There Are Four Commonly Used Detection Methods For The Output Voltage Of The Withstand Voltage Tester, Including The Electrostatic Voltmeter Method, The Voltage Transformer Method, The Voltage Divider With A Voltmeter Method, The High Resistance Box With A Milliamp Meter Method, And The DBNY-S Withstand Voltage Test Developed By Dingsheng Power The Instrument Is Mainly Used To Inspect The Withstand Voltage Capabilities Of Various Electrical Equipment, Insulating Materials And Insulating Structures. The Withstand Voltage Tester Can Adjust The Size Of The Test Voltage And Set The Breakdown Current. This Article Recommends Several Output Voltage Detection Methods Based On The Skill Requirements Of The Verification Regulations.
4 Detection Methods For The Output Voltage Of The Withstand Voltage Tester
1. Electrostatic Voltmeter Method
2. Voltage Transformer Method
Three, Voltage Divider With Voltmeter Method
Four, High Resistance Box With Milliameter Method
According To The Above 4 Methods And Ideas, The Detection System Composed Of The Standard Device And The Self-Denial Voltage Divider Should Be Selected, And The Faults Should Be Summarized To Meet The Requirements Of The Verification Regulations. In Addition, The Standards Of The Withstand Voltage Tester (Equipment) Are Complicated, And The Measurement Methods Of Its High Voltage Output Are Not Limited To The Above Four. Only On The Basis Of The Applicable Scope And Technical Policies Of The Current Verification Regulations, The Useful Methods And Basic Principles Of Output Voltage Detection Are Introduced For The Reference Of Relevant Personnel.
1. Withstand Voltage Tester
Withstand Voltage Tester Is Also Called Electrical Insulation Strength Tester Or Dielectric Strength Tester. A Regular Communication Or DC High Voltage Is Applied Between The Live Part Of The Electrical Appliance And The Non-Charged Part (Usually The Shell) To Check The Voltage Resistance Of The Electrical Insulation Material. During Long-Term Operation Of Electrical Appliances, Not Only Need To Accept The Effect Of Additional Operating Voltage, But Also Accept The Effect Of Overvoltage That Is Higher Than The Additional Operating Voltage For A Short Time During The Operation (The Overvoltage Value May Be Several Times Higher Than The Value Of The Additional Operating Voltage. ). Under The Effect Of These Voltages, The Internal Structure Of Electrical Insulating Materials Will Change. When The Overvoltage Intensity Reaches A Certain Value, The Insulation Of The Material Will Be Broken Down, The Electrical Appliance Will Not Work Normally, And The Operator May Get An Electric Shock, Endangering Personal Safety.
1. Structure And Composition Of Withstand Voltage Tester
(1) Boosting Part
It Is Composed Of Voltage Regulating Transformer, Step-Up Transformer And Step-Up Part Power Supply And Blocking Switch.
The 220V Voltage Is Turned On And The Blocking Switch Is Added To The Regulating Transformer And The Regulating Transformer Output Is Connected To The Boosting Transformer. Users Only Need To Dispatch The Voltage Regulator To Control The Output Voltage Of The Step-Up Transformer.
(2) Control Part
Current Sampling, Time Circuit And Alarm Circuit. When The Control Part Receives The Start Signal, The Instrument Is Immediately Turning On The Boost Part Power Supply. When The Measured Circuit Current Exceeds The Set Value And An Audible And Visual Alarm Is Received, The Boost Circuit Power Supply Is Immediately Blocked. Block The Boost Loop Power Supply After Receiving The Reset Or Time Up Signal.
(3) Flash Circuit
The Flasher Flashes The Output Voltage Value Of The Step-Up Transformer. The Current Value Of The Current Sampling Part And The Time Value Of The Time Circuit Are Generally Counted Down.
(4) The Above Is The Structure Of The Traditional Withstand Voltage Tester. With Electronic Technology And Single Chip, Computer Technology Has Been Developed Rapidly; Program-Controlled Voltage Withstand Tester Has Also Been Developed Rapidly In Recent Years. The Difference Between Program-Controlled Voltage Withstand Tester And Traditional Withstand Voltage Tester Is Mainly The Boost Part. The High-Voltage Boost Of The Programmable Withstand Voltage Meter Is Not Dispatched By The Voltage Regulator Through The Mains, But A 50Hz Or 60Hz Sine Wave Signal Is Generated Through The Control Of The Single-Chip Computer And Then Expanded And Boosted By The Power Expansion Circuit, And The Output Voltage Value Is Also Controlled By The Single It Is Controlled By A Chip Computer, And Other Parts Of The Principle Are Not Much Different From The Traditional Pressure Tester.
2. Selection Of Withstand Voltage Tester
The Most Important Thing In Choosing A Withstand Voltage Meter Is Two Policies. The Maximum Output Voltage Value And Maximum Alarm Current Value Must Be Greater Than The Voltage Value And Alarm Current Value You Need. Generally, The Standard Of The Tested Product Stipulates The Application Of High Voltage And The Alarm To Determine The Current Value. Assuming That The Higher The Applied Voltage, The Greater The Alarm Current, The Higher The Power Of The Step-Up Transformer Of The Withstand Voltage Meter Is Required. Generally, The Power Of The Step-Up Transformer Of The Withstand Voltage Meter Is 0.2kVA, 0.5kVA, 1kVA, 2kVA, 3kVA, Etc. The Highest Voltage Can Reach Tens Of Thousands Of Volts. The Maximum Alarm Current Is 500mA-1000mA, Etc. Therefore, These Two Policies Must Be Paid Attention To When Choosing A Pressure Tester. If The Power Is Too Large, It Will Be Spoiled. If The Power Is Too Small, The Withstand Voltage Test Cannot Correctly Judge Whether It Is Qualified Or Not. According To The Rules In IEC414 Or (GB6738-86), We Think It Is More Scientific To Select The Power Method Of The Withstand Voltage Meter. “First, Adjust The Output Voltage Of The Withstand Voltage Meter To 50% Of The Regulated Value, And Then Connect The Tested Product. When The Observed Voltage Drop Is Less Than 10% Of The Voltage Value, It Is Assumed That The Power Of The Withstand Voltage Meter Is Satisfactory. “That Is, Assuming That The Voltage Value Of The Withstand Voltage Test Of A Certain Product Is 3000 Volts, First Adjust The Output Voltage Of The Withstand Voltage Meter To 1500 Volts And Then Connect The Tested Product. It Is Assumed That The Value Of The Output Voltage Drop Of The Withstand Voltage Meter At This Time Is Not Greater Than 150 Volts, Then The Power Of The Withstand Voltage Meter Is Sufficient. There Is Distributed Capacitance Between The Live Part Of The Test Product And The Shell. The Capacitor Has A CX Capacitive Reactance, And When A Communication Voltage Is Applied To Both Ends Of The CX Capacitor, A Current Will Be Drawn.
Post time: Feb-06-2021
