JK-T781E

series

technical parameters and models

Model

Purpos

Buttonhole length

Stitch width

Cutter length

Speed

Needle stroke

Presser foot height

Needle

Refueling mode

Sewing thickness

Needle count

JK-T781E JK-T782E JK-T783E

(Textile, chemical fiber fabric )buttonhole`s sewing lock

22mm 33mm 40mm

JK-T781EK

Knitting

2.5~4mm 2.5~5mm 2.5~5mm

22mm

2.5~4mm

6.4~19mm

(1/4”~3/4”)

6.4~25.4mm

(1/4”~1”)

6.4~31.7mm

(1/4”~1 1/4”)

100~3600rpm/min

34.6mm

10mm

DP × 5 （ #11~#14 ）

6.4~19mm

(1/4”~3/4”)

Automatic oiling

4mm

Factory equipped with 4 unitsG(225,83) J(190,100) L(170,110)

N(152,123)

Market has 8 units 54针 ~345 针

1.2 adjust needle and hook

First way：see the no. of 2 in the first picture, put the ruler like this between the Needle plate and needle bar，move the position of needle bar until the distance between needle bar and the ruler is 0. Adjust the hook to make the tip of the hook from the upper end of the pinhole 1.6 ~ 1.8mm, tighten the screw of Rotary hooks to make that the distance between two Tips of the hook is about 0.05 mm.

1.6~1.8mm

0.05mm ruler, this part 14.2mm

requirement for catching thread

2.1

、

adjust the needle bar height

Second way:（observe the hook)，Install the needle to make the needle in the middle of the pinhole, move the needle bar to the lowest point, observe and make the upper edge of the pinhole not exceed the needle plate.

lowest point,of the needle needle plate

Front panel of neele plate the middle of the pinhole

2.2

、

adjust needle and hook

Second way: 1、 Turn the handle，until the the pallet moves to the right baseline，

Turn the handwheel until the needle moves to the right baseline，during the period of returning of the needle bar, adjust the Rotary tip util hooking above the pinhole，at the the lowest plat.

2、Adjust the rotary hook positioning screw, util hook tip close to the needle, but not hit the needle (zero distance).3、pls. note when the hook catchs thread, the rotary hook needle plate must be close to the needle, but not squeezed(zero distance). hooking above the pinhole the needle moves to the right baseline requirement for catching thread hook tip close to the needle

3.0

、

adjust buttonhole width and stitching reference position

The movement of the needle is based on the right side of the needle swing. When adjusting, please follow the following steps:

1、Baseline width adjustment: Turn screw 1 and align the baseline pointer to the desired scale on the scale plate.

2 、 Reinforce sewing width adjustment ： Tighten screw 2 to align the reinforcement pointer to the baseline pointer.3

、 Right baseline position: twist screw 3, adjust the cutter to cut the screws when the right baseline is not cut.4

、 Left position of the baseline: When screwing the screw 4 so that the blade does not have a left baseline, tighten the screw.

Baseline pointer

Scale plate screw 1 screw 4

Reinforce pointer screw 3 screw 2

4.0 adjust position of feeding control panel when work finished

◆ If the control plate position is not correct, whenever you change the sewing size, the knife will malfunction, the position of the presser foot will change, resulting in broken needle, broken thread.

◆adjustment method: when stopping,make the scale line of plate align the middle position of the roller pin screw. If the position is not correct, move the part A of the right pic. to reaze this .

大盘刻线

Scale line of plate control plate

18.0

：

Adjustment of the button hole length

Standard ： This adjustment is same as 781D serie.

Method ：

1. Pull out the part, put up the canning.

：

（ The number should be same as length of cutter) Then tighten the screw 。

Feeding Crank

Loose screw

Pointer 781E Machine mode and Number Comparison table

Mode 781E 782E 783E 781EK

Number on dial

1/2 1 5/4 1/2

Notice ： After change the number on dial, then should change the presser foot similar as the length of button hole.

19.0

： Adjustment of the position of lower line fixed knife

Adjustment stardard: the distance between fixed knife and needle plate hole is 0.3-0.5mm.

Adjustment influence: if the distance between the fixed knife and the needle plate hole is too close, the thread breakage will happen when you sew. fixed knife fasten screw

Adjustment method:

1.Lose the fixed knife fasten screw.

2. Adjust fixed knife, make the distance between the fixed knife and the needle plate hole to 0.3-0.5mm and then fasten the screw. fixed knife

29.0

：

The sensor chip of automatic foot-lift position adjustment

Adjustment standard: When the machine is in the parked position (the presser foot is in the decentralized state), the motor will automatically find the zero position, so that the mechanical lock between the starting plate and the movement pin left 3mm gap.

Adjustment methods ：

1. Loosen the setscrews and adjust the sensor chip up and down relative to the sensor. （ Up to adjust sensor chip, the gap becomes larger after booting to find the zero position, down to adjust the gap smaller.)

2.

Re-boot to find zero position, verify the mechanical lock between the starting plate and the movement pin left 3mm gap.

Larger

Sports pin

Sensor Smaller

Stamp mark

Sensor chip

The sensor chip is aligned with up-side of the stamp mark of sensor

3mm Gap

31.0

：

Adjustment and functions of feeding sensor

◆ The main function of feeding sensor is:prevent foot lifting during sewing, the sensor lamp goes out when entering the sewing state ， press , can not lift the foot ， when stop sewing, the sensor lamp lights up and presses presser , lift the presser foot

◆ Easy to adjust the presser foot up and down during maintain

Adjustment method ； Loosen the set screws, adjust the sensor up and down, make sure that the distance between sensor and sensor magnet is about 1.5mm, and could be lit up when stop sensor magnet set screw set screws

三、

Parameters and fault codes

1、Operation button

Enter and determine the stored content value

Enter the parameter area function key

Set the value increment / parameter increment

Set the value decrement / parameter decrement

Enter the parameter content value, any changes of the value, need to press the key to save confirmation.

1. In normal boot mode, press the key to enter the user parameter mode

2. Press and hold the key to enter the technician parameter mode

1. In the parameter selection area, as the key to increase the parameter

2. In the parameter contents area, as the key to increase the value

1. In the parameter selection area, as the key to decrease the parameter

2. In the parameter contents area, as the key to decrease the value

2 、 LED display script and actual script comparison table

Digital script part ：

Actual value ：

LCD ：

3 、 Display mode of the LCD screen

English script part ：

English alphabet ：

LCD ：

English alphabet ：

LCD ：

English alphabet ：

LCD ：

4 、 Factory reset

Press the up and down key and at the same time boot the machine up, it will show P11.

Press enter key to save it

Press F key and reboot

5、Enter user mode and modify & save(1-10)

In normal case, press F to get into user parameter mode.

Press up and down key to change parameter items.

Press enter key to get the value of this parameter.

Press up and down key to modify the parameter value.

Press enter key to save the value

Press F key to get out of this mode.

6、Enter technician mode * （ 11-25 ）

Press F key and at the same time boot the machine up

Press up and down key to change parameter items.

Press enter key to get the value of this parameter.

Press up and down key to modify the parameter value.

Press enter key to save the value

Press F key to get out of this mode.

7 、 System officer mode-limited to item （ 26-27 ）

Press F and enter key and at the same time boot the machine up

Press up key to find

P26 (speed limit) and the press ENTER to get the value.

Press up and down key to modify the parameter value and then press enter to save.

Press F key to get out of this mode.

8、Manual up positioning adjustment

Press the up and down key and at the same time boot the machine up

Press up key to find

P27 and the press ENTER to get into it.

Move the hand wheel to adjust and press enter key to save.

Press F key to get out of this mode.

9、user parameters

item description range Initial note value

P01 Max speed （ rpm ） 10 ～ 360 300 Sewing speed （ actual speed=display number

P02 Start sewing speed

（ rpm ）

*10 ）

20 ～ 360 130 Start sewing speed （ actual speed=display number*10 ） for 781E, it doesn’t work

P03 Cutter movement speed

P04 Speed limit for 1 st stitch

P05 Speed limit for 2 nd stitch

P06 Speed limit for 3 rd stitch

P07 Speed limit for 4 th stitch

P08 Speed limit for 5 th stitch （ reserved ）

P10 Stitches required

10- 100

10

10

10

10

10

0 - 5 during the cutting.

～

～

～

～

～

360

360

360

360

360

P09 Presser foot protection time （ s ）

1 - 120

55

80

80

3

200

250

200

8

The rotation of head during the cutting speed=display number*10

（

（

（

（

（

） actual speed=display number*10 actual speed=display number*10 actual speed=display number*10 actual speed=display number*10 actual speed=display number*10

）

）

）

）

）

（ actual

Presser foot will drop after exceeding the continual lifting time set. (Only for

781D）

Stitches required during the cutting.

Coordinated with cutter speed.

item

P16

P22

Protected stitches

P17

P18

Find the up position automatically after booting

Up positioning adjustment

P19 Test working time

P20 Test stop time

P21 A test

B test

P23 C test

P24 Head protection switch

P25

Mechanical lock protection switch

P26 Speed limit

P28

The highest presser foot height

P29 description

Presser middle position range

1 - 990

0 - 1

40 - 180

1 - 250

1 - 250

0 - 1

0 - 1

110

20

20

0

0

Initial value

400

1 note

How many stitched protected if the big board senses nothing

1：Find the up position automatically after booting

0：function closed

Up positioning adjustment, value decreases means stop in advance by 2mm and vice versa

In C test, setting working time.

In C test, setting stop time.

In A test, continual working test with speed P01

In B test, full functional test with speed P01

0 - 1

0 - 1

0 - 1

10~360

0 - 400

0 - 400

0

1

1

300

250

00

In C test, no positioning working with speed P01

0：function closed

1：function

0：function closed

1：function

Speed limit（ actual speed=display number*10 ）

Adjust the stepper motor angle when it’s in highest presser foot height

Adjust the stepper motor angle when it’s in presser middle position

11、Error code

Error code

E1

E3

E6

E7

E9

E11

Content Solution

1) Power module error code

2)Abnormal overcurrent and overvoltage

Stepper motor communication abnormal

Stepper motor senses abnormal a.

Loose contact of engine plug b.

Position signal abnormal c. Head is blocked d .

Fabric is too heavy . e. module drive efforts abnormal

Module driver efforts and head efforts are both closed. waiting for restart （ check power board ） not frequent

Check the communication line between stepper motor drive board and main board.

1.

Check if stepper motor sensor (optoelectronic switch) is ok

2.

Check if stepper motor’s mechanical structure is right

Module driver efforts and head efforts are both closed. waiting for restart （ check machine head, positioner, engine, module drive)

）

Positioning signal abnormal Check up and down positioning signal and belt pulley

Find the up position automatically after booting. But positioner inserts to

Engine doesn’t work.(Check positioner ） control box, needle signal cannot be outputted.

12、Error code

E12 Power on and no positioner inserted

E13

E14

E15

Power module overheating protection

Encoder signal fault

Power module abnormal overcurrent production

Automatically working in no-positioner mode, and cutting thread, tangent, up positioning and all fixed needle sewing pattern sewing functions have no effect. The motor can work normally.

（ check positioner ）

Check the power module and cooling fin is good contact

Check whether the encoder signal is right or change the encoder

Module driver efforts and head efforts are both closed. waiting for restart （ check power board function ）

E17 Head protection switch is not in its position

Check the head position and the switch.

E18 Mechanical lock protect error code

E19 Big board protect error code

Check mechanical lock position and the switch.

Check the big board position and the switch.