6

ELECTROLYTIC ALUMINUM CAPACITORS

Revision 01/19

www.exxelia.com

Tel : + 33 (0)2 40 01 26 51

ELECTROLYTIC ALUMINUM CAPACITORS

6

Revision 01/19

www.exxelia.com

Tel : + 33 (0)2 40 01 26 51

1. BASIC CONSTRUCTION

Structure of an electrolytic aluminum capacitor is shown hereunder:

1. Anode: aluminum foil

2. Dielectric: aluminum oxide

3. Papers spacers impregnated with electrolyte

4. Ionic conduction assumed by electrolyte

5. Cathode: aluminum foil

The positive plate is an etched aluminum foil covered with alumina

which is the dielectric of the capacitor.

The negative plate is constituted by a second aluminum foil which

serves as a current supply, and by electrolyte-impregnated papers

layers.

The metal used for anode is a ≥ 99,98 % grade aluminum.

The dielectric has a thickness of 13 Å / V.

The aluminum used for the cathode is a ≥ 98 % grade aluminum

covered with a dielectric layer with a thickness of about 40 Å.

2. DIAGRAM OF THE EQUIVALENT CIRCUIT

CA = Capacitance of the anode

CK = Capacitance of the cathode

Rp = Parallel resistance due to the aluminum oxide f Ilms.

RL = Series resistance of connections, plates and impregnated

spacer.

Ls = Inductance of winding and connections.

A standard simplified diagram is.

Cs is the series capacitance of both anode and cathode capacitances.

Electrolytic aluminum capacitors are naturally polarized because

of the insulating f Ilm on the anode. Given the very thin aluminum

oxide layer, a reversed voltage should not exceed 1.5 V when there is

energy supply.

Short duration reverse voltages can be absorbed by special

construction, second anode replacing the former cathode.

3. CAPACITORS MARKING

3.1. ARTICLE CODE (ON EACH PACKAGING)

Afollowedby6figuresnumber.First3positionsarespecificoftherange.

(Ex. A 745xxx for a FELSIC 85 BD)

In FELSIC ranges, article code without first letter A, is printed on each

capacitor.

a Figure 9 in fourth position shows a special product.

3.2. BATCH (ON EACH CAPACITOR).

3 figures or 6 figures

3.3. DATE (ON EACH CAPACITOR IF APPLICABLE)

4 figures (year-week)

4. ELECTRICAL CHARACTERISTICS

4.1. RATED CAPACITANCE CR

The rated capacitance is defined at 100 Hz and at ambient

temperature.

4.2. RATED VOLTAGE UR

UR is the maximum DC voltage which may be applied in continuous

operation.

When applying a superimposed alternating voltage, the peak value of

the resulting waveform should not exceed the rated voltage.

4.3. PEAK VOLTAGE UP

Up is the maximum repetitive voltage which can be applied within

short periods.

Defined in CECC 30 300 and IEC 60 384-4:

1000 cycles of 30 s charge followed by a no load period of 5 min. 30 s

with upper category temperature.

Up ≤ 1,15 UR (UR ≤ 315 V)

Up ≤ 1,10 UR (UR > 315 V)

General technical data

140 FELSIC in bank

701 PRORELSIC 125

703 PRORELSIC 125

704 SNAPSIC

705 SNAPSIC 105

706 FELSIC HP BC – BD

708 PRORELSIC 145

710 CUBISIC

711 PROMISIC 031

712 CUBISIC LP

713 SNAPSIC 105 LP

714 SNAPSIC 4P

715 SNAPSIC 105 4P

716 SNAPSIC HV

717 SNAPSIC HC

718 SNAPSIC 125

721 RELSIC 033

722 CI FRS

723 CI FRS

728 FELSIC 039 (ex 727)

FELSIC DI

738 FELSIC 037 (ex 737)

740 FELSIC 125 FRS BC

(ex 731)

741 FELSIC 125 FRS BD

(ex 731)

742 PRORELSIC 105 TFRS

743 PRORELSIC 105 TFRS

744 FELSIC 85 BC

FELSIC 85 LP

745 FELSIC 85 BD

746 FELSIC 85 M BC

747 FELSIC 85 M BD

748 SICAL CO 42 - SICAL

749 SICAL CO 42 - SICAL

750 CUBISIC 125

756 FELSIC 105 BC

FELSIC 105 LP

757 FELSIC 105 BD

760 FELSIC HC BC

761 FELSIC HC BD

762 FELSIC 105 TFRS BC

763 FELSIC 105 TFRS BD

764 FELSIC HV BC

765 FELSIC HV BD

775 VACSIC

774 VACSIC 150

776 ALSIC 20G

ALSIC 145 20G