Miyachi Unitek 100DP User manual

USER'S MANUAL 990-295
Revision B June 2007
100DP/300DP DUAL PULSE
STORED ENERGY
RESISTANCE WELDING POWER SUPPLIES
Model Stock No.
100DP/115 1-293-01
100DP/230 1-293-01-01
300DP/115 1-294-01
300DP/230 1-294-01-01

100DP/300DP DUAL PULSE RESISTANCE WELDING POWER SUPPLY
ii 990-295
Copyright © 2005 Miyachi Unitek Corporation
The engineering designs, drawings and data contained herein are the
proprietary work of Miyachi Unitek Corporation and may not be
reproduced, copied, exhibited or otherwise used without the written
authorization of Miyachi Unitek Corporation.
Printed in the United States of America.
Revision Record
Revision EO Date Basis of Revision
A 20633 12/05 None. Original edition.
B 21448 6/07 Added open load detection feature

100DP/300DP DUAL PULSE RESISTANCE WELDING POWER SUPPLY
990-295 iii
CONTENTS
Page
Revision Record ........................................................................................................................................ ii
Contact Us .........................................................................................................................................v
Safety Notes ....................................................................................................................................... vi
Chapter 1. Description
Section I: Features .................................................................................................................................. 1-1
Features ..................................................................................................................................... 1-1
Description ..................................................................................................................................... 1-2
Section III: Major Components ............................................................................................................. 1-4
Major Components ........................................................................................................................... 1-3
Front Panel Display and Display Controls ............................................................................... 1-3
Schedule Number and Chain Switch ........................................................................................ 1-4
Energy and Pulse Indicators, Pulse Edit Buttons, Up/Down Buttons ...................................... 1-4
Polarity Select ........................................................................................................................... 1-7
Charge Monitor ........................................................................................................................ 1-7
WELD/NO WELD Switch ....................................................................................................... 1-7
Emergency Stop Switch Operation .................................................................................................. 1-7
Chapter 2. Installation and Setup
Section I: Installation ............................................................................................................................. 2-1
Unpacking ..................................................................................................................................... 2-1
Space Requirements ......................................................................................................................... 2-1
Utilities ..................................................................................................................................... 2-2
Power ..................................................................................................................................... 2-2
Compressed Air and Cooling Water ......................................................................................... 2-2
Input Logic Configuration ............................................................................................................... 2-2
Section II: Setup ..................................................................................................................................... 2-3
Connections to External Equipment ................................................................................................ 2-3
Weld Head Connections .................................................................................................................. 2-4
Foot Pedal-Actuated Weld Head Connection .................................................................................. 2-5
EZ-AIR Weld Head Connections ..................................................................................................... 2-6
Chapter 3. Operation
Section I: Introduction ........................................................................................................................... 3-1
Before You Start .............................................................................................................................. 3-1
Pre-Operational Checks ................................................................................................................... 3-1
Connections .............................................................................................................................. 3-1
Power ..................................................................................................................................... 3-1
Compressed Air ........................................................................................................................ 3-1
Adjust Buzzer Loudness .................................................................................................................. 3-1

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iv 990-295
CONTENTS (Continued)
Page
Chapter 3. Operation (Continued)
Initial Setup ..................................................................................................................................... 3-2
Section II. Operation .............................................................................................................................. 3-3
Using Existing Weld Schedules ....................................................................................................... 3-3
Modify Weld Schedules .................................................................................................................. 3-3
Using the WELDS Counter ............................................................................................................. 3-4
Using LIMIT Set .............................................................................................................................. 3-4
Chain Schedules 1 & 2 .................................................................................................................... 3-5
Dual Weld Head Operation ............................................................................................................. 3-5
Programming Lock ........................................................................................................................... 3-5
Schedule Lock .................................................................................................................................. 3-5
Chapter 4. Maintenance
Section I. Troubleshooting ..................................................................................................................... 4-1
Troubleshooting ............................................................................................................................... 4-1
Error Codes .................................................................................................................................... 4-2
Section III. Maintenance ........................................................................................................................ 4-4
Calibration ..................................................................................................................................... 4-4
Electrode Maintenance .................................................................................................................... 4-4
Parts Replacement ........................................................................................................................... 4-4
Section IV. Repair Service ..................................................................................................................... 4-5
Appendix A. Technical Specifications ............................................................................................... A-1
Appendix B. Electrical and Data Connections ..................................................................................B-1
Appendix C. System Timing ...............................................................................................................C-1
Appendix D. The Basics of Resistance Welding ............................................................................... D-1
Appendix E. Quality Resistance Welding Solutions: Defining the Optimum Process .................E-1

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CONTACT US
Thank you for purchasing a Miyachi Unitek™ Resistance Welding System Control.
Upon receipt of your equipment, please thoroughly inspect it for shipping damage prior to its
installation. Should there be any damage, please immediately contact the shipping company to file a
claim, and notify Miyachi Unitek at:
1820 South Myrtle Avenue
P.O. Box 5033
Monrovia, CA 91017-7133
Telephone: [phone]
FAX: [phone]
e-mail: [email protected]
The purpose of this manual is to supply operating and maintenance personnel with the information
needed to properly and safely operate and maintain the Miyachi Unitek™ 100DP and 300DP Resistance
Welding System Control.
We have made every effort to ensure that the information in this manual is accurate and adequate.
If you have any questions, or if you have suggestions to improve this manual, please contact us at the
above location/numbers.
Miyachi Unitek Corporation is not responsible for any loss due to improper use of this product.

100DP/300DP DUAL PULSE RESISTANCE WELDING POWER SUPPLY
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SAFETY NOTES
DANGER
•Lethal voltages exist within this unit.Never perform any maintenance inside this unit.
•Never perform any welding operation without wearing protective safety glasses.
This instruction manual describes how to operate, maintain and service the 100DP and 300DP
Resistance Welding Power Supplies, and provides instructions relating to its safe use. A separate
manual provides similar information for the weld head used in conjunction with the power supply.
Procedures described in these manuals must be performed, as detailed, by qualified and trained
personnel.
For safety, and to effectively take advantage of the full capabilities of the weld head and power supply,
please read these instruction manuals before attempting to use them.
Procedures other than those described in these manuals or not performed as prescribed in them, may
expose personnel to electrical or burn hazards.
After reading these manuals, retain them for future reference when any questions arise regarding the
proper and safe operation of the power supply.
Please note the following conventions used in this manual:
WARNING: Comments marked this way warn the reader of conditions which might result in
immediate death or serious injury.
CAUTION: Comments marked this way warn the reader of conditions which might result in either
damage to the equipment, or injury to the individual.

100DP/300DP DUAL PULSE RESISTANCE WELDING POWER SUPPLY
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CHAPTER 1
Description
Section I: Features
Features
The Miyachi Unitek 100DP/300DP Dual Pulse Resistance Welding Power Supply precisely controls
welding energy and weld head timing.
•Multi-function microprocessor control
provides repeatable process control and is
compatible with air or manually actuated
weld heads. Facilitates multiple applications
at a single work-station and protects weld
schedules from changes by unauthorized
personnel.
•Dual pulse welding eliminates weld splash.
Improves weld quality, especially when
welding plated materials.
•Alternating polarity allows the user to set up
a pulse to change from positive to negative
polarity each time the welder is fired. This
allows the user to equalize the wear between
two electrodes in many parallel gap welding
processes.
•Two air valve drivers are provided to
sequentially control two separate air operated
weld heads, if desired. As shipped, Air
Valve Driver 1 is configured to drive a 24
VAC weld head, but can be reconfigured to
drive a 24VDC weld head instead. Air Valve
Driver 2 can only drive a 24VDC weld head.
•Three relays provide signals for when the unit is ready to weld, when a weld is completed, and when
the weld counter has reached its preset limit.
•Remote schedule selection simplifies use in automated systems. A CONTROL SIGNALS connector
accepts remote control signals for Emergency Stop, Remote Weld Inhibit, and Remote Weld
Schedule Selection.
•The chain schedule feature allows Schedule 1 and Schedule 2 to be chained together.
•Schedule protection and system security features protects weld schedules from changes by
unauthorized personnel.

CHAPTER 1: DESCRIPTION
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•The schedule lock feature allows you to restrict welding to one selected weld schedule.
•The digital display allows operators to set welding energy accurately and quickly.
•The Power Supply is compatible with manually actuated weld heads and air actuated heads with 1-
level or 2-level foot switches.
•The Power Supply is compatible with force fired and non-force fired weld heads. Squeeze (delay)
time is adjustable from 0 to 2.999 seconds.
•A built-in weld counter allows you to control events which are a function of the number of welds
made.
•The firing circuit uses single pole, double pole or optical firing (pressure) switches.
•The energy monitor and lockout helps prevent poor welds caused by firing the power supply before
the capacitor bank is properly charged or discharged.
•The line failure turndown safety feature discharges the capacitor bank when input power is
interrupted.
•The Power Supply is protected from radio frequency interference and electromagnetic interference,
resulting in reliable operation even in high electrical noise environments. Input switch debounce
circuitry eliminates false triggering.
Detailed instructions on using these features are located in Chapter 3, Operating Instructions.
NOTE: For the rest of this manual, the Miyachi Unitek 100DP/300DP Dual Pulse Resistance
Welding Power Supply will simply be referred to as the Power Supply.
Description
The Power Supplies are versatile, 100 Watt-second and 300 Watt-second stored energy, capacitor
discharge, dual pulse power supplies which can effectively solve most precision, small parts,
resistance welding problems.
You can program up to 15 weld schedules and save them in memory. A built-in schedule protection
feature protects weld schedules from unauthorized or inadvertent changes. The exclusive charge
monitor and firing lockout feature guarantees that weld quality is independent of line voltage
fluctuations and the speed at which the power supply is operated.
Dual pulse welding improves weld quality and eliminates weld splash. Dual pulse means each weld is
performed with two pulses with independent energy levels and independent polarity. The first pulse
displaces the plating or contamination and reforms the surface so that it is in intimate contact with the
electrode. The second pulse welds the base metals.
The remote schedule feature allows the Power Supplies to reliably select weld schedules in automated
applications.
The Power Supplies can be used with manual, user actuated, or air actuated weld heads. The units are
designed to operate at either 100-120VAC or 200-240VAC, 50/60 Hz.

CHAPTER 1: DESCRIPTION
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Section II: Major Components
Major Components
The major components are the front panel, which contains the operator’s controls and indicators, and the
rear panel, which contains fuses, circuit breakers and power and signal connectors. The rear panel
connections are discussed in Chapter 2, Installation and Setup.
Front Panel Display and Display Controls
The front panel of the Control below shows controls and indicators. The function of each item is
described on the following pages.
Front Panel Controls

CHAPTER 1: DESCRIPTION
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Schedule Number and Chain Switch
The 2-digit LED displays which welding schedule is selected for use.
The CHAIN SCH 1-2 button will “chain” Schedule 1 and Schedule 2 together,
meaning welding pulses will alternate between these two schedules. The green
light on this switch will be ON when the “chain” function is in use.
Welding will continue repeating between these schedules until you press the
CHAIN SCH 1-2 button again and the green light on the button goes OFF. Welding
will then continue from a single schedule.
Energy and Pulse Indicators •Pulse Edit Buttons •UP/DOWN Buttons
The 3-digit LED displays the energy for each pulse in Watt-
seconds (Ws).
When in the “edit” mode, this display will flash until editing is
complete.
PULSE and POLARITY indicators. These displays will light up to
indicate which pulse length and polarity has been selected for each
pulse.
Press either of these buttons for approximately 1 second to put the Power Supply
into the “edit” mode. This enables you to modify the settings for each weld
schedule.
Press the Pulse 1 button and wait for the LED to flash. When the LED flashes,
you can change the energy, pulse length, and polarity for Pulse 1. To accept the
changes, press the Pulse 1 button again and the LED will stop flashing. To exit
the “editing” mode without accepting changes, press the clear button or any
other button on the front panel.
Press the Pulse 2 button and follow the same procedures to modify Pulse 2.