Transformer Oil Tester Machine

Structure and Function

(1). Structure

1. switch-on
2 .step-on 
3.step-down
4.stir  
5.stew

a. reset
b. run   
c. keep
d. alarm  
e. print  
f. display

(2). Function

Use “preset” to preset the times for testing, stirring time, and stewing time. The running process is indicated by LED lights. The light “T” (times)indicates time, and “KV”(kilovolt) indicates voltage. The showing window on the right relatively shows the times and voltage value or time.

• Reset: when the device does not work well, press the key and the device returns to its original state.
• Run: press the key, and the device works with the preset parameters
• Keep: it takes effect when the device runs. Press the key and the
• voltage stops rising, and the output voltage keeps the value just now at the same time. Press the running key and the voltage will rise again; press the keeping key for a little longer, and the voltage will drop.
• Alarm: press it to choose warning or not.
• Print: press the key, then the values during the test will be printed out automatically.
• Display: Press this key, and the voltage values and the average value will be displayed in proper order.

Operation Step

(1) Preparations

1. Use the alcohol to clean the outside edge of the oil cup; for the water or impurity may pollute the sample oil and therefore lead to a decrease in the dielectric strength of the oil.
2. Earth the instrument reliably.
3. Put the magnet into the cup and put some sample oil into the cup, screwthe two high-tension electrode poles into the high-tension chamber, and lay the cup in the flute of the two poles. Then close the high-tension chamber when you can hear the sound of the jiggle switch on the left edge of the chamber. If not, it shows you don’t close the chamber completely, and then if you begin the test, the instrument will warn you with a ringing sound. Therefore, you have to close the chamber completely.
   (All the steps above should be operated under the circumstance of power-off!!!!)
4. Connect the lines between the main ark and the high-pressure ark
5. Preset the parameters, the presetting times, mix-round time, and quiescence time should not be set to 0; otherwise, the instrument will warn you with a ringing sound when you begin to test. Of course, the instrument refuses to run.
6. Connect the instrument to the power supply with the line we offer to you; one end of the line should be connected to the place “ Power 220V” on the surface of the panel.

(2)Testing method

1. Turn the power on
① If the LEDs(light-emitting diode) change their shows as follows:
9999->8888->7777->6666->5555->4444->3333->2222->1111->0000, and at last the LEDs stay at the “0000” state.Then the instrument can receive the operating orders.
The process of normal testing: after receiving “run” order à“stir”à“stew”à“step-on”à“step-don”(the sample oil has been broken down)à “voltage-down”.
②  If the instrument is in the process of slowing down voltages, you should let it slow down completely, and when it goes into the process of mix-round, you can press “reset” to make the instrument turn to ①.

2. Press the “run” key at the “0000” state of the LEDs, then the instrument will strictly follow the parameters that you set, to test the oil. As soon as the test is over, the buzzer will make a beep to tell you the experiment is complete. And the LEDs display the average value of the whole test, the “times” LED will display“P”.

3. Use the “display” key to look over all the data tested, and press the “print” key to print out all the data.

Precautions

Test the oil without being purified by the transformer oil filtration machine.

• The poor oil is the reclaimed oil without being filtrated ; and the poorer oil contains plenty of water and impurity, whose dielectric strength is mostly under 12KV(kilovolts). To the poor oil with more water, a certain client wants to know how bad the oil is; he also tests it with the instrument which tests the high dielectric strength. As a result ,the high-voltage testing system of the instrument is damaged. The cause of the damage is : (See figure 1)

• Under normal circumstances, there is insulating oil filled between the two hemispheres of the high voltage poles. When testing, the voltage difference becomes bigger as the electromotor steps in, as different oils can endure different voltages, so the tested oil will be broken down by the ascending voltage when it’s bigger than the breakdown voltage, then there will be a heavy current transient caused by the breakdown. According to the current, the instrument turns off the switch to cut off the high voltage and turns to the state of “voltage down”.
• When the poor oil contains more water, the water particulate will be shaped into a vaporous line under the high voltage. And as the voltage between the two hemispheres continues to ascend, the line becomes thicker, and the resistance of the water becomes smaller. But the process doesn’t have a sudden breakdown discharge, so the instrument won’t collect a signal to cut off the high voltage; therefore, the instrument will be damaged, for example, the current limiting resistor or the safety circuit will be burned out.

1.1 test of the low withstand voltage oil

The dielectric strength of this kind of oil is usually between 15 kV and 35KV. The instrument can test normally even if the oil contains a little water and impurity. It’s just because during the process of the pressure’s ascending, several air bubbles(or impurities)will be absorbed between the two hemispheres to cause the discharge, then the bubbles will be pile out to the air and the space left will be supplied by the oil nearby. Therefore, the voltage can continue to increase to break down the oil to the maximum endurance point.
  

1.2 test of the poor oil

Poor Oil Conditions

• Dielectric strength is typically just above 10kV.
• Visible water droplets or impurities → Do not test.
• After 24+ hours, large water droplets sink, and tiny bubbles rise.
• Sample oil must be drawn from the middle using a clean, dry, water-free vessel.

During Testing

• Observe for vaporous lines (Fig. 1) between hemispheres as voltage rises.
• If seen → Turn off power immediately.
• If continuous discharging occurs and the instrument doesn’t auto-shutoff → Stop testing immediately.

Vessel Requirements

Must be clean and dry for sampling/containing oil.

Safety & Operation

• Do not open the high-voltage chamber cover during operation.
• If malfunctioning → Check safeties; replace broken ones with same-type replacements.
• After sudden power loss → Instrument resumes last operation but loses one count value → Reset and retest.

Recommended Settings

• Quiescence time: 5 minutes.
• Mix round time: 80 seconds.

Long-Term Storage

If unused for extended periods → Power on for 1 hour monthly.

Dealing with the simple faults

Fault Symptoms	Methods
No display	① make sure the power is on ② whether the safeties is broken ,one safety is in the socket, the other is on the surface of the panel
The display is normal, but there is alarm after pressing the “run” key.	The high pressure chamber is closed incompletely or the jiggle switch is broken.
The display is normal, there is no  alarm after pressing the “run” key, but there’s no voltage’s ascending	The safety on the surface of the panel is broken, replace with a 5A safety.
The words are small when printing, or the paper doesn’t come out.	The printing paper is rolled too tightly. Open the panel of the printer, make the paper loose.
The printed words are dim	Replace the ribbon for the printer

Box up lists

1. set host computer
2. piece of power supply line
3. oil cup
4. magnon
5. copy of using manual
6. copy of acceptance certificate
7. reel of print paper
8. copy of printer’s manual