Manual (in russian) TANGENT-3М : Download (701 Kb)

Functions of TANGENT-3М

• The automated setting for loss-angle tangent measurement of transformer oil TANGENT-3М is intended for defining a tangent of dielectric losses of transformer oil in accordance with State Standards (GOST) 6581-75 at the power frequency of 50 Hz.
• Setting TANGENT-3М should be run in premises at working values of a temperature range of +15- +35° С, of relative humidity 80 % at a temperature of +20° С and atmospheric pressure of 84,0 - 106,7 kPa (630 - 800 mm Hg).

Technical Data of TANGENT-3М

TANGENT-3М measures a tangent of dielectric losses, permittivity, electric capacity C and voltage U used to a measuring cell (a working voltage below), a temperature of a transformer oil test.

A range of tangent measurements of a loss angle	0,0001 - 1,0 (0,01 - 100 %)
An error in measuring tangent of a loss angle	(0,01 tg -0,0002)
Operating voltage used to a measuring cell, corresponding with a field intensity 1МV/м, V	2000
A range of working voltage measurements, V	0 - 2700
A limit of a safe relative basic error while measuring working voltage, %	1,0
A range of capacity measurements, pF	5 - 50
A limit of a safe relative basic error while measuring capacity, %	(0,5 + tg)
A range of a heater running, C	С10 - 100
Accuracy of temperature measurement, C	1
Time of measurement, including calibration and heating up to 90 degrees (with taking measurements in 10 degrees), minutes	30
Time of measurement, including calibration, heating up to 90 degrees (with taking measurements in 10 degrees) and cooling, minutes	80
A measuring cell in accordance with State Standard (GOST) 6581-75, three-electrode type
Volume of a cell, sm3	13-14
Voltage of a mains supply of a single-phase alternating current, V	205 - 235
Power consumption, kV-A, no more than	0,3
Overall dimensions, mm	405*260*90
Weight, kg, no more than	5

TANGENT-3М can be run with six different cells with saving their parameters in non-volatile memory and making it possible to view them from the menu.

TANGENT-3М keeps in non-volatile memory up to 2000 latest measurements. The delivery set includes software on a CD that allows you to copy a file containing results of measurements from an installation medium to a PC. The file can be written in MS Word or Excel formats. The PC is connected to an installation medium through the SPI (RS232C). The PC should be IBM - compatible and have the following characteristics: operational system Windows 95 (98); a free serial port (RS232).

Equipment of TANGENT-3М

NAME	DESIGNATION	QUANTITY
1. TANGENT-3М setting	ТМ-3М.00.00.00	1
2. A measuring cell YaPI-3	YaPI -3/00.00.00	3
3. A network cable	-	1
4. An interface cable for connection to a PC	-	1
5. A compact disc with software	-	1
DOCUMENTS
6. TANGENT-3М setting manual	ТМ-3М.00.00.00РЭ	1
7. A measuring cell YaPI-3. The registration certificate	YaPI -3/00.00.00ПС	3
8. Metrological certificate KhGTsSMS	-	1

The Device and the Principle of Operation of TANGENT-3М

A flow chart of the device is demonstrated on the picture

Дт is a temperature sensor; ПТН is a current- voltage converter; РПТН is an adjustable current- voltage converter; ТВН is a high voltage transformer; ФСИ is a lockout pulses shaper; УСН is a signal imbalance amplifier; ВАЦП is a vector analog-digital converter; СЭ is a sample condenser; МИ is an interface module; ПК is a PC.

TANGENT-3М Principle of Operation

The cell, the sample condenser (СЭ), ПТН (a current- voltage converter), РПТН (an adjustable current- voltage converter) form a bridge circuit of a measurement. УСН (a signal imbalance amplifier) strengthens an imbalance signal to a level necessary for effective operating of ВАЦП (a vector analog-digital converter). ВАЦП is a synchronous detector with supporting fluctuation and АЦП, connected to the output of УСН (a signal imbalance amplifier). Values of the codes read by the microcontroller from ВАЦП are proportional to the corresponding quadrature components of an imbalance signal.

Currents that can be compared are transformed to voltage of ПТН and РПТН, the adder produces an imbalance signal which amplifies by УСН and gets converted to codes of ВАЦП. The microcontroller balances two currents while running РПТН (conversion ratio is 0 1000).

ФСИ produces impulses that are synchronous with the frequency of a power system and a measuring signal. Stabilitrons VD1, VD2, switchboards K1 and К2, and safety locks are intended for protecting a measuring circuit from current overloads.

The calculations necessary for achieving a result are made by the microcontroller.

The measuring process can be divided into the following basic stages:

1. Measurement of working voltage;
2. A measuring circuit balancing;
3. Measurement result calculation using balancing values of a conversion ratio РПТН and the value of a residual signal of imbalance.

After balancing by means of ВАЦП the residual signal of imbalance is measured. Using the result of this measurement and a conversion ratio РПТН, and values of capacity and a tangent of a loss angle of a model circuit (Сэ), the microcontroller makes calculations and on a four-row LCD display shows the values of:

• a tangent of a loss angle of a measurement object;
• permittivity;
• an effective value of working voltage;
• temperatures of an oil test;
• a number of a test.

The microcontroller controls management of the elements participating in the performance of the above specified actions, the dialogue of an operator with the device, and measuring information transfer to the PC.

In the device the consecutive interface port (MI) for connection with the PC (RS232) is provided.

The Design of TANGENT-3М

TANGENT-3М setting consists of a measuring module, a heating module (a thermostat) with a capacity regulator, a source of high voltage (includes a transformer 220/2000 and a switchboard by means of which high voltage switches on), a sample vacuum condenser and a measuring cell of a three-tightening type.

The setting is equipped by the blocking device eliminating the possibility of high voltage submission when the panel is shifted. The module of high voltage has a scheme protecting from disruptions.

Menu Functions

All the actions concerning management of a measurement process are taken by means of a 16-button keyboard and a 4-line case indicator located on the top panel of the device.

Functions of the Buttons: "0" - "9" – to fix numerical values when setting time, a date, a number of an oil test, a number of a cell, etc.; "" - to go to the top register; "↑","↓", "←","→" - to move the cursor; "МЕНЮ " - the button to enter the menu modes and to approve entrance; "СТОП" - to stop the program, to go to the main menu; "ПУСК 1" and "ПУСК 2" - to choose a mode of measurements; "С0, tg0" - – to measure parameters of an empty cell (calibration)

The Menu

• An oil test
• A cell selection
• Time and date
• Viewing of the archive
  • Date and time
  • An oil test
  • The whole archive

After entering the Menu it is possible to choose various utilities, to change options of the device or to view the archive. To do this press the Menu button, with the buttons "^","v" move the cursor to the needed mode and press the menu button.