DIGITEST ELECTRONIC

LIVE THE EXPERIENCE IN TECHNICAL SERVICE!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ELECTRONIC PCB TESTING DEVICE D&T 500

D&T500 VI FAULT LOCATOR WITH CRT TUBE

Fast and economical fault locating in analogue and digital pcbs without sustentation tension!

 

The task of technical services is being difficult every passing day!

PCBs have become more complex and more diversified. Documentation is inadequate and it is quite difficult to find qualified technical service technicians.

Though these difficulties complicate the work, we have to keep up customer satisfaction. If there is a possibility to repair electronic pcbs in a faster and efficient way, inexperienced personnel can manage to repair pcbs easily. The system which facilitates repairing enables time advantage. 

D&T500 is designed for these reasons:

 

1. Easy usage! Even for the inexperienced staff!

2. Convenient for each kind of electronic equipment testing!

3. The facility of detecting the malfunction of the pcbs about which
    there is no information

4. Automatic undamaged/damaged comparison!

5. Automatic indication of malfunction with undamaged/damaged

 

Fault locating without sustentation:

It can be hazardous to supply electricity to a damaged car ;even impossible. Functional ATE systems and general testing equipment Oscilloscope can be used only with the pcbs whose sustentation is provided. Additionally documentation of circuit and earnest technical knowledge is needed. D&T500 is designed to repair the pcbs to which electricity is not supplied.

How does it work?

D&T500 applies current limited AC signal tension to circuit. The dynamic impedance characteristic of applied device is displayed in CRT screen. To gain the best display, D&T500 adjusts the signal level automatically and enables the technician to see the characteristic exactly.

 

D&T500’s  Trigger feature provides testing of three-terminal components .when trigger end is connected base end of transistor or gate end,  it can be observed how these devices have been interactive.

 

Each circuit can test any component:

With observation of analogue characteristic signals, analogue can work on every kind of digital, electromechanic circuit components. For most of ICs get out of order because of input-output pins, it is quite logical way to observe analogue characteristics. For example; like pins which are short circuit or open circuit and currency leakage…

The most convenient damage research for ICs about which there is no data is in this way. 

 

Standard equipment: Test probes,40 IC Test clips

Need of power: 200-250V AC 50/60 Hz 45VA

Line fuses assets: 200-250V, 200mA

 

 

D&T500 TECNICAL FEATURE
TEST voltage and  Frequencies	Open circuit voltage
LOGIC	10V  5mA
LOW	10V  150mA
MEDIUM	20V  1mA
HIGH	50V  1mA
LOCK	Can limit the selected levels
TEST SWITCHING
MANUEL	Just selects  one driver  echelon.
AUTO	Selects convenient level   automatically .
CYCLE	Tests in every level elected with step  quantity.
TEST FREQUENCIES
LOW	90Hz
MEDIUM	500Hz
HIGH	2kHz
CHANNELS
CHANNEL A-B	Receives  input  from A and B probes.
DISPLAY MODES
A	Just displays  A channel
B	Just displays  B channel
A and B	Displays  A and B  channels  simultaneously.
PULSE GENERATOR
PULSE 1 - PULSE 2  MOD	DC, signal type 1,signal type 2
LEVEL	0-5 V
WITDH	Adjusts  pulse width ( DC signal type  1,signal type 2)

 

 

1) What is V-I curve? 

We call voltage/current rate V-I .This rate reveals impedance. Every electronic equipment has a V-I characteristic curve .there can be changes in the characteristic of the curves of damaged components. These changes can be detected easily even when the component is in circuit. For instance ;Semiconductor Burned Out Due To Overload Will Turn Into Resistance Carbonizing And So Will Indicate Resistance Characteristic.This is A Perfect Damage.Being In Circuit Or Out-Of-Service Will Set Off This Damage Better.

 

2) Main V-I curves:

V-I curves needed to be known essentially is given below.in these graphics, the horizontal axis is voltage axis ,and vertical axis is currency axis.in some old oscilloscope, there was v-i mode.in fact it can be thought as two parallel panels.vertical axis apply deflection according to currency and horizontal axis does according to voltage.in conclusion, V-I curves are not different from private oscilloscope curves.  

 

 

 

 

1- Resistor Curve

 

 

 

 

 

 

 

 

2- Zener diode curve: there is no transition of conduct on the left side of diode characteristic.

 

 

 

3- Capacitor-Bobbin curve:

these curves are elliptically shaped.yet in respect of center they are symmetrical. . for there is internal resistance in bobbin curves, the circle becomes horizontal on a vertical platform.

 

these are the main curves stated here. they should be seen out-of-service. every electronic component can be tested. (certainly it is possible to detect whether the problem of components is damaged or not by programmers). these curves give quite significant data about component damage.it is not important that components are surface-montage (smd) or in sip, dip covered structure,smd components get obviously damaged for  the fact that   p-n  funtions  are more sensitive.these faults can be more easily located by  V-I test.

 

3-Fault Locating WITHIN V-I CURVE:

We said that v-i curves change in damaged components.if such is the case ; we specialize in v-i curve test, we can test the damaged component in /out of circuit and determine the error.if we have a safe electronic circuit , comparing  v-i curves we can localize the points of damaged components and locate the fault.

 

That is, without the need of circuit schema and sustentation of pcb we can easily locate the fault.. For the expert users on v-i curves, there will not always be the need of undamaged pcb. Ok but is it possible to locate the fault conveying the data of pcb to the computer storage? Possible, moreover this data can be shared by other device users around the world.it would be so nice to see the names of these pcbs beside download links.

 

You can cross this question in your mind: how can we test all components basing resistance, diode, bobbin and capacitor? Test of resistance is easy because it is possible within one millimeter .diode test is ok. Transistor consists of two diodes. Its test is easy too.3- pin components like fet, mosfet and transistor indicates semiconductor V-I curves.
In every pin of ICs, there are fuse -aimed zener diodes.

 

As it is seen in the figure, these diodes are located by sustentation or earth (ground). If you do not see proper diode characteristic in every IC, out-of-service it means the component is damaged.

 

 

These zener diodes are between vcc and/or GND.That is, they indicate diode curves. If any curve similar to resistance curve or partly damaged curve can be seen in comparison to other pins, it means IC is damaged. 

Lineer,pins making the same work with components, indicates V/I curves. If there are 8 inputs ,all of these must indicate the same curve. If one of them is different the IC is likely to be damaged.

 

Designed By Tek Nokta Bilişim Hizmetleri