Datasheet
Table Of Contents
- Overview
- Applications
- Benefits
- Part Number System
- Performance Characteristics
- Surge Voltage
- Test Method & Performance
- Dimensions – Millimeters
- Dimensions – Inches
- Termination Tables
- Shelf Life
- Re-Age (Reforming) Procedure
- Reliability
- Failure Rate
- Environmental Compliance
- Table 1 – Ratings & Part Number Reference
- Mechanical Data
- Marking
- Construction
- Construction Data
- KEMET Electronics Corporation Sales Offices
- Disclaimer
13© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard A4075_ALS70_71 • 7/15/2020
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
Screw Terminal Aluminum Electrolytic Capacitors – ALS70/71, High CV, +85°C
Mechanical Data
Polarity and Reversed Voltage
Aluminium Electrolytic capacitors manufactured for the use in DC applications contain an anode foil and a cathode foil. As
such, they are polarized devices and must be connected with the +ve to the anode foil and the -ve to the cathode foil. If this
were to be reversed, then the electrolytic process that took place in forming the oxide layer on the anode would be recreated
in trying to form an oxide layer on the cathode. In forming the cathode foil in this way, heat would be generated and gas
would be given off within the capacitor, usually leading to a catastrophic failure.
The cathode foil already possesses a thin stabilized oxide layer. This thin oxide layer is equivalent to a forming voltage
of approximately 2 V. As a result, the capacitor can withstand a voltage reversal of up to 2 V for short periods. Above this
voltage, the formation process will commence. Aluminium Electrolytic capacitors can also be manufactured for the use in
intermittent AC applications by using two anode foils in place of one anode and one cathode.
Mounting Position
The capacitor can be mounted in any position as long as the safety vent can operate. It is possible for some electrolyte to be
expelled. As this is a conducting liquid, suitable precautions should be initiated by the system designer to avoid secondary
short circuits.
The capacitors are designed to be mounted in free air and are not suitable for submersion in liquid.
Insulating Resistance
≥ 100 MΩ at 100 VDC across insulating sleeve.
Voltage Proof
≥ 3,500 VDC across insulating Sleeve
≥ 2,500 VAC across insulating Sleeve
Safety Vent
A safety vent for overpressure is featured on the terminal deck in the form of a rubber plug, designed to relieve build-up of
internal pressure due to overstress or catastrophic failure.