ESAB A2-A6 PEK Service Manual

Service manual

0740 801 028 GB 20171110

Valid for: serial no. 921-, 943-, 049-, 327-, 628-xxx-xxxx

A2, A6 PEK Control Unit

TABLE OF CONTENTS

0740 801 028 © ESAB AB 2017

READ THIS FIRST.................................................................................... 4

INTRODUCTION....................................................................................... 5

WIRING DIAGRAM ................................................................................... 7

Component description ......................................................................... 7

A2, A6 PEK Control Unit, Serial no. 921-, 943-, 049-, 327-xxx-xxxx ... 8

A2, A6 PEK Control Unit, Serial no. 628-xxx-xxxx .............................. 10

TECHNICAL DATA ................................................................................... 12

INSTALLATION AND CONNECTIONS .................................................... 13

External connections ............................................................................. 13

Internal connections .............................................................................. 15

DESCRIPTION OF OPERATION.............................................................. 23

1 MMC unit .............................................................................................. 23

Circuit board identity............................................................................. 23

1AP1:1 Power supply and CAN bus..................................................... 24

CAN bus & termination...................................................................... 26

1AP1:2 Display control ......................................................................... 27

1AP1:3 Pushbutton monitoring............................................................. 27

Buzzer ............................................................................................... 28

1AP1:4 USB memory ........................................................................... 28

1AP1:5 Encoder monitoring ................................................................. 29

1AP1:6 Ethernet interface, from serial no. 628-xxx-xxxx ..................... 30

1AP1:7 USB-host B (internal), from serial no. 628-xxx-xxxx................ 31

1AP1 Component positions.................................................................. 32

26 Motor control & motor drive ............................................................. 34

26AP1 Motor control .............................................................................. 34

Circuit board identity............................................................................. 34

26AP1:1 Power supply ......................................................................... 34

26AP1:2 CAN bus & termination .......................................................... 35

26AP1:3 Encoder for wire feed motor .................................................. 36

26AP1:4 Encoder for travel motor ........................................................ 37

26AP1:5 Travel limit switches............................................................... 37

26AP1:6 Laser lamp supply ................................................................. 38

26AP1:7 External Start/Stop switch ..................................................... 38

26AP1 Component positions................................................................ 39

26AP2 Motor drive .................................................................................. 40

26AP2:1 Power supply ......................................................................... 40

26AP2:2 Motor 1 drive (Wire feed at CN7)........................................... 41

26AP2:3 Motor 2 drive (Travel motion at CN6) .................................... 43

26AP2:4 Relay outputs......................................................................... 44

26AP2 Circuit board versions............................................................... 45

26AP2 Component positions................................................................ 46

TABLE OF CONTENTS

0740 801 028 © ESAB AB 2017

FAULT CODES ......................................................................................... 47

Error log .................................................................................................. 47

Error code description ........................................................................... 48

SERVICE INSTRUCTIONS....................................................................... 55

What is ESD? .......................................................................................... 55

Service aid .............................................................................................. 55

Replacing the battery ............................................................................. 56

SOFTWARE UPDATE............................................................................... 57

Motor control 26AP1 .............................................................................. 57

Welding data unit 1AP1.......................................................................... 57

Updating software ................................................................................ 60

Reset with reset.txt............................................................................... 61

SPARE PARTS ......................................................................................... 63

Rights reserved to alter specifications without notice.

READ THIS FIRST

0740 801 028

- 4 -

© ESAB AB 2017

READ THIS FIRST

Maintenance and repair work should be performed by an experienced person, and electrical
work only by a trained electrician. Use only recommended replacement parts.

This service manual is intended for use by technicians with electrical/electronic training for
help in connection with fault-tracing and repair.

Use the spare parts list as a guide to where the components are located in the equipment.
The spare parts list is published as a separate document, see "Spare Parts" section.

This manual contains details of design changes that have been made up to and including
July 2016.

The manual is valid for PEK with serial number 921-xxx-xxxx, 943-xxx-xxxx, 049-xxx-xxxx,
327-xxx-xxxx and 628-xxx-xxxx.

NOTE!

The unit is tested by ESAB in a general set-up. The responsibility for safety and
function, of the specific set-up, lies with the integrator.

CAUTION!

Read and understand the instruction manual before
installing or operating.

INTRODUCTION

0740 801 028

- 5 -

© ESAB AB 2017

INTRODUCTION

Block diagram of the PEK

Design structure of the control unit

PEK is a control unit for power sources intended for submerged arc welding (SAW) and for
gas metal arc welding (GMAW) The control unit includes a motor control for use together
with automatic welding machines, column and booms.

It has connections for:

• welding power source

• emergency stop

• CAN bus

• USB-memory (Fromserialno.628-xxx-xxxx the unit is equipped with a second USB
connector, located inside the unit on the MMC/Welding data board.)

• motors

• control of flux/gas

• encoders

• limit switches

• the ESAB WeldCloud™ Mobile unit (via Ethernet connection)
(fromserialno.628-xxx-xxxx)

1AP1 MMC module

The control unit has an MMC with processor, memory, control buttons and a display. The
MMC is connected to the welding power source and the motor control board with a 500
kbit/s CAN bus. The unit is powered with 12 V supplied via the CAN connection.

INTRODUCTION

0740 801 028

- 6 -

© ESAB AB 2017

26AP1 Motor control board

The motor control board handles the motor driver board, reads the motor encoders and the
limit switches. The unit is powered from the motor driver board except for the CAN circuits
supplied with 12 V via the CAN connection. The board can supply 5 V to a laser lamp and
5,15 or 24 VDC for the motor encoder.

26AP2 Motor driver board

The motor driver board is supplied with 42 VAC from the welding power source via a
rectifier. It has two H-bridge motor driver circuits making it possible to reverse the motors.
The board also holds the relay that controls flux or gas.

WIRING DIAGRAM

0740 801 028

- 7 -

© ESAB AB 2017

WIRING DIAGRAM

Component description

Component Description

1AP1 MMC module

1AP2 Display

1AP3 Buttons, rubber keypad

1L1, 26L1, X1L1 Ferrite ring cores

1L2 Ferrite ring core (from serial no. 628-xxx-xxxx)

26AP1 Motor control board

26AP2 Motor driver board

BR1 Rectifier bridge

C1 Filter capacitor

C2 Filter capacitor

S1 Emergency stop

X1 Terminal block

XP1 Connector

XS1/24AP1 CANbus connection

XS2 USB connector

XS3 Ethernet connector (from serial no. 628-xxx-xxxx)

200 Wire

14.2, 14.4, 14.5 Wire from CN14:1, CN14:4 and CN14:5

18.2 Wire from CN18:2

3.1, 3.3 Wire from CN3:1 and CN3:3

4.1, 4.3 Wire from CN4:1 and CN4:3

5.1, 5.5 Wire from CN5:1 and CN5:5

X1.4, X1.6, X2.1,
XB.2, X4.J, X4.A,
X6.B, X6.C, X9.F,
X1.G, XB.H

Wire from X1

CAUTION!

STATIC ELECTRICITY can damage circuit boards and
electronic components.

• Observe precautions for handling electrostatic
sensitive devices.

• Use proper static-proof bags and boxes.

WIRING DIAGRAM

0740 801 028

- 8 -

© ESAB AB 2017

A2, A6 PEK Control Unit, Serial no. 921-, 943-, 049-, 327-xxx-xxxx

Updates:

From serial no. 921-010-XXXX: Cable 18.1 removed

From serial no. 921-010-XXXX: Wire jumper X1:12 to X1:15 introduced

WIRING DIAGRAM

0740 801 028

- 9 -

© ESAB AB 2017

WIRING DIAGRAM

0740 801 028

- 10 -

© ESAB AB 2017

A2, A6 PEK Control Unit, Serial no. 628-xxx-xxxx

WIRING DIAGRAM

0740 801 028

- 11 -

© ESAB AB 2017

TECHNICAL DATA

0740 801 028

- 12 -

© ESAB AB 2017

TECHNICAL DATA

PEK

Supply voltage 42 V, 50/60 Hz

Power requirement Max 900 VA

Engine connections adapted for ESAB's
motors

6 A 100%

Speed control Feedback from pulse encoder

Operating temperature -15°C to +45°C

Transportation temperature -20°C to +55°C

Relative air humidity Max 95%

Dimensions l×w×h 246 × 235 × 273 mm

Weight 6.6 kg

Enclosure class IP23

Travel speed 0–200 cm/min *)

See separate instruction manual for
automatic welding machines.

Max manual travel speed 2.0 m/min

Wire feed speed, filler wire 0–2500 cm/min *)

See separate instruction manual for wire feed
unit.

*) The setting range is dependent on the product used.

Enclosure class

The IP code indicates the enclosure class, i.e. the degree of protection against penetration
by solid objects or water.

Equipment marked IP23 is intended for indoor and outdoor use.

INSTALLATION AND CONNECTIONS

0740 801 028

- 13 -

© ESAB AB 2017

INSTALLATION AND CONNECTIONS

The unit have several connections both external and internal. Some connections require
ready-made cables. These are availible as accessories. Use cable restrainers to secure the
cables.

For general information about operation, see the instruction manuals for the power source
and connected units.

External connections

1. Connection for control cable to welding

power source

6. Inlet for cable (travel motion pulse

encoder)

2. USB connection 7. Inlet for cable (arc voltage feedback)

3. Connection (CAN) for remote control unit

or service tool

8. Outlet for motor cable (travel motion)

4. Inlet for cable (limit switches, magnetic

gasvalve)

9. Outlet for motor cable (wire feed)

5. Inlet for cable (wire feed pulse encoder) 10. LAN connector, Ethernet port used to

connect to WeldCloud™ Mobile
(fromserialno.628-xxx-xxxx)

Connection for power source (1)

Connection for the welding power source with 42 VAC power supply, arc voltage feedback,
emergency stop and CAN bus.

NOTE!

To prevent damage to the equipment ensure that the right type of cable is used.

INSTALLATION AND CONNECTIONS

0740 801 028

- 14 -

© ESAB AB 2017

USB connection (2)

An external USB memory can be used to transfer programs to and from the systems.

Certain USB memories may not work with this equipment. We recommend using USB
memories from a reputable supplier.

NOTE!

We recommend that the USB memory, that is used together with this equipment,
shall not be used for any other purpose.

NOTE!

ESAB assumes no responsibility for any damage caused as a consequence of
incorrect use of the USB memory.

CAN, connection for remote control unit or service tool (3)

Two CANbus connections (500 kbit/s) for external equipment, remote control or the ESAT
servicetool.

Termination of CANbus

Inside the unit there are CANbus terminations at two of the boards:

• 1AP1 MMC, switch SW1. Factory setting; NOT terminated.

• 26AP1 motor control board. jumper CN29. Factory setting; terminated to 120 Ohm.

LAN/Ethernet connector (10)

From serial no. 628-xxx-xxxx the PEK control unit is equipped with an Ethernet interface to
be able to connect the unit to an ESAB WeldCloud™ Mobile unit. For further information
about the WeldCloud™ system, see the WeldCloud™ instruction manual. For further
information about the WeldCloud™ Mobile unit, see the combined W82and WeldCloud™

service manual.

INSTALLATION AND CONNECTIONS

0740 801 028

- 15 -

© ESAB AB 2017

Internal connections

1. X1 Terminal block for connection of limit

switches, flux/gas, 42VAC, arc voltage
andemergency stop

4. CN16 Connection for travel motion pulse

encoder

2. CN19, CN20 Voltage selection for

encoders

5. CN7 Connection for motor (wire feed)

3. CN17 Connection for wire feed pulse

encoder

6. CN6 Connection for motor (travel motion)

INSTALLATION AND CONNECTIONS

0740 801 028

- 16 -

© ESAB AB 2017

Emergency stop

There are provisions made for two separated emergency stop circuits controlled by the
same button.

Emergency stop, 1st circuit

This circuit is connected to the power source
and will shut down the welding power source
if it is engaged. The circuit can be extended
to other external emergency stop buttons
according to the right figure above.

• At terminal block X1, remove the link
between 1 and 2.

• At terminal block X1, connect the external
emergency circuit to 1 and 2.

Emergency stop, 1st circuit connections

Emergency stop, 2nd circuit

This circuit is not connected inside the unit. It
can be used to control other units that require
a separated emergency circuit.

Emergency stop, 2nd circuit connections

INSTALLATION AND CONNECTIONS

0740 801 028

- 17 -

© ESAB AB 2017

Connection for Flux/Gas valve

There is a relay output for steering a flux or
gas valve.

The internal relay is rated for max 8A/250
VAC. Named “Gas/Flux” in the menues.

• Connect to terminal block X1 at 17 and

18.

Example, connection of flux/gas valve

Connection optional equipment

Manufactured before serial no.
921-010-xxxx

There is a relay output for steering optional
equipment or ON/OFF of the laserlamp.

The internal relay is rated for max 8A/250
VAC. Named “Relay 2” in the menues.

• Connect optional equipment to terminal
block X1 at 15 and 16.

Manufactured after serial no. 921-010-xxxx

The internal relay is rated for max 8A/250
VAC. Named “Relay 2” in the menues.

When shipped from the factory the relay is
connected for ON/OFF of the laserlamp.
When connecting optional equipment the
power connection to the laserlamp must be
disconnected.

• Disconnect the cable between X1:12 and
X1:15

• Connect optional equipment to terminal
block X1 at 15 and 16.







Example, connection of optional equipment

INSTALLATION AND CONNECTIONS

0740 801 028

- 18 -

© ESAB AB 2017

Laser lamp supply 5 V

NOTE!

Not recommended circuit! Change to
24 V circuit, see below.

Manufactured before serial no.
921-010-xxxx

Power supply for light. Output 5 V.

• Connect to terminal block X1 at 19 (+5
V).

• Connect to terminal block X1 at 20 (0 V).

Connection for 5 V laser lamp

Laser lamp supply 24 V

Power supply for light. Output is 24 V with a
max current of 80mA.

With continuous power

• Connect to terminal block X1 at 14
(+24V).

• Connect to terminal block X1 at 20 (0V).

With ON/OFF function

Manufactured before serial no.
921-010-xxxx

With this configuration, ON/OFF of the light is
handled via the menues of the unit. Use the
soft button called “Relay 2”.

• Connect to terminal block X1 at 16
(+24V).

• Connect to terminal block X1 at 20 (0V).

• Insert a jumper wire from X1:12 to X1:15.

Manufactured after serial no. 921-010-xxxx

With this configuration ON/OFF of the light is
handled via the menues of the unit. Use the
soft button called “Relay 2”.

• Connect to terminal block X1 at 16
(+24V).

• Connect to terminal block X1 at 20 (0V).







Connection for 24 V laser lamp

INSTALLATION AND CONNECTIONS

0740 801 028

- 19 -

© ESAB AB 2017

Travel limit switches

There are two inputs for limit switches.

• At terminal block X1, remove link
between 11 and 12.

• At terminal block X1, remove link
between 13 and 14.

• Connect the first limit switch to terminal
block X1 at 11 and 12.

• Connect the second limit switch to
terminal block X1 at 13 and 14.

Connection for limit switches

Motor drive and field supply

Power connection to motor 1 and 2

There are outputs to drive two motors. The motors are connected directly to the 26AP2 motor
drive board with an ESAB accessory cable.

Motor 1 for wire feed, connect to CN7.

Motor 2 for travel, connect to CN6.

• At the back of the unit, remove the plug(s) from the hole(s).

• Push the board connector(s) through the hole(s) and secure the strain relief(s).

• Connect to the motordrive board 26AP1 at CN6 and/or CN7.

INSTALLATION AND CONNECTIONS

0740 801 028

- 20 -

© ESAB AB 2017

Motor encoder

Motor encoder

There are two inputs for reading motion. The inputs are designed for incremental quadrature
encoders with a supply voltage of 5, 15 or 24 VDC.

The encoders are connected directly to the 26AP1 motor control board with an ESAB
accessory cable.

Connect encoder for:

• motor 1 (wire feed) to CN17

• motor 2 (travel) to CN16.

Installation:

• At the back of the unit, remove the plug(s) from the hole(s).

• Push the board connector(s) through the hole(s) and secure it with the strain relief(s).

• Connect to motor control board 26AP1 at CN16 and/or CN17.

• At CN19 and CN20, select supply voltage for the encoders: 5 VDC, 15 VDC or 24

VDC. For A2 or A6, select 24 VDC.