Amada 125DP User manual

STORED ENERGY POWER SUPPLY
125DP
OPERATION MANUAL
990-270 Rev J

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
ii 990-270
Copyright © 2002, 2013, 2014, 2015 Amada Miyachi America
The engineering designs, drawings and data contained herein are the proprietary work of Amada
Miyachi America and may not be reproduced, copied, exhibited or otherwise used without the
written authorization of Amada Miyachi America.
Printed in the United States of America.
Revision Record
Revision EO Date Basis of Revision
A 16610 4/96 Correct schedule save instructions
B 16841 9/96 Correct power supply output voltages for calibration procedure
C 17831 3/99 Complete revision of Calibration Procedures (Paragraph 8.03)
D 18576 11/99
Add tolerance to pulse output voltage.
Add Letter of Conformity.
E 19146 10/01 Complete Update
F 42762 8/13 Updated technical information and calibration values.
G 42840 11/13 Update to Miyachi America name and logo.
H 43479 12/14 Update to Amada Miyachi America name and logo.
J 43808 7/15 Update to Amada format.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 iii
FOREWORD
Thank you for purchasing a Miyachi Unitek Dual Pulse 125 Stored Energy Resistance Welding
Power Supply.
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 us at:
Amada Miyachi America
1820 South Myrtle Ave.
Monrovia, California 91017-7135
Phone: [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 Dual Pulse 125 Stored Energy Resistance
Welding Power Supply.
We have made every effort to ensure that the information in this manual is accurate and adequate.
Should questions arise, or if you have suggestions for improvement of this manual, please contact us at
the above location/numbers.
Amada Miyachi America is not responsible for any loss due to improper use of this product.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
iv 990-270
SAFETY NOTES
This instruction manual describes how to operate, maintain and service the Dual Pulse 125 Stored
Energy Resistance Welding Power Supply, and provides instructions relating to its SAFE use.
Procedures described in this manual MUST be performed, as detailed, by QUALIFIED and TRAINED
personnel.
For SAFETY, and to effectively take advantage of the full capabilities of the tester, please read these
instruction manuals before attempting to use the workstation.
Procedures other than those described in this manual or not performed as prescribed in it, may expose
personnel to electrical hazards.
After reading this manual, retain it for future reference when any questions arise regarding the proper
and SAFE operation of the tester.
Please note the following conventions used in this manual:
WARNING: Comments marked this way warn the reader of actions which, if not followed, might
result in immediate death or serious injury.
CAUTION: Comments marked this way warn the reader of actions which, if not followed, might result
in either damage to the equipment, or injury to the individual if subject to long-term exposure to the
indicated hazard.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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CONTENTS
CHAPTER 1: SYSTEM DESCRIPTION ........................................................................ 1-1
Section I. Features........................................................................................................... 1-1
Section II. System Components...................................................................................... 1-2
Front Panel Description ............................................................................................. 1-2
Front Panel Keys........................................................................................................ 1-3
Indicators and Displays.............................................................................................. 1-4
Rear Panel .................................................................................................................. 1-6
CHAPTER 2: GETTING STARTED ............................................................................... 2-1
Location ........................................................................................................................ 2-1
Power Line ....................................................................................................................... 2-1
Welding Cables................................................................................................................ 2-2
Firing Switch.................................................................................................................... 2-3
Manually Actuated Weld Heads ................................................................................ 2-3
Air Actuated Weld Heads .......................................................................................... 2-3
Installing Air Actuated Weld Heads ................................................................................ 2-4
Air Valve Driver ........................................................................................................ 2-5
Footswitch........................................................................................................................ 2-5
1-Level Footswitch .................................................................................................... 2-5
2-Level Footswitch .................................................................................................... 2-6
Options ........................................................................................................................ 2-6
Footswitch Weld Abort.................................................................................................... 2-6
Pulse Width Changes ....................................................................................................... 2-7
Replace Cover.................................................................................................................. 2-8
External Inputs Options ................................................................................................... 2-8
CHAPTER 3: OPERATING INSTRUCTIONS .............................................................. 3-1
Section I. Preparing for Operation .................................................................................. 3-1
Power Up ................................................................................................................... 3-1
Select State................................................................................................................. 3-1
Select Schedule .......................................................................................................... 3-2
Change Energy Level................................................................................................. 3-2
Dual Pulse Welding ................................................................................................... 3-2
Welding Rate ............................................................................................................. 3-3
Set Electrode Force .................................................................................................... 3-3
Ready to Weld............................................................................................................ 3-3
Section II. Operation....................................................................................................... 3-4
Programming Weld Schedules................................................................................... 3-4
Program State....................................................................................................... 3-4

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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Change 1st Pulse .................................................................................................. 3-4
Change 2nd Pulse................................................................................................. 3-4
Power Up Schedule.............................................................................................. 3-5
Copying Information in Schedule 0 to another schedule..................................... 3-5
Programming Squeeze Time................................................................................ 3-6
Schedule Protection ON....................................................................................... 3-7
Schedule Protection OFF ..................................................................................... 3-7
CHAPTER 4: DEVELOPING WELD SCHEDULES .................................................... 4-1
Resistance Welding Parameters....................................................................................... 4-1
Procedure ........................................................................................................................ 4-2
Weld Head Parameter: Electrode Force.......................................................................... 4-2
125 DP Power Supply – Parameter: PULSE WIDTH, % ENERGY,
NUMBER OF PULSES................................................................................................... 4-3
Dual Pulse Operation ....................................................................................................... 4-3
Make a Weld .................................................................................................................... 4-3
Evaluate the Weld ............................................................................................................ 4-4
Weak Weld................................................................................................................. 4-4
Electrode Sticking...................................................................................................... 4-4
Causes of Imperfect Welds .............................................................................................. 4-4
Electrode Force and % ENERGY.............................................................................. 4-5
Polarity....................................................................................................................... 4-5
Weld Strength Profiles..................................................................................................... 4-6
Evaluate Results............................................................................................................... 4-6
Electrode Maintenance..................................................................................................... 4-7
CHAPTER 5: MAINTENANCE ....................................................................................... 5-1
Modification and Calibration........................................................................................... 5-1
Modification of Line Voltage .......................................................................................... 5-1
Calibration........................................................................................................................ 5-2
Troubleshooting ............................................................................................................... 5-4
Repair Service.................................................................................................................. 5-4
Telephone Service...................................................................................................... 5-4
Factory Service Repair............................................................................................... 5-5
APPENDIX A: TECHNICAL SPECIFICATIONS ......................................................... A-1
Stored Energy Rating....................................................................................................... A-1
Energy Display................................................................................................................. A-1
Line Voltage..................................................................................................................... A-1
Fusing ........................................................................................................................ A-1

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 vii
Circuit Breaker(s)....................................................................................................... A-1
Power ........................................................................................................................ A-1
Capacitor Bank........................................................................................................... A-2
Line Voltage Regulation ............................................................................................ A-2
Turndown Circuit....................................................................................................... A-2
Line Failure Turndown .............................................................................................. A-2
Over-Voltage Lockout ............................................................................................... A-2
Charge Lockout Circuit.............................................................................................. A-2
Weld Fire Lockout ..................................................................................................... A-3
Output Pulse Characteristics...................................................................................... A-3
Welding Speed................................................................................................................. A-3
Dual Pulse Welding Speed......................................................................................... A-5
Power Cord ................................................................................................................ A-6
Firing Switch.............................................................................................................. A-6
Footswitch Connector ................................................................................................ A-6
Air Valve Driver ........................................................................................................ A-6
Cooling....................................................................................................................... A-7
External Inputs Connector ......................................................................................... A-7
Physical Characteristics ................................................................................................... A-8
Index...................................................................................................................................... Index-1
ILLUSTRATIONS
Figure Title Page
1-1 Dual Pulse 125 Front View.................................................................................. 1-1
1-2 Dual Pulse 125 Indicators and Displays .............................................................. 1-4
1-3 Rear Panel of the Dual Pulse 125 ........................................................................ 1-6
2-1 Typical Set-up diagram for the 125 DP showing both manually actuated and
Air Actuated Weld Head connections.................................................................. 2-1
2-2 Correct Terminal Connection .............................................................................. 2-2
2-3 Examples of Cable Routings................................................................................ 2-3
2-4 Solenoid Air Valve Assembly for Thinline Model 80A...................................... 2-4
2-5 Footswitch Weld Abort Jumper in the ON Position ............................................ 2-7
2-6 Location of terminals 1-4 on the Pulse Transformer ........................................... 2-7
2-7 Change jumper connections on the Pulse Transformer to select pulse width...... 2-8
2-8 Remote Schedule Selection via BCD Coded Switches........................................ 2-10
2-9 Remote Schedule Selection BCD Code............................................................... 2-10

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
viii 990-270
4-1 A graphic presentation of the effects of % ENERGY, Time and Pressure on
the Weld ............................................................................................................... 4-2
4-2 Typical Weld Strength Profile ............................................................................. 4-6
5-1 Line Voltage pins on Control Board.................................................................... 5-2
A-1 Hit Rate of 125 DP with 1500 µF and 750 µF Capacitor Bank........................... A-4
A-2 Repetition Rate, Maximum Continuous welding speed of Model 125DP........... A-5
A-3 125DP Outline Drawings..................................................................................... A-9
Tables
Table Title Page
4-1 Causes of Imperfect Welds .................................................................................. 4-5
5-1 Line Voltage pins on Control Board.................................................................... 5-2
A-1 Line Voltage......................................................................................................... A-1
A-2 Output Pulse Characteristics................................................................................ A-3
A-3 Welding Speed ..................................................................................................... A-4

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 ix
LIMITED WARRANTY
1. (a) Subject to the exceptions and upon the conditions set forth herein, Seller warrants to Buyer that
for a period of one (1) year from the date of shipment (“Warranty Period”), that such Goods will be free
from material defects in material and workmanship.
(b) Notwithstanding the foregoing and anything herein to the contrary, the warranty set forth in this
Section 1 shall be superseded and replaced in its entirety with the warranty set forth on Exhibit A
hereto if the Goods being purchased are specialty products, which include, without limitation, laser
products, fiber markers, custom systems, workstations, Seller-installed products, non-catalogue
products and other custom-made items (each a “Specialty Products.”
(c) EXCEPT FOR THE WARRANTY SET FORTH IN SECTION 1(A), SELLER MAKES NO
WARRANTY WHATSOEVER WITH RESPECT TO THE GOODS (INCLUDING ANY SOFTWARE) OR
SERVICES, INCLUDING ANY (a) WARRANTY OF MERCHANTABILITY; (b) WARRANTY OF
FITNESS FOR A PARTICULAR PURPOSE; (c) WARRANTY OF TITLE; OR (d) WARRANTY
AGAINST INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OF A THIRD PARTY;
WHETHER EXPRESS OR IMPLIED BY LAW, COURSE OF DEALING, COURSE OF
PERFORMANCE, USAGE OF TRADE OR OTHERWISE.
(d) Products manufactured by a third party and third party software (“Third Party Product”) may
constitute, contain, be contained in, incorporated into, attached to or packaged together with, the
Goods. Third Party Products are not covered by the warranty in Section 1(a). For the avoidance of
doubt, SELLER MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO ANY
THIRD PARTY PRODUCT, INCLUDING ANY (a) WARRANTY OF MERCHANTABILITY; (b)
WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE; (c) WARRANTY OF TITLE; OR (d)
WARRANTY AGAINST INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OF A THIRD
PARTY; WHETHER EXPRESS OR IMPLIED BY LAW, COURSE OF DEALING, COURSE OF
PERFORMANCE, USAGE OF TRADE OR OTHERWISE. Notwithstanding the foregoing, in the event
of the failure of any Third Party Product, Seller will assist (within reason) Buyer (at Buyer’s sole
expense) in obtaining, from the respective third party, any (if any) adjustment that is available under
such third party’s warranty.
(e) Seller shall not be liable for a breach of the warranty set forth in Section 1(a) unless: (i) Buyer gives
written notice of the defect, reasonably described, to Seller within five (5) days of the time when Buyer
discovers or ought to have discovered the defect and such notice is received by Seller during the
Warranty Period; (ii) Seller is given a reasonable opportunity after receiving the notice to examine such
Goods; (iii) Buyer (if requested to do so by Seller) returns such Goods (prepaid and insured to Seller at
1820 South Myrtle Avenue, Monrovia, CA 91016or to such other location as designated in writing by
Seller) to Seller pursuant to Seller’s RMA procedures and Buyer obtains a RMA number from Seller
prior to returning such Goods for the examination to take place; and (iii) Seller reasonably verifies
Buyer’s claim that the Goods are defective and that the defect developed under normal and proper use.
(f) Seller shall not be liable for a breach of the warranty set forth in Section 1(a) if: (i) Buyer makes any
further use of such Goods after giving such notice; (ii) the defect arises because Buyer failed to follow
Seller’s oral or written instructions as to the storage, installation, commissioning, use or maintenance of
the Goods; (iii) Buyer alters or repairs such Goods without the prior written consent of Seller; or (iv)
repairs or modifications are made by persons other than Seller’s own service personnel, or an
authorized representative’s personnel, unless such repairs are made with the written consent of Seller
in accordance with procedures outlined by Seller.

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STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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(g) All expendables such as electrodes are warranted only for defect in material and workmanship
which are apparent upon receipt by Buyer. The foregoing warranty is negated after the initial use.
(h) Subject to Section 1(e) and Section 1(f) above, with respect to any such Goods during the Warranty
Period, Seller shall, in its sole discretion, either: (i) repair or replace such Goods (or the defective part)
or (ii) credit or refund the price of such Goods at the pro rata contract rate, provided that, if Seller so
requests, Buyer shall, at Buyer’s expense, return such Goods to Seller.
(i) THE REMEDIES SET FORTH IN SECTION 1(H) SHALL BE BUYER’S SOLE AND EXCLUSIVE
REMEDY AND SELLER’S ENTIRE LIABILITY FOR ANY BREACH OF THE LIMITED WARRANTY
SET FORTH IN SECTION 1(A). Representations and warranties made by any person, including
representatives of Seller, which are inconsistent or in conflict with the terms of this warranty, as set
forth above, shall not be binding upon Seller.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 xi
Exhibit A
Warranty for “Specialty Products”
Limited Warranty
EXCEPT FOR THE WARRANTY SET FORTH BELOW IN THIS EXHIBIT A, SELLER MAKES NO
WARRANTY WHATSOEVER WITH RESPECT TO THE GOODS (INCLUDING ANY SOFTWARE) OR
SERVICES, INCLUDING ANY (a) WARRANTY OF MERCHANTABILITY; (b) WARRANTY OF
FITNESS FOR A PARTICULAR PURPOSE; (c) WARRANTY OF TITLE; OR (d) WARRANTY
AGAINST INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OF A THIRD PARTY;
WHETHER EXPRESS OR IMPLIED BY LAW, COURSE OF DEALING, COURSE OF
PERFORMANCE, USAGE OF TRADE OR OTHERWISE.
Warranty Period: The Warranty Period for Specialty Products is for one (1) year, and the Warranty
Period for laser welders and laser markers is two (2) years (unlimited hours), and the Warranty Period
for the laser pump diodes or modules is two (2) years or 10,000 clock hours, whichever occurs first (as
applicable, the “Warranty Period”). The Warranty Period begins as follows: (i) on orders for Goods
purchased directly by Buyer, upon installation at Buyer’s site or thirty (30) days after the date of
shipment, whichever occurs first; or (ii) on equipment purchased by a Buyer that is an OEM or systems
integrators, upon installation at the end user’s site or six (6) months after the date of shipment,
whichever occurs first.
Acceptance Tests: Acceptance Tests (when required) shall be conducted at Amada Miyachi
America, Inc., Monrovia, CA, USA (the “Testing Site”) unless otherwise mutually agreed in writing prior
to issuance or acceptance of the Acknowledgement. Acceptance Tests shall consist of a final visual
inspection and a functional test of all laser, workstation, enclosure, motion and accessory hardware.
Acceptance Tests shall include electrical, mechanical, optical, beam delivery, and software items
deliverable under the terms of the Acknowledgement. Terms and conditions for Additional Acceptance
Tests either at Seller’s or Buyer’s facility shall be mutually agreed in writing prior to issuance or
acceptance of the Acknowledgement.
Performance Warranty: The system is warranted to pass the identical performance criteria at Buyer’s
site as demonstrated during final Acceptance Testing at the Testing Site during the Warranty Period, as
provided in the Acknowledgement. Seller explicitly disclaims any responsibility for the process results
of the laser processing (welding, marking, drilling, cutting, etc.) operations.
Exclusions: Seller makes no warranty, express or implied, with respect to the design or operation of
any system in which any Seller’s product sold hereunder is a component.
Limitations: The limited warranty set forth on this Exhibit A does not cover loss, damage, or defects
resulting from transportation to Buyer’s facility, improper or inadequate maintenance by Buyer, Buyer-
supplied software or interfacing, unauthorized modification or misuse, operation outside of the
environmental specifications for the equipment, or improper site preparation and maintenance. This
warranty also does not cover damage from misuse, accident, fire or other casualties of failures caused
by modifications to any part of the equipment or unauthorized entry to those portions of the laser which
are stated. Furthermore, Seller shall not be liable for a breach of the warranty set forth in this Exhibit A
if: (i) Buyer makes any further use of such Goods after giving such notice; (ii) the defect arises because
Buyer failed to follow Seller’s oral or written instructions as to the storage, installation, commissioning,
use or maintenance of the Goods; (iii) Buyer alters or repairs such Goods without the prior written
consent of Seller; or (iv) repairs or modifications are made by persons other than Seller’s own service
personnel, or an authorized representative’s personnel, unless such repairs are made with the written
consent of Seller in accordance with procedures outlined by Seller.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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Seller further warrants that all Services performed by Seller’s employees will be performed in a good
and workmanlike manner. Seller’s sole liability under the foregoing warranty is limited to the obligation
to re-perform, at Seller’s cost, any such Services not so performed, within a reasonable amount of time
following receipt of written notice from Buyer of such breach, provided that Buyer must inform Seller of
any such breach within ten (10) days of the date of performance of such Services.
Seller shall not be liable for a breach of the warranty set forth in this Exhibit A unless: (i) Buyer gives
written notice of the defect or non-compliance covered by the warranty, reasonably described, to Seller
within five (5) days of the time when Buyer discovers or ought to have discovered the defect or non-
compliance and such notice is received by Seller during the Warranty Period; (ii) Seller is given a
reasonable opportunity after receiving the notice to examine such Goods and (a) Buyer returns such
Goods to Seller’s place of business at Buyer’s cost (prepaid and insured); or (b) in the case of custom
systems, Seller dispatches a field service provider to Buyer’s location at Buyer’s expense, for the
examination to take place there; and (iii) Seller reasonably verifies Buyer’s claim that the Goods are
defective or non-compliant and the defect or non-compliance developed under normal and proper use.
All consumable, optical fibers, and expendables such as electrodes are warranted only for defect in
material and workmanship which are apparent upon receipt by Buyer. The foregoing warranty is
negated after the initial use.
No warranty made hereunder shall extend to any product whose serial number is altered, defaced, or
removed.
Remedies: With respect to any such Goods during the Warranty Period, Seller shall, in its sole
discretion, either: repair such Goods (or the defective part). THE REMEDIES SET FORTH IN THE
FOREGOING SENTENCE SHALL BE BUYER’S SOLE AND EXCLUSIVE REMEDY AND SELLER’S
ENTIRE LIABILITY FOR ANY BREACH OF THE LIMITED WARRANTY SET FORTH IN THIS
EXHIBIT A. Representations and warranties made by any person, including representatives of Seller,
which are inconsistent or in conflict with the terms of this warranty, as set forth above, shall not be
binding upon Seller.
Products manufactured by a third party and third party software (“Third Party Product”) may
constitute, contain, be contained in, incorporated into, attached to or packaged together with, the
Goods. Third Party Products are not covered by the warranty in this Exhibit A. For the avoidance of
doubt, SELLER MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO ANY
THIRD PARTY PRODUCT, INCLUDING ANY (a) WARRANTY OF MERCHANTABILITY; (b)
WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE; (c) WARRANTY OF TITLE; OR (d)
WARRANTY AGAINST INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OF A THIRD
PARTY; WHETHER EXPRESS OR IMPLIED BY LAW, COURSE OF DEALING, COURSE OF
PERFORMANCE, USAGE OF TRADE OR OTHERWISE. Notwithstanding the foregoing, in the event
of the failure of any Third Party Product, Seller will assist (within reason) Buyer (at Buyer’s sole
expense) in obtaining, from the respective third party, any (if any) adjustment that is available under
such third party’s warranty.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 1-1
CHAPTER 1
SYSTEM DESCRIPTION
Section I: Features
The Miyachi Unitek™ Dual Pulse 125 (125DP) is a stored energy, capacitor discharge, power supply
designed to perform precision resistance welding. The circuitry is solid state, microprocessor controlled,
with components conservatively rated when used within the maximum specified repetition rates. The
charging circuit uses silicon controlled rectifiers in a patented manner which provides high reliability
and precise charging intervals. Special precautions protect against false triggering in high RFI and EMI
environments. It is a multi-voltage unit designed for operation at 100, 115, 200/208, or 230 VAC, 50/60
Hz. The features of the 125DP include:
Energy selectable up to 125 watt-seconds
Dual Pulse Capability which simplifies welding to plated materials
Digital Display allows operators to set energy levels accurately and quickly
Stores up to 8 Different Weld Schedules which facilitates multiple applications at a single
work station
Remote Schedule Selection for use in automation
Air Head Capability is standard feature which allows it to control air actuated welding
heads
Programmable Squeeze Time for non-force fired weld heads
Schedule Protection Feature protects Weld Schedules from changes by unauthorized
personnel
Weld Fire Lockout prevents welding whenever the energy level is not within 1% of the
preset level therefore weld quality is independent of line voltage and the speed at which
the power supply is operated
Protected from Radio Frequency Interference and Electro-Magnetic Interference to ensure
reliable operation even in high electrical noise environments
Multiple Line Voltages - can operate at 100, 115, 200/208, or 230 VAC, 50/60 Hz.

CHAPTER 1: SYSTEM DESCRIPTION
DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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Section II: System Components
Front Panel Description
POWER SWITCH - Used to switch both sides of the incoming power line.
WELD/NO WELD SWITCH - Welding current will not flow when this switch is in the NO WELD
position. For Air Operated Weld Heads, the Air Valve Driver will still actuate the weld head. This
switch must be in the WELD position in order to make a weld.
NOTE: Instructions to "Select WELD or NO WELD" mean that you are to place this switch in either the
WELD or the NO WELD position, whichever is indicated inside the brackets.
POWER OUTPUT TERMINALS - Positive (+) and Negative ( -) terminals provide taps for bolt on
connection of Welding Cables to the Weld Head or Handpiece.

CHAPTER 1: SYSTEM DESCRIPTION
DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 1-3
Front Panel Keys
The eight keys on the Front Panel are identified as follows:
KEY DESCRIPTION
SCHEDULE ▲Changes (increases) the SCHEDULE number which is displayed. Schedules 0
through 7 can be selected.
SCHEDULE ▼Changes (decreases) the SCHEDULE number which is displayed.
ENERGY ▲Changes (increases) the %ENERGY displayed up to a maximum of 100%. Also
used to change SQUEEZE TIME up to a maximum of 9.9 seconds.
ENERGY ▼
Changes (decreases) the %ENERGY displayed down to a minimum of 0.6%.
NOTE: The 2ND Pulse display can be decreased to 000%. Also used to change
Squeeze Time down to a minimum of 0.1 seconds, or 0.0 to disable.
1ST PULSE
Causes the 125DP to enter the PROGRAM State so that the user can change the
FIRST PULSE %ENERGY for the current schedule. When already in the
Program State, press and hold 1ST PULSE and press ENERGY ▲▼ to change
SQUEEZE TIME.
2ND PULSE
Causes the 125DP to enter the PROGRAM State so that the user can change the
SECOND PULSE %ENERGY for the current schedule. The %ENERGY
DISPLAY will change to display the 2ND Pulse %Energy.
RUN
Causes the 125DP to exit the PROGRAM State without saving the changed
schedule. The changed schedule will become Schedule 0 and will NOT be
written to permanent memory. Welding is done in the RUN State.
SAVE
In the PROGRAM State, saves (writes) any schedule to permanent memory. The
125DP will then exit the PROGRAM State and return to RUN State. This key has
no function in the RUN State.
NOTE: Instructions to "press [ ]", mean that you are to press the key described inside the brackets.
For example: "Press 1ST PULSE" means press the key labeled 1ST PULSE PROGRAM. "Press
[SCHEDULE ▲▼" means press either the ▲or the ▼located beneath the SCHEDULE NUMBER.

CHAPTER 1: SYSTEM DESCRIPTION
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STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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Indicators and Displays
Dual Pulse 125 Indicators and Displays
A READY INDICATOR - The green LED (light emitting diode) indicator lights when power
supply is ready and welding is permitted. Welding is allowed only when the capacitors are
properly charged and WELD is selected. The READY INDICATOR will not light in the
PROGRAM State.
B SCHEDULE NUMBER DISPLAY - Indicates the currently selected Schedule Number. Press
SCHEDULE ▲▼ to select Schedules 0 through 7. The SCHEDULE NUMBER DISPLAY is
also used at power up to briefly display the first digit of the Software Version Number. The
125DP will then go to the RUN State and display the last Schedule saved in memory.
C ENERGY DISPLAY - Indicates Energy setting for the currently displayed schedule number.
Energy settings are shown as a percent of total energy, 125 watt-seconds. PERCENT ENERGY
can be set from 0.6% to 100%. The 1st Pulse %Energy is always displayed in the Run State.
The 2nd Pulse %Energy is displayed when the 2nd Pulse Indicator is flashing in the Program
State.
D 2ND PULSE INDICATOR - Flashes when 2ND PULSE is pressed and the power supply is
placed in the PROGRAM State. The 2nd Pulse %Energy is only displayed when the 2nd Pulse
Indicator is flashing. In the RUN State, the 2nd Pulse Indicator will stay lit to indicate that a 2nd
Pulse has been programmed.
NOTE: The digital display may not increment in continuous steps, however, it will always be within ±
0.6% of the desired setting. At power up, the Energy Display will briefly display the last 3 digits
of the Software Version Number and then the status of the Schedule Protection Feature. In the
PROGRAM STATE, when 1ST PULSE is pressed, the Energy Display is used to display
SQUEEZE TIME.
E 1ST PULSE INDICATOR - Flashes when 1ST PULSE is pressed and the power supply is
placed in the PROGRAM State. In the RUN State, the 1st Pulse Indicator is always lighted.
F FIRING SWITCH INDICATOR - The red decimal point, next to the SCHEDULE NUMBER,
will light when the Force Firing Switch in the weld head closes. This feature is a convenience
when setting the electrode firing force.

CHAPTER 1: SYSTEM DESCRIPTION
DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
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Rear Panel
Figure 1-3. Rear Panel of the Dual Pulse 125
GCB1, CB2 - Circuit breaker(s) used to protect both sides of the incoming power line.
HPOWER CABLE - 5 foot cable is terminated with the appropriate 115 or 230 volt plug. The
standard connector for the 115 VAC power supply is the NEMA 5-15P rated for 15 amps.
IAIR VALVE DRIVER - Provides either 24 or 115 volts (AC) to Miyachi Unitek Air Actuated
Weld Heads.
JMECHANICAL FIRING SWITCH - 5 foot cable is used to connect the 125DP to the Force
Firing Switch in all Miyachi Unitek Weld Heads and Handpieces.
KFOOTSWITCH RECEPTACLE - Used to connect either a 1 Level or 2 Level Miyachi Unitek
Footswitch. Footswitches are only used with air or electrically actuated weld heads.
LEXTERNAL INPUTS - 9-pin, sub-miniature "D" connector used for Remote Schedule Selection.
See Chapter 2.
MOPTIONAL FIRING SWITCH - An additional firing switch can be wired in this position.

DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
990-270 2-1
CHAPTER 2
GETTING STARTED
Section I: Planning for Installation
Location
It is recommended that the power supply be installed in a well-ventilated area, free from dirt and
moisture. Air intake for cooling is through the underside, do not place on deep carpet, felt, or foam
pads. Air exits through the left side, allow sufficient clearance so that cooling air may flow properly.
Position the power supply as close as possible to the weld head.
Power Line
CAUTION: Do not connect the line cord at this time.
This power supply was wired for a specific voltage which was marked on the line cord during the
manufacturing process. The standard 125DP is wired for 115 VAC. Re-connection for operation at
another voltage may be made by a qualified technician. Refer to Chapter 5 - Calibration and
Modifications.
Figure 2-1. Typical set-up diagram for the 125DP showing both Manually
Actuated and Air Actuated Weld Head connections.
125DP
POWER
SUPPLY
115VAC, 15A
50/60 Hz, 1Ø
HOT COM GND
(BLK) (WHT) (GRN)
POWER
EXTERNAL INPUTS
INB GND 2
2
2
1
2
0
GND
1 5 3215
2
2
2
1
2
0
CHARGE
INHIBIT
REMOTE
SCHEDULE
SELECTION
USER SUPPLIED SWITCHING
FOOTSWITCH
LEVEL
1
GND
LEVEL
2
2341
12
INITIATE
AIR
VALVE
DRIVER
24VAC
24/115
RTN
115VAC
AUTO
SENSE
POWER
OUTPUT
MECHANICAL
FIRING
SWITCH
1
2
3
4
(SEE NOTE 3)
AIR
SOLENOID
24/115VAC
ELECTRODES
WELD CABLES
(SEE NOTE 2)
1
2(SEE NOTE 1)
FORCE
FIRING
SWITCH
WELD
HEAD
NOTES:
1 For non-force fired weld head opertion,
short pins 1 and 2 on the Firing Switch
connector.
2 Tie the weld cables together.
3. Dashed lines represent air actuated weld
head connections.

CHAPTER 2: GETTING STARTED
DUAL PULSE 125
STORED ENERGY RESISTANCE WELDING POWER SUPPLY
2-2 990-270
Welding Cables
Position the 125DP on the work bench approximately 5 inches behind the weld head. Use the cables
which are furnished with the weld head to connect the terminals on the back of the weld head to the
appropriate terminals on the transformer. Convention is to connect the lower electrode of the weld head
or handpiece to the (+) Power Output Terminal and the upper electrode to the ( - ) Power Output
Terminal of the power supply. Refer to Chapter 5 - POLARITY
For proper cable connections and to reduce energy losses follow these recommendations:
aUse the #2 AWG Welding Cables especially if the cables are more than 12 inches long. The
diameter of the cables should be as large as practical.
bUse the shortest possible Welding Cables. It is not uncommon to have losses of up to 50% per foot
for #6 cables and 20% for #2 cables.
cBolt terminals together, DO NOT place washers between the terminals of the power supply and the
terminals of the cables. Tighten connections securely, they must be free from oxidation, dirt and/or
grease. See figure 2-2.
dRoute cables so that they do not surround magnetic materials such as air solenoids, tooling, or steel
weld heads. See figure 2-3.
eTape cables together to minimize the inductive losses. A separation of weld cables surrounding an
area of one square foot could result in losses of up to 65%.
Figure 2-2. Correct Terminal Connection
Bolt
Washer
Terminal
Nut