15. Replacing the zigzag-stitch unit on Pfaff 1520 - 1530 35
16. Basic position of setting eccentric for the sideways needle position 36
17. Adjustment of needle penetration in needle plate slot 37
18. Adjustment of the sideways movement of the needle bar 38
19. Adjustment of the stop for the left needle position 40
20. Adjustment of the feed reversing bar 42
21. Replacing the utility-stitch unit on Pfaff 1540 44
22. Adjustment of the gears in relation to each other 46
23. Replacing the zigzag-stitch unit on Pfaff 1540 47
24. Basic position of setting eccentric for the sideways needle position on Pfaff 1540 48
25. Adjustment of needle penetration in needle plate slot on Pfaff 1540 49
26. Adjustment of the sideways movement of the needle bar on Pfaff 1540 50
27. Adjustment of zigzag stitch penetration in needle plate slot on Pfaff 1540 52
28. Adjustment of the stop for the left needle position on Pfaff 1540 53
Stitch forming parts (sewing hook)
29. Adjustment of needle clearance in needle slot in sewing direction 56
30. Adjustment of hook-to-needle clearance 58
30a. Adjustment of bevel gears 59
31. Sewing hook timing 60
32. Adjustment of needle bar height 62
33. Adjustment of bobbin case position finger 63
Page

2
Stitching off
34. Adjustment of needle threader 64
35. Adjustment of bobbin winder stop 66
36. Adjustment of bobbin thread tension 67
37. Adjustment of needle thread tension 68
38. Adjustment of thread check spring stroke 70
39. Adjustment of equal stitch length for left and right buttonhole seams 72
40. Adjustment of equal forward and reverse stitch length 73
(for forward and reverse controlled utility stitches)
41. Making up a sewing sample 74
Repair Instructions
42. Removing and fitting the needle thread tension 75
43. Changing the pressure spring in the handwheel release 76
44. Removing and fitting the sewing hook 78
45. Cleaning and oiling the machine 78
46. Changing the toothed belt 80
47. Adjusting the arm shaft crank 82
48. Changing the bevel gears 84
49. Changing the motor 88
50. Changing the motor circuit board on motor types UUS 390 and UUS 393 90
51. Changing the carbon brushes on motor types UUS 390 and UUS 393 91
52. Changing the motor pinion 92
53. Changing the motor toothed belt 93
54. Changing the circuit board in foot control AE 010 94
55. Changing the mains connections in foot control AE 010 95
Safety test
56. Electrical safety test 96
57. Electrical safety test with ABB Metrawatt M 5013 96
58. Simulated leakage current measurements of complete motors with ABB Metrawatt M 5013 99
59. Measures required in case of incorrect readings 99

3
Foreword
The purpose of this service manual is to assist you in quick and correct repair of the machines.
Adjustments should only be made if the settings deviate from the requirements described in this manual.
When checking or adjusting a machine, always proceed in the order of the worksteps prescribed.
For easier reference, each workstep is identified by a number. Different operational procedures are indica-
ted by a circle or a square.
The indications "left", "right", "top", "bottom", "front" and "back" always refer to the upright machine with
the controls facing the operator.
When assembling dismantled machines, adjust the machine to approximately the right settings.This facili-
tates the subsequent fine adjustments.
Unless otherwise specified, the handwheel must always be turned forward.
When carrying out maintenance work on live parts or in their proximity, the machine is to be separated
from the power supply by disconnecting the lead cord from the electrical socket.
An electrical safety test must be carried out after all repair work, even if the repair work is of a mechanical
nature.
The required electrical tests for the appliances are laid down in the current EU regulations, EEC direc-
tives, and the EMC-law (Standard EN 60335-1/A: 96 = ICE 335-1: 91/A1:94, mod).
It is obligatory to perform a safety test in accordance with VDE 0701-1 after repair, modification and
testing of electrical appliances.
Outside Germany there are similar regulations in force which are largely identical with the requirements of
VDE 0701.
It is therefore necessary to consult a specialist when carrying out repairs on electrical appliances.

4
For the proper adjustment of the machine, the following gauges and tools are required:
zNeedle rise gauge: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .00-870136-01
zNeedle rise clamp: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .00-870137-01
zSpacer: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63-102600-18
zAdjustment gauge for the bobbin case holder: . . . . . . . . . . . . . . . . . . .00-880133-01
zPresser foot gauge: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63-114690-39
zRing-shaped open-end spanner 5.5 mm . . . . . . . . . . . . . . . . . . . . . . .43-111010-04
zTorx screwdriver TX 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-40
zTorx screwdriver TX 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-44
zTorx screwdriver TX 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-45
zTorx screwdriver TX 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-46
zTorx screwdriver TX 25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-47
zTorx offset screwdriver TX 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-434008-74
zCirclip fitting tool 2.3 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-20
zCirclip fitting tool 3.2 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-30
zCirclip fitting tool 4.0 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-40
zCirclip fitting tool 5.0 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-50
zCirclip fitting tool 6.0 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-60
zCirclip fitting tool 10.0 short . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437003-86
zSpring hook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .07-437006-00
Subject to design and dimensional modifications.

5
Notes on the sewing machine in relation to environment, handling,
cleaning and safety
Environment:
The recommended operating ranges are as follows:
Ambient temperature -10°C to 40°C (50° to 104°F)
Air humidity 20 % to 80 %
This machine is a high-quality electro-mechanical device. It is designed for household purposes and
should always be supervised when in use.
Make sure that it is not subjected to: dust, severe dampness, direct sunlight, static electricity, heat-produ-
cing objects, corrosive chemicals or liquids.
To ensure adequate ventilation the machine should be placed unobstructed on a firm, even surface.
Handling:
Always protect the machine from damage caused by hitting or dropping.
Cleaning:
To clean the housing, use a dry, clean, soft, lint free cloth.To remove particularly persistent dirt, use a
soft cloth with a neutral cleansing agent for plastic materials.
Please note!
Do not use any insecticides or chemical products such as petrol (gas) or liquid chemicals to clean the
housing.
Safety:
1. The machine must be put into operation according to the indications on the specification plate.
2. Do not place any objects in the openings on the machine.
3. Do not use the sewing machine if:
- there is visible damage,
- its function is defective,
- it is wet, e.g. with condensation.
4. Do not pull the mains plug out of the socket by its cord.
5. If this appliance is used for another purpose than that intended, or if it is wrongly operated, we cannot
accept any liability for any damage caused.
6. To avoid the risk of electric shock, do not open the machine.There are no parts inside the machine
which the user can repair.This is solely the responsibility of our qualified service staff.
7. Be sure to use only original PFAFF parts.

6
Specifications of PFAFF machines
PFAFF 1540
Electronic free-arm utility stitch machine with 40 sewing programs (push buttons).
A straight stitch program with 15 needle positions.
A zigzag program with 15 needle positions.
A buttonhole program with adjustable width.
37 utility stitches.
High-ohm foot control (cold) with torque raising.
Dual fabric feed. Needle threader.
PFAFF 1530
Electronic free-arm utility stitch machine with 15 sewing programs (program dial).
A straight stitch program with 15 needle positions.
A zigzag program with 15 needle positions.
A buttonhole program with adjustable width.
12 utility stitches.
High-ohm foot control (cold) with torque raising.
Dual fabric feed.
PFAFF 1520
Electronic free-arm utility stitch machine with 15 sewing programs (program dial).
A straight stitch program with 15 needle positions.
A zigzag program with 15 needle positions.
A buttonhole program with adjustable width.
12 utility stitches.
High-ohm foot control (cold) with torque raising.
Detailed specifications of the machines
zElectronic free-arm utility stitch machine
zDirectly controlled automatic utility-stitch unit, step-down ratio 6:1 (1540)
zProgram selection by means of a program dial (1520/1530)
zUtility stitch width 5.5 mm
zStitch length from 0 to 6 mm
zReverse stitch length from 0 to 3 mm
zHigh-ohm foot control (cold)
zFM radio and TV screened, approval marking, suppression degree B
zSafety class II with GS test marking
zMaster switch for motor.
zGlare-free built-in sewing lamp 230V or 120V 15 W
zPendulum-type needle bar frame
zTransmission of drive from arm shaft to lower shaft by toothed belt, transmission ratio 1:1
zPower input rating: 90 W when sewing at 950 r.p.m.; 40W when stationary

7
zMaintenance-free PFAFF transverse double-rotating hook
zLink take-up lever
zLinkage-type feed regulator
zDual fabric feed
zDisengageable feed dog
zNeedle threader
zDrive from motor to handwheel by flat-toothed belt
z60-1000 stitches per minute
zSintered metal bearings
zOil for sintered metal bearings: BP Energol HLP 46 or HLP 80 No. 28-036550-09
zOil for sewing hook No. 91-129452-91
zClear workspace: 175, 114, 205 mm
zMachine height: 280 mm
zBaseplate dimensions: 390, 155 mm
zFree arm dimensions: 80, 49, 200 mm
zHousing material: lightweight metal
zWeight of sewing head: approx. 8 kg
zNeedle system 130/705 H
Additional needle system classifications:
Twin needle Suffix = Zwi
Wing needle Suffix = Wing
Twin hem stitching needle Suffix = Zwi-Ho
Top stitch needle Suffix = N
Stretch needle Suffix = PS
Jeans needle Suffix = J
Possible needle points:
Small ball point Suffix = SES
Medium ball point Suffix = SUK
Large ball point Suffix = SKF
Very pointed round point Suffix = J
Leather point right hand Suffix = LR
Specifications and versions of built-in motors in the PFAFF 1520-1540
Type UUS 390 220-240V 50/60Hz 4500 r.p.m.
No. 902-1039-001 27W
Radioscreened according to EN 55014 Safety class II
Type UUS 393 110-120V 50/60Hz 4500 r.p.m.
No. 902-1039-003 27W
Radioscreened according to EN 55014 Safety class II

8
Removing the housing covers
Note:
Before adjusting or repairing the machine, make sure to remove the housing covers as described
in this manual.
zDisconnect the machine's main plug.
zRemove needle and presser foot.
zRemove detachable work support.
zRemove top cover.
zSwitch on bobbin winder.
zRemove the two Torx screws of the housing insert..
zRemove housing insert.
zLay the machine on its back and remove the four fastening screws of the baseplate.
zRemove baseplate.
zRemove the two fastening screws 1 of free-arm cover (fig. 1).
zPull the left-hand side of the free-arm cover a little bit downwards and remove it towards the left.
zRemove needle plate.
zRemove the two fastening screws 2 of the upper free-arm cover (fig. 2).
zLoosen fastening screw 3 of free-arm cover.
zRemove free-arm cover.

9
zLoosen the fastening screws 4, 5, 6 and 7 of the rear housing shell (fig. 3 and 4).
zLoosen the snap connections by pressing with your thumb on the spots marked with arrows on
the inner surface of the arm (fig. 5).
zRemove the rear housing shell.
zRemove motor cover.

10
zLoosen the fastening screws 8, 9, and 10 of the front housing shell (fig. 5 and 6).
zRemove fastening screws 10 and 11.

11
zRemove fastening screw 12 (fig. 7).
zSwitch on the top key row of the utility stitch unit.
zCarefully remove the front housing shell by lifting it off.
The assembly must be carried out in reverse order.

12
Notes:

13
Feeding system
1. Adjustment of the toothed belt tension
Requirement:
The toothed belt must be so taut that the sewing hook has no play in its direction of rotation.
However, it must be possible to turn the machine easily.
Adjustment:
zLoosen screw 1 (fig. 1)
zRe-position tensioning roller 2 with a screwdriver as required.
zTighten screw 1.
Check:
zCheck adjustment according to the "Requirement".
zPress lightly against the middle of the toothed belt (250 g).
The toothed belt should move forward by some 1 to 3 mm.

14
2. Adjustment of feed dog in sideways direction on Pfaff 1520
Requirement:
The left and right clearance of the feed dog in the feed slot must be the same (fig. 2).
Check:
Carry out a visual check of the feed dog position.
Adjustment:
zLoosen the two screws 3 and 4 (fig. 2a).
zLoosen screw 5.
zDetach spring 6.
zRe-position feed-dog driving shaft 7 with the two cylindrical pins 8 and 9 sideways until the feed dog is
centered in the feed slot.
zFirmly tighten the two screws 3 and 4.
zPush bolt 11 against connecting bar 10.
zFirmly tighten screw 5.
zRe-attach spring 6.
Cross-check:
The feed dog must be exactly in the center of the feed slot.The feed driving shaft must not bind nor have
any play.

15

16
3. Adjustment of feed dog in sideways direction on Pfaff 1530-1540
Requirement:
The left and right clearance of the feed dog in the feed slot must be the same (fig. 3).
Check:
Carry out a visual check of the feed dog position.
Adjustment:
zLay the machine on its back.
zLoosen screw 12 (fig. 4).
zRemove bolt 13 to the right.
zLoosen screw 5.
zRemove circlip 14.
zRemove bolt 11.
zLoosen both screws 3 and 4.
zRe-position feed-dog driving shaft 7 with the two cylindrical pins 8 and 9 sideways until the feed dog is
centered in the feed slot.
zFirmly tighten the two screws 3 and 4.
zDetach spring 6.
zRemove the needle plate.
zPull the feed dog forward with one finger and release.
zThe complete feed-dog driving shaft 7 must slide lightly back.
zLoosen screw 15 (fig. 5).
zMove the top feed lever forwards and backwards.
zThe top feed should move freely without any difficulty (if necessary, remove cause of binding).
zFit bolt 13 with the washer located to the left of pull-rod 18, and ensure that it is free from play (fig. 4).
zMove the complete top feed lever forwards and backwards.
zMake sure that both top and bottom feed move smoothly and without any difficulty.
zTighten screw 12 and check once again for ease of operation.
zMove crank pin 16 with pull-rod 17 to the side in such a way that both top and bottom feed can move
easily.
zTighten screw 15 and check once again for ease of operation.
zFit bolt 11.
zInsert circlip 14.
zPush bolt 11 against connecting bar 10.
zTighten screw 5.
zRe-attach spring 6.
Cross-check:
The feed dog must be exactly in the center of the feed slot.
Both top and bottom feed must not bind nor have any play.

17

18
4. Adjustment of feed dog height
Requirement:
At the highest working position of the feed dog, the tips of the feed dog teeth must protrude above the
needle plate surface by 0.9 mm (fig. 6).
Check:
zRemove the needle.
zRemove the presser foot.
zSet the maximum stitch length.
zPlace bridge gauge (63-112120-08) over the feed dog onto the needle plate.
zTurn the handwheel until the feed dog has reached its highest working position.
zCarry out a visual check.
zThe feed dog must not touch the gauge, but must clear it by 0.1 mm.
Adjustment:
zLoosen screw 19 by just 1/8 of a turn (fig 7).
zTurn eccentric stud 20 until the eccentric is facing the rear part of the housing (basic position)
zTurn the eccentric stud to the left until the feed dog height is properly set.
zTighten screw 19.
Cross-check
zTurn the handwheel and check the feed dog height at its highest working position.
zMake sure that the feed-dog lowering mechanism neither binds nor hits against anything when the
handwheel is turned.
zLower feed dog and check the function.