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CHAPTER E    GENERAL OPERATION AND DESIGN

E-1.

General

The AMPTEC RESEARCH 620ES Explosive 
Safety Igniter Tester is shown in the block dia-
gram (Figure E-1).  All diagrams and informa-
tion disclosed in this chapter  is proprietary and 
is included in order to make troubleshooting to 
component level possible.

The AMPTEC 620 Series Igniter Tester uses 
modern solid-state semiconductors exclusively 
and digital CMOS circuits extensively to mini-
mize power requirements and make battery 
operation useful and practical. AMPTEC also 
maintains a spare parts  inventory of all compo-
nents found in the 620ES Tester and it’s cus-
tomer service department can also provide 
additional assistance in the trouble shooting 
process. 

E-2.

Troubleshooting

Since the 620ES Tester is used to test potential 
deadly explosive force detonators and warheads 
of missiles etc., 

personnel that are not qualified 

to make such electrical repairs on the 620ES 
Tester should not even attempt to remove the 
calibration access screws or open the main 
panel or effect any repair whatsoever

Apparent 620ES Tester malfunctions can some-
times be the result of bad test lead/connection 
wiring, wrong connections, misinterpretation of 
specifications, low battery levels, and in rare 
cases due to an incomplete understanding of the 
instrument and how to use it. A thorough review 
of the operating instructions for this instrument 
is recommended prior to any component 
replacement.  Check to be sure that cables and 
other test equipment are in good working order 
before attempting to troubleshoot the 620ES 
series igniter tester .

If you turn on

 the AMPTEC 620ES Explosive 

Safety Igniter Tester 

and the

 display does not 

come on

,

 it usually means the batteries are 

dead and need charging

, or fuse needs replac-

ing.

If the 620ES exhibits problems that cannot be 
eliminated by reviewing Chapters B and D, the 
following guidelines have been established to 
help solve the problem.

E-2-1. Localizing the Problem

Chapter D-2 discusses how to use the 

Functional Test Box (FTB-620ES) with the

 

620ES Tester to help localize the problem. The 
key to successful troubleshooting is to localize 
the problem to a general electronic parameter as 
much as possible before trying to pin the 
problem down to a specific component.  Certain 
questions should be asked such as "Does the 
problem occur on all ranges or on a specific 
range only?".  If the 620ES Tester does not 
come on when powered up, did you check the 
rear panel fuse. The power supplies for both the 
current source and the digital voltmeter 
electronics are also one of the first things that 
should be tested. As it is not possible to 
anticipate all failure modes of the 620ES 
Explosive Safety Igniter Tester, servicing 
personnel should become familiar with this 
section to gain a complete understanding of the 
internal workings of the ohmmeter.

E-2-2.  Component Replacement

If the malfunction  is a faulty component, the 
accuracy of the 620 Series Igniter Tester can be 
maintained only if it is re-calibrated after a 
component replacement and the following 
precautions are taken:

Use only the specified component or its exact 
equivalent.  Spare parts can be ordered from 
your nearest AMPTEC RESEARCH Service 
Center or directly from the factory by referring 
to the AMPTEC Stock Number listed in the 
Parts Lists section at the back of this manual.

The highest quality 63/37 grade rosin core 
electronic grade solder with a 50W or lower 
maximum power soldering iron should be used. 
Never use an acid core solder as corrosion of 
components leads and PCB etch loss can occur.

Summary of Contents for 620ES

Page 1: ...L 09JUNE2011 REV E PHONE 512 858 4045 800 350 5105 website http www amptec com FAX 512 3858 4340 TOLL FREE IN USA 2 0 I 9999 Ohms Fullscale with 0 1 milliohm 100 Resolution 620ES Safety Igniter Tester...

Page 2: ...Requirements A 4 Setup and Use CHAPTER B 620ES FAILSAFE OHMMETER SPECIFICATIONS Table B 2 Specifications CHAPTER C REPLACEMENT OPTIONAL ANDACCESSORYITEMS C 1 Available Accessories and Options C 2 Tes...

Page 3: ...Safe Power Supply Scheme Figure E 1 Model 620ES Block Diagram Figure E 1B Analog to Digital Converter Timing Diagram Figure E 2 Analog Section of IC1 and IC2 Figure E 3 Constant Current Source Diagram...

Page 4: ...20ES Should the rechargeable batteries reach a low charge level a negative sign will apear on the display The 620ES has a battery monitoring circuit that indicates it is time to plug in the battery ch...

Page 5: ...On time An Overnight charge usually restores the 620ES to a Fully Charged ready to use state The main Power switch has two separate modes The ON position supplies internal battery isolated power to o...

Page 6: ...ithin minute s of power turn on unless your in an extremely cold temperature allow more time for warm up 15 minutes A quick check for no sign of the low battery indicator and test lead integrity check...

Page 7: ...20K ohm ranges 0 002 per C from 0 C 15EC and 35 C 50 C Instrument Display 20 000 count 4 digit Super Bright Light Emitting Diodes LED Over Range Indication select next higher range Display flashes Mea...

Page 8: ...Rack Mount Adapter Option 620RACK includes an adapter tray that allows any AMPTEC 620 series tester to be flush panel mount installed in a standard 19 equipment rack C 2 Test Lead Sets and Probes Opt...

Page 9: ...y interface A High Go Low BCD Dual Limit Comparator is presently under development and will be available Summer of 2001 Option 300 4 Wire Gold Plated Kelvin Lead Set Option 300 is a general purpose Go...

Page 10: ...e used for calibration purposes Simpsontm DC Milliammeter Range 0 10 mA fullscale Accuracy 3 FTSR1 01 23572 0 1W 1 0 Resistor Tc 25ppm C W FTSR2 01 23575 10 0W 0 1 Resistor Tc 10ppm C W FTSR3 01 23577...

Page 11: ...log 10 mA full scale milliammeter and a variety of test resistors is available from AMPTEC RESEARCH D 1 General Operation This section contains operating instructions for the AMPTEC 620ES Explosive Sa...

Page 12: ...O to output a single data string 1 resistance reading r0 De Selects all Ranges r1 Selects the 2 0 Ohm Range r2 Selects the 20 Ohm Range r3 Selects the 200 Ohm Range r4 Selects the 200K Ohm Range V Ve...

Page 13: ...20ES unless you are qualified D 3 4 Wire Resistance Measurement The four terminal configuration of the 620ES eliminates measurement errors normally caused by in series test lead resistance and contact...

Page 14: ...condition when ever the test lead terminals are open or the resis tance under test is a higher value than the range selected on the AMPTEC 620 tester Connecting VHI to IHI and Vlo to Ilo eliminates th...

Page 15: ...main power switch must be switched OFF to charge the batteries In the OFF position the main power switch disables all ohmmeter measurement circuitry and connects the internal battery pack to the char...

Page 16: ...iter Testers output terminals Imax Current Maximum Calculation 1 6V 110 ohms 0 014 Amperes 15mA max A simple startup test procedure which also has the 620ES Explosive Safety Tester user perform a func...

Page 17: ...on it usually means the batteries are dead and need charging or fuse needs replac ing If the 620ES exhibits problems that cannot be eliminated by reviewing Chapters B and D the following guidelines h...

Page 18: ...r move the replacement part until the solder has cooled Cold solder and bad solder joints can cause more problems Use the chassis ground connect to the common terminal of the functional test section c...

Page 19: ...s care of the digital part of the 4 digit 20 000 count dual slope conversion COUNTERS DISPLAY COMPARATOR BUFFER MULTIPLEXER ZERO CROSSING DETECTOR INTEG UUT CONTROL LOGIC INPUT SWITCH DC CONSTANT CURR...

Page 20: ...EGRATOR INTEGRATOR COMPARATOR COMPARATOR CAZ CAZ CSTRAY CSTRAY RINT RINT FIGURE E 2B PHASE ll INTEGRATE INPUT FIGURE E 2C PHASE lll AND DE INTEGRATE CINT CINT VIN VIN CREF CREF 3 3 1 1 2 2 6 6 5 5 4 4...

Page 21: ...ished in Phase I The time or number of counts required to do this is proportional to the input voltage E 4 1 Reference Voltage The precision reference voltage required to do the A D conversion is deve...

Page 22: ...C 620ESTester Igniter Tester schematic will show that the output of IC202 6 is actually applied to the base of transistor Q202 which acts as a current limiter The worst case component failure that cou...

Page 23: ...y Scheme The 5 volt power supply is provided directly by the batteries for driving the LED displays and digital logic The 5VD is used for driving IC8 the low battery detection circuit The 15V power su...

Page 24: ...ginning the calibration procedure The calibration adjustments are accessed by removing the screws in the feet of the unit then lifting off the lid to access the main PCB trimpots The locations of the...

Page 25: ...ents necessary for the 200 KOhm and 200 Kohm ranges Contact AMPTEC s customer service department if further technical support is necessary F 4 Battery Replacement Instructions The rechargeable NICAD b...

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