D75/44.4 MOV varistor for surge arrester

Zinc Oxide Varistor

Zinc Oxide Varistor is widely used in large filed of lightening protection,they are specified according to the voltage range that they can tolerate without damage. Other important parameters are the varistor's energy rating in joules, operating voltage, response time, maximum current, and breakdown (clamping) voltage. Energy rating is often defined using standardized transients such as 8/20 microseconds or 10/1000 microseconds, where 8 microseconds is the transient's front time and 20 microseconds is the time to half value.

The Parameters of the products

ROUTINE PRODUCTION TESTS

Tests on all MOV disks To insure product conformance, the following Routine

Production Tests were performed on every MOV Disk:

1. Double Long Duration Current Test. Two shots of 190A during 2ms are applied to the

disk to assure the structural strength of the block.

2. Reference Voltage Test. Voltage Uf at 1mA . DC Voltage is applied to the disk and the current ismeasured. The voltage is increased until the DC current reaches 1mA.

3. Physical Inspection. Each disk is physically inspected for any flaws created during

manufacture or testing.

LOT RELEASE TESTS

Quality Assurance lot release tests disks to insure product conformance, the

following Routine Quality Assurance Tests were performed on every lot of MOV

Disks. These tests are performed on a sample basis for all MOV disk lots.

1. High Current Durability Test A representative sample from each manufacturing lot must pass two consecutive 100 kA, 4/10 μs current impulses and remain thermally stable.

2. Thermal Stability Test A representative sample from each manufacturing lot is heated

to 150°C and energized at U c* and power losses are recorded and compared to factory

limits for10 minutes.

3. Nonlinearitv Test A representative sample of each lot receives impulses of 3, 5 and 10

kA using an 8/20 ms current waveform. Discharge voltage curve flatness is measured to

ensure compliance with published maximum discharge voltage curve.

100% of all disks rnanufactured are required to pass the routine and Quality Assurance,

lot qualification tests prior to packaging.

ELECTRICAL SPECIFICATIONS AND ACCEPTANCE CRITERIA

Typical factory limits 10kA MOV blocks are internally established to commit the following values.

Parameter                        Condition             Limit

Reference Voltage, Uf      @5mApeak           >3.36 kVrms

Reference Voltage, Uf      @5mApeak           >4.75 kVpeak

Reference Voltage, Uf      @1mAdc            >4.45 kV

Residual Voltage, Us               @5kApeak           <9.20 kVpeak

Residual Voltage, Us               @10kApeak         <9.80 kVpeak

MCOV, W losses             @2.55kV           <0.4 W

 Type of the box :

The Package details

The Parameters of the Pallets

Real Packaging Photos

The Real Pallets Photos