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Application notes for type A capacitors.

Type A capacitors do not have a specific failsafe device as specified in the applicable standards for type B- or P2-capacitors. In the event of failure the winding element may overheat rapidly and melt, smoke and even ignite; melted material may drip from the capacitor as well. It is therefore necessary to undertake proper measures to provide reliable safety for people and property when using type A capacitors. The recommendations of the German Association of the Electrical Industry (ZVEI) for the use of type A lighting capacitors say: Type A capacitors may be used in luminaires only where the capacitor is allocated (1) in uncritical environment (non-inflammable materials). In its Guidelines for the Prevention of Damage Caused by Luminaires, the Association of German Property Insurers - VdS - demands: Capacitors without overpressure break-action mechanism must be encapsulated in a metal case which prevents the ignition of inflammable materials in their (2) surroundings. Only capacitors with break-action mechanism are suitable for use in sensitive environment. In case of doubt regarding the character of the ambient conditions our capacitors with break-action mechanism should be given preference.

It is the capacitor manufacturers' responsibility to draw attention to the risks and special considerations necessary when unprotected capacitors are employed.

It is the lighting manufacturers' responsibility to ensure that the risks that are always present in a technical system are kept within acceptable limits by suitable lighting design and capacitor selection, while complying with all conditions and directives.

WE CANNOT BEAR THE LIABILITY FOR DAMAGE IS CAUSED BY THE PARTICULAR NATURE OF UNPROTECTED CAPACITORS UNSUITABLE LUMMINAIRE DESIGN OR THE INCORRECT APPLICATION OF LUMINAIRES.

Safety Notice

AC - Capacitors for Motors and Fluorescent Lamps

Compensating capacitors in MKP-technology are AC capacitors designed for individual correction of the power factor of transformers and magnetic ballasts in discharge lamps (e.g. fluorescent lamps, halogen and metal vapour lamps, high-pressure mercury vapour lamps, sodium lamps) in mains with a frequency of 50 or 60Hz. This allows for an improvement of the luminary's power factor to cosφ ≥A0.9.

Capacitors for motor run applications are AC capacitors designed for the operation of induction motors on single phase mains supplies.

These capacitors may also be used in any case of power factor correction. Thanks to their very low loss level, they can also be used for applications in energy electronics, provided the specified operating conditions and permissible loads are not exceeded.

General Data

Construction
All capacitors listed in this catalogue are manufactured in MKP technology; they contain a low-loss dielectric formed by pure polypropylene film. A thin self-healing mixture of zinc and aluminium is metallized directly on one side of the PP-film under vacuum. The plastic film is wound into stable cylindrical windings. The ends of the capacitor windings are contacted by spraying with a metal contact layer, facilitating a high current load and ensuring a low-inductance connection between the terminals and windings. After insertion into the capacitor case, resin or oil is introduced for all capacitors with voltage ratings of 280V and above. This protects the winding from environmental influence and provides a long life-expectancy and stable capacitance.

• Note: All MKP capacitors made by DNA are free of PCB or any other form of toxic impregnant.

Safety against Over-voltages and Short Circuits

Self-healing dielectric
All capacitors are "self-healing": In the event of a voltage breakdown in the dielectric the metal layers around the breakdown channel are evaporated by the temperature of the electric arc that forms between the electrodes. They are removed within a few microseconds and pushed apart by the overpressure generated in the centre of the breakdown spot. An insulation area is formed which is reliably resistive and voltage proof for all operating requirements of the capacitor. The capacitor remains fully functional during and after the breakdown.

During the service life of the capacitor, especially under conditions of permanent overload, the ability of the dielectric to regenerate (self-healing) may deteriorate. As a result, the risk of a non-healing breakdown with continuous short circuit may occur. "Self-healing dielectric" must therefore not be mistaken for "fail-safe".

Over-pressure protection (FPU): the Break-Action Mechanism (Type B/Class P2 capacitors)

Self-healing capacitors do not have to be separately fused against short circuits as they regenerate themselves after breakdowns of the dielectric. In the event of over-voltage or ageing at the end of the capacitor's useful service life, an increasing number of self-healing breakdowns may cause rising pressure inside the capacitor. To prevent them from bursting, hermetically sealed capacitors can be fitted with a "break action mechanism". This safety mechanism is based on an attenuated spot at one of the connecting wires inside the capacitor. With rising pressure the casing begins to expand, mainly by opening the folded crimp and pushing the lid upwards. As a result, the prepared connecting wire is separated at the attenuated spot, and the current path is interrupted irreversibly.

Temperature Fuse (type A capacitors)

For lighting capacitors without over-pressure protection, DNA can offer a thermal fuse which is integrated in the capacitor core and which responds to over-temperatures caused by electrical or thermal overload. The fuse element within the body melts when a critical temperature is reached. It melts into small open globules which are completely insulated from each other not only by the distance but also by a special insulating compound which appears at the point of meltdown. The thermal disconnection is resistant to surge currents within the permitted range of capacitor current.

95% of all critical capacitor failures are accompanied by a gradual increase of the loss power. As any increase of the loss power always leads to a temperature rise inside the winding element, the temperature fuse offers efficient protection for most of the critical capacitor failure scenarios. However, type A capacitors with temperature fuse can neither provide the kind of full protection offered by capacitors in aluminium can with break-action mechanism, nor can they fulfil the test requirements for such capacitors.

Important remarks on the safety of Type A and P0 capacitors

Type A capacitors do not have a specific failsafe device as specified in the applicable standards for type B- or P2-capacitors. In the event of failure the winding element may overheat rapidly and melt, smoke and even ignite; melted material may drip from the capacitor as well. It is therefore necessary to undertake proper measures to provide reliable safety for people and property when using type A capacitors. The recommendations of the German Association of the Electrical Industry (ZVEI) for the use of type A lighting capacitors say: Type A capacitors may be used in luminaires only where the capacitor is allocated (1) in uncritical environment (non-inflammable materials). In its Guidelines for the Prevention of Damage Caused by Luminaires, the Association of German Property Insurers - VdS - demands: Capacitors without overpressure break-action mechanism must be encapsulated in a metal case which prevents the ignition of inflammable materials in their (2) surroundings. Only capacitors with break-action mechanism are suitable for use in sensitive environment. In case of doubt regarding the character of the ambient conditions our capacitors with break-action mechanism should be given preference.

Mounting and Operating Instructions
1. Connection and fixation

The capacitors are fixed by an M8 or M12 bottom screw. For lighting capacitors in plastic can an alternative fixation with side clip is available.

The following kinds of connection are available as standard.

Solder lug 3 mm
- type R acc. to DIN 41 496 (for connecting wires up to 1.5mm²) tab connector 2.8 mm
- type A acc. to DIN 46 244 part 1 tab connector 6.3 mm
- type A acc. to DIN 46 244 part 1 dual tab connector 6.3mm
- type A acc. to DIN 46 244 part 1

Push wire terminal
- capacitor terminal type with internal discharge resistor, suitable for currents of up to 10A and connecting wires of 0.5 mm²...1.5 mm²

Wires
- 200 mm, 0.5-0.75 mm²

Cable
- Hose line 250 mm, 0.75 mm²

Make sure to use connecting wires or cables of sufficient length and flexibility when connecting capacitors with break-action mechanism in order not to prevent the mechanism from expansion in the event of capacitor failure.

The hermetic sealing of the capacitors is extremely important for a long operating life and for the correct functioning of the beak action mechanism. Please pay special attention not to damage the rubber seal and the soldering at the bottom of the tab connectors.

2. Mounting Position/Distance to Other Components

All capacitors can be mounted without restrictions in any position. A clearance of at least 10mm above the terminals shall be accommodated for capacitors with break-action mechanism.

Capacitors shall not be mounted in the close vicinity of heat, light or heat convection sources (such as conventional ballasts, lamps, heating spirals, etc.); high temperatures as well as steady UV-radiation may cause premature ageing. Capacitors without filling should not be mounted directly on vibration sources (such as motors, ventilators, gear boxes, etc.).

3. Operating voltage

The capacitors have been designed for continuous operation at the rated voltage stated on the label; the related voltage can be exceeded within the limits permitted by applicable standards only:

1.1 x Un

8 h/d

1.15 x Un

30 min/d

1.2 x Un

5 min/d

1.3 x Un

1 min/d

Subject to inductive components within the capacitor circuit, lighting capacitors connected in series with the ballast as well as motor run capacitors are exposed to voltages which permanently exceed the rated mains voltage. This, and the tolerances of all elements in the circuit as well as their drift due to ageing effects, has to be considered when designing the application and determining the proper capacitor value.

4. Operating temperature

The temperature limits stated in the data charts are relating to the permissible temperature at the surface of the capacitor case. They are not identical with the ambient temperature as the capacitors' self-generated dissipation heat during operation must be taken into consideration as well.

5. Condensation, Humidity

Condensation on the capacitors is not permitted. The permissible humidity class and climatic category of the capacitors are stated in the data charts. The mentioned limit values for humidity must not be exceeded even during storage.

6. Service Life

The following data is based on empirical experience; in accordance with applicable standards, the stated operating life allows for a limited degradation of the capacitance (depending on type, between 3 and 10%) and a failure rate of up to 3%.

Over-temperatures, over-voltages, harmonic distortion and excessive humidity may reduce the service life expectancy or cause increased failure rates.

Lighting Capacitors

Capacitor

Service Life

parallel capacitors with break-action mechanism

ca. 75,000h

parallel capacitors without break-action mechanism in plastic or aluminium can

ca. 50,000h

series capacitors with break-action mechanism

ca. 50,000h

Motor-run Capacitors

Application Class

Service Life

A

30,000h

B

10,000h

C

3,000h

D

1,000h

7. Disposal

Our capacitors do not contain PCB, solvents, or any other toxic or banned materials. The impregnants and filling materials contain vegetable oil or polyurethane mixtures.
The capacitors are not rated as hazardous goods in transit and do not have to be marked under the Regulations for Hazardous Goods. They are rated WGK 0 (water risk
category 0 "no general threat to water").

We recommend disposing of the capacitors through professional recycling centres for electric/electronic waste.

The capacitors can be disposed of as follows:

• Capacitors: acc. to European Waste Catalogue (EWC) No. 160216 ("Components taken from discarded equipment")
• Liquid filling materials: acc. to EWC No. 080402 ("Waste adhesives and sealants free of halogenated solvents")
• Hardened filling materials: acc. to EWC No. 080404 ("Hardened adhesives and sealants").

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