omjbfl1

Rectangle

The tests described below are the most important for EMI capacitors.

test Publication Procedure requirements

impulse EN/IEC 60384-14: According to fig. 1 No permanent breakdownvoltage 2005 Before Endurance or flashover

Endurance EN/IEC 60384-14: According to fig. 2 Voltage proof 2005 with U2 = 1000 VAC C, DF and Insulation X: U1 = 1.25 x UR VAC Y: U1 = 1.7 x UR VAC

vibration IEC 60068-2-6 3 directions No visible damage Test Fc at 2 hours each No open or 10 – 500 Hz at short circuit 0.75 mm or 98 m/s2

Bump IEC 60068-2-29 4000 bumps at No visible damage Test Eb 390 m/s2 No open or short circuit

change of IEC 60068-2-14 Upper and lower No visible damagetemperature Test Na rated temperature 5 cycles

solderability IEC 60068-2-20 Solder globule Wetting time Test Ta method for d ≤ 0.8 < 1s for d > 0.8 < 1.5s

Passive EN/IEC 60384-14: Flame exposure time 3, 10 or 30 s burning time flammability 2005 depending on severity depending on flammability class

active EN/IEC 60384-14: Surge pulses Ui + UR AC No flameflammability 2005 (Fig 3.)

humidity IEC 60068-2-3 + 40°C and 21 or 56 days Test Ca 90 – 95% R.H.

U

UiUR

time

impulse voltage test (fig. 1)According to EN/IEC 60384-14:2005

Capacitor class Up kV

X1 4 X2 2.5 X3 none Y1 8 Y2 5 Y3 none Y4 2.5

Fig. 1

Endurance test (fig. 2)According to EN/IEC 60384-14:2005Fig. 2

active flammability (fig. 3)According to EN/IEC 60384-14:2005UR VAC is connected to the capacitor. With an interval of 5 s, 20 pulses (Ui ) are placed on the capacitor. The capacitor may not burn.

Capacitor class Ui kV

Y2 5X1 4X2, Y3, Y4 2.5X3 1.2Y1 not tested

Fig. 3

0.1 sec

each hour

U2 U1

Vrms

Up

Up__2

1.2 50

timeµs

quaLitY tEsts and REquiREmEnts

Emi suPPrEssors

BasiC dEsign

The capacitor consists of a winding which, for a single layer capacitor, comprises two strips of metallized dielectric. On the metallized dielectric a margin is left on one side, and the strips are so arranged, that the metal coating on one strip extends to one edge of the finished winding, and the metal coating on the next strip extends to the other edge.

Connections to the electrodes are made by spraying a layer of metal on the ends of the winding, to which the terminating wires can subsequently be attached by welding or soldering.

During manufacture the capacitor is connected to a DC supply to clear the metal layer around pin-holes and other weak spots in the dielectric to ensure a high and stable insulation in the capacitor. To meet high voltage and safety demands some capacitors have a series winding construction.

In metallized paper capacitors intended for higher voltages one

electrodefree margin

dielectric

SINGLE LAYER

MULTILAYER (MP)

electrodefree margin

dielectric

center margin

Metallized Film CapacitorSingle Design

Metallized Film CapacitorSeries Design

Metallized Film CapacitorTriple Design

or more layers of plain paper are inserted between the metallized papers to reinforce the dielectric (multi-layer). The MP winding is impregnated with epoxy resin in vacuum.