Huazheng HZG User manual

HZG
Dry Type Testing Transformer
Huazheng Electric Manufacturing (Baoding) Co., Ltd

Warning and Caution
In order to prevent against electric shock for personal safety and damages of instruments
and equipment under testing, users should pay attention to reliable control and
reasonable utilization. Users must abide by the following rules at any time:
Before connecting with power source, testing transformers must be grounded!
Power source can not be connected before grounding!

Contents
Dry Type Testing Transformer........................................................................................................ 1
I.Product Introduction...............................................................................................................1
II.Technical Target.................................................................................................................... 1
III.Major Technical Parameters.............................................................................................. 1
IV.Operating Principle.............................................................................................................. 2
V.Methods of Application.........................................................................................................3
VI.Precautions...........................................................................................................................4
HZXZ Control Box............................................................................................................................ 6
I. Product Overview..................................................................................................................8
II. Working Principle................................................................................................................. 8
III. Technical Parameters,Specifications and Selection and Matching............................9
IV. Operational Guidelines...................................................................................................... 9
V. Use and Maintenance.......................................................................................................10
VI. Conditions of Use.............................................................................................................10
Packing List..................................................................................................................................... 11

1
Dry Type Testing Transformer
I.Product Introduction
This series transformer uses advanced production equipment, and new technology of coil
winding epoxy vacuum pouring and CD-type iron core, which obviously reduce weight and
volume, improve insulating strength and humidity resistance level, effectively weaken
leakage magnet resulting in greatly enhance the ability to withstanding impact of testing
short circuit current of transformer.
This series products have features of light weight, small volume, beautiful appearance,
stable performance, convenient usage and carrying, especially suitable for site operation,
are new generation high voltage testing transformer used for AC and DC in China. This
series products are applicable to power system and all power users to detect on site the
insulating performance test of all electrical equipment, high voltage power sources of all
appliance's voltage system or equipment with DC high voltage small current.
II.Technical Target
1. Impedance voltage: 4.5%-8%
2. Surface temperature rise: sine wave
3. Idle load loss consumption: 0.2%-0.35%
4. Allowable continuous operation time: 2 hours
5.Interrupted operation time: continuous
III.Major Technical Parameters
Model
Capacity
(KVA)
Input
voltage
(V)
Output
voltage
(KV)
Output
current
(mA)
Output
DC high
voltage
(KV)
Max. External
dimension
(mm)
Weight
(kg)
HZG-1.5/50
1.5
200
(400)
50
30
70
250x180x370
13
HZG-3/50
3
60
330x270x600
30
HZG-5/50
5
100
400x330x700
48
HZG-6/50
6
120
300x310x680
46
HZG-10/50
10
200
430x370x750
73
HZG-20/50
20
400
470x370x750
85
HZG-30/50
30
600
500x380x780
120
HZG-5/100
5
100
50
140
430x370x105
67

2
0
HZG-10/100
10
100
470x370x105
0
80
HZG-20/100
20
200
510x410x880
120
HZG-30/100
30
300
580x380x880
160
HZG-50/100
50
500
650x460x101
0
230
Remarks: Products can be manufactured according to the parameters provided by
customers.
IV.Operating Principle
Input voltage of this series products is 200V, using principle of electromagnetic induction
and changing input voltage according to demand to make output high voltage
continuously adjust from 0V to rated maximum value.
When DC withstand voltage and leakage current testing are conducted, the input voltage
can be changed as long as high voltage silicon stack is rotary installed at high voltage
output terminal resulting in achieving DC high voltage output with different value.
For detailed working principle of this series products see Figure (1), if used as cascade, its
wiring see Figure (2).
Figure (1)
HZG：Testing transformer JS：Time relay
TY：Self-adjusting voltage regulator FM：Alarm equipment
LJ：Over-current relay D1, D2 and D3：Indicator light
C：AC contactor RD：Fuse

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K：Main power switch K1：Power switch of time relay
AK：Zero limit switch of voltage regulator AQ：Start button
CL：High voltage silicon stack AT：Stop button
A：Output ammeter KV:Output voltmeter
Figure (2)
V.Methods of Application
(1) Before testing, the shell “ ” terminal of high voltage testing transformer and
grounding “ ” terminal of power control box must be properly grounded,
otherwise, it will be harmful to personal and equipment safety.
(2) Before operation, users must be aware of the electric principle wiring diagrams of
high voltage testing transformer and power control box. During checking DC
withstand voltage and leakage testing, high voltage silicon stack or microammeter
can be suspended at high voltage terminal of high voltage testing transformer.
(3) When preparation is ready and the circuit is right after checking, the main power
can be closed, the red switch indicator light is also on at this time. If the light is not
on, handle of voltage regulator should be turned back to zero position at
anticlockwise direction. The indicator light on red stop button is on, otherwise start

4
button will refuse cooperation.
(4) Pressing start button, the indicator light of green button will turn on, at this time,
evenly and slowly turning handle of voltage regulator clockwise at the speed of
1.5-2KV/s. Make high voltage gradually rise and paying close attention to
indication and testing products of ammeter until adjust the high voltage required
by test.
(5) The withstand testing time for the testing products can be set by toggle timer, then
pressing time and alarm switch, i.e. Testing product's withstand voltage in
specified time, then informing by alarm. If the testing products are punctured,
over-current relay will trip automatically, the ammeter value will read number at
this time, the number is the value of puncturing voltage by products.
(6) If the testing products need protection are punctured, discharge voltage of
protective ball can be adjusted to about 1.15 times that of testing voltage at
continuous protective ball's gap on high voltage side.
(7) Schematic Diagram for High Voltage Testing:
Power source Control box Testing transformer
HV divider
Testing products
VI.Precautions
1. The insulating testing products of high voltage appliance should be safe and correct.
In addition to know well the manual of this product, the operation must be

5
implemented in accordance with relevant national standards and plans:
GB/T16927-1996 High-Voltage Experimentation Technology and DL/T596-1996
Preventive Testing Regulations for Electrical Equipment.
2. Due to the design characteristics and structure limitation of this series products,
continuous operation under rated output capacity should not exceed 2 hours. If the
products need to be used again, the power can be connected until power off for 2
hours. Continuous operation can be done under two thirds of rated voltage and two
thirds of rated current.
3. In normal insulation of high voltage appliance, this series products are not allowed to
operate in case of exceeding rated output voltage.
4. When this series products consist of cascade high voltage test, users should pay
special attention to check the correctness of conditions and wiring of Class 2 and 3
transformer's main body and insulating bracket, as well as the protective grounding
of entire system and conditions of protective grounding.

6
HZXZ Control Box
Dear Customers：
Thank you for purchasing our control box. Before you use the instrument for the first
time, please read the instructions in detail, which will help you to use the instrument
skillfully.
Our aim is to continuously improve and improve the
company's products, so the instruments you use may be
slightly different from the instructions. If there are any
changes, we will use the attached page to inform you, please
forgive me! If you have any ambiguities, please contact our
after-sales service department. We will meet your
requirements.
As the input and output terminals, test columns and so
on are possible with voltage, when you plug and unplug the
test line, power socket, will produce electric spark, be
careful of electric shock, avoid electric shock danger, pay
attention to personal safety!
Solemn commitment
The products manufactured by the company shall be
replaced within three months from the date of shipment in case of any defect. Within one
year (including one year) if the product defects, implementation of free maintenance. If the
product is defective for more than one year, it will be repaired for long-life with paid
service.
Safety requirements
Please read the following safety precautions to avoid personal injury and to prevent
damage to this product or any other products connected with it. In order to avoid possible
risks, this product can only be used within the prescribed scope.
Only qualified technicians can perform maintenance.
- Preventing fire or personal injury

7
Use appropriate power cords. Only use the power cord which is special for this
product and conforms to the specification of this product.
Connect and disconnect correctly. When the test wire is connected to the live
terminal, do not connect or disconnect the test wire at will.
Product grounding. In addition to grounding through the power line grounding wire, the
grounding column of the product housing must be grounded. To prevent electric shock,
ground conductors must be connected to the ground. Ensure that the product is properly
grounded before connecting to the input or output terminals of the product.
Note all terminal ratings. In case of fire or electric shock hazard, please note all
ratings and markings of this product. Before connecting to this product, please read the
product manual for further information about the rating.
Do not operate without instrument cover. Do not operate the product if the cover or
panel has been removed.
Use proper fuses. Only use fuses that conform to the specified type and rating of this
product.
Avoid contact with exposed circuit and live metal. Do not touch the exposed
contacts and parts when the product is energized.
Do not operate in case of suspicious failure. If the product is suspected to be
damaged, please check the company's maintenance personnel, do not continue to
operate.
Do not operate in damp environment.
Do not operate in explosive environment.
Keep product surface clean and dry.
－Security term
Warning: a warning indicates a condition or practice that may result in personal injury or
death.
Caution: The word "caution" refers to the condition or practice that may cause damage to
the product.

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I. Product Overview
This series of control boxes are designed and manufactured according to the unique
usage range of high voltage test transformers. Their functions are as follows:
A. Overcurrent protection
B. Timing sound and light alarm;
C. Direct reading of high voltage voltage;
D. Free Setting of Voltage Test Time (Digital Display)
E. Mobile structure (desktop)
II. Working Principle
This series of control boxes are composed of contact voltage regulator (more than
50KA is electric column voltage regulator) and its control, protection, measurement and
signal circuits. It adjusts the voltage regulator (i.e. the input voltage of the test transformer)
by connecting 220V or 380V power frequency power supply to obtain the required test
high voltage voltage value. Its working principle is shown in Fig. 1:
Figure 1: Working Principle of Control Box
BH-Current transformer Α -Ammeter
KV -High Voltage Display Meter T-Voltage regulator

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III. Technical Parameters,Specifications and Selection
and Matching
The capacity of the control box is nominated as the capacity of the voltage regulator
and the voltage regulator. If it works with the test transformer (working system within 30
minutes in a short time), it can be matched according to the provisions of the power
industry standard of the People's Republic of China "DL474.4-92": P=0.75P. P-test
transformer capacity and P-regulator capacity. If it is used for batch test of electrical
equipment factory products, the capacity of voltage regulator should be equal to the
capacity of test transformer, that is,P0=P.
The technical parameters of the control box are shown in Table 1.
1. Rated capacity：10kVA
2. Input voltage：220V
3. Input current：45.5A
4. Output voltage：0-250V
5. Weight：30kg
6. Dimensions：400X320X390（mm）
IV. Operational Guidelines
Before operation, the maximum working current should be calculated and the current
protector should be adjusted according to the capacity and voltage level of different
subjects. The test wiring should refer to Figure 1 of this specification or the related
connection schematic diagram of the test transformer, and the grounding end should be
well grounded (as shown in the following voltage withstand test for example).
1. Connect the power supply (box type is socket type power supply, desk type is
connection pole type power supply), and auto-buck voltage regulator to zero position, zero
switch closed, zero position indicator light (red light) on (also known as zero output state
indicator of voltage regulator);
2. Press the start button (green), the contactor is sucked in, the voltage regulator is
electrified, and the working indicator (green light) is on.
3. When the main circuit starts to supply electricity, press the boost button to rotate the

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regulator clockwise and evenly, and the voltage output is provided by the voltage regulator.
And closely watch the meter reading, when the required high voltage value is raised,
press the drop voltage, and press the timing button (yellow) in time. At this time, the digital
display time relay timing display time (time unit is "s", seconds). When the time arrives, the
control box (platform) sends out sound and light alarm, and rotates the regulator handle in
reverse direction in time until the regulator returns to zero. Up to now, release the timer
button;
4. In the process of boost or withstand voltage test, if there is over current such as
short circuit, flash-over and breakdown, the current relay protection trips and the voltage
regulator automatically turns off, indicating that the tested product is unqualified. At this
time, the voltage regulator should be returned to zero, the power supply should be cut off
and the tested product should be checked.
V. Use and Maintenance
1. When checking and accepting the open box, check whether the main control circuit
wiring is loose and whether the voltage regulator brushes are in good contact.
2. When not in use for a long time, 500 V Megohmeter is used to measure insulation
resistance before use, and its resistance value is not less than 0.5 M.
3. The power supply voltage shall conform to the input voltage value on the nameplate of
the box.
4. The box is equipped with over-current protection and has been adjusted to 80% of the
rated current. When used for small load, it should be reset according to the rated capacity
current of the tested product.
5. After use, the door cover should be closed to keep the inside of the box clean.
VI. Conditions of Use
1. Environmental temperature: 0-40℃;
2. Altitude: ＜1000 m;
3. Relative humidity: ＜85%;
4. There should be no gas, steam, chemical dust and other explosive and corrosive media
that seriously affect the insulation in the workplace.

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Packing List
No.
Item
Qty
1
Booster
1
2
Control box
1
3
Power line
1
4
Test line
1
5
Silicon heap
1