MB Protected

Application: General purpose, mainly for single phase AC loads such as fans, coolers, washing machines and other small appliances.

Available in Matchbox type. Made of ABS material, with and without mounting ear.
UL Approved: 
Available in Matchbox type. Made of flame retardant thermoplastic material meeting flammability UL 94-V2, with and without a mounting ear.

Encapsulation: Dry Filling Materials (Encapsulated in non-PCB resin)

Capacitance Tolerances:  For Less than and equal to 400V: ±10%
For greater than 400V: ±5%
(For other, please inquire).

Conforming to: IEC 60252-1 (2013-08), VDE 0560-8, JIS C-4908, ISO9001:2015, UL810.

Raw Material Conforming to:  IEC-60227, JISC-2330.

Rated Voltage*:  250V to 520 V (for other, please inquire).

Protection Class:  S3

Why MB Protected S3 capacitors: 

A safety listing is not required for motor run capacitors under IEC 60252-1 but listing for a(P-2 used in old standards for all protected capacitors, now S2 is used for pressure interrupter and S3 for segmented film capacitors) S3 motor run capacitor requires an interrupter system by segmented film ensuring the capacitor fails in an open condition in the event of a capacitor failure. Otherscapacitors, listed as (P0,P1) S0 and S1 may or may not fail in an open condition.

For film capacitors with very high standards for stability and long lifetime, such as S3 capacitors, the metallization can be made with a special fault isolation pattern. Such a metallization formed into patterns. Each of these patterns” produces a deliberately narrowed cross-section in the conductive metallization. These restrictions work like microscopic fuses so that if a point-defect short circuit between the electrodes occurs, the high current of the short only burns out the fuses around the fault. The affected sections are thus disconnected and isolated in a controlled manner, without any explosions surrounding a larger short-circuit arc. Therefore, the area affected is limited and the fault is gently controlled, significantly reducing internal damage to the capacitor, which can thus remain in service with only an infinitesimal reduction in capacitance.

APPLICATION: General purpose for single phase AC loads such as fans, washing machines and other small appliances.

CONSTRUCTION: The capacitor elements are formed by winding low loss, self-healing, and segmented metalized polypropylene film on mandrels. Different types of film patterns are used for the manufacturing of capacitor elements in order to assure that the capacitor may or may not fail in an open condition. High speed computerized winding machines are used for this purpose. Subsequently, the windings are compressed to expel air from the windings. Capacitors are made up of UL approved components with flame retardant filling resins and container.

UL Approved: 
Available in Matchbox type. Made of flame retardant thermoplastic material meeting flammability UL 94-V2, with and without a mounting ear.

ENCAPSULATION: Dry Flame Retardant Filling Materials (Encapsulated in non-PCB resin).


SERIES MB (Protected – S3) made up of segmented type MPP film
Without Mounting Ear: MBNL, MBNW.
STANDARD IEC 60252-I (2013-08), JIS C-4908, ISO 9001:2015 (For UL Approved, UL810).
CLASS A (30,000 hrs).
TERMINATION Various Details, For different subseries, termination details are different.
FIXING Mounting ear of 4.5mm dia.
Without mounting ear also available.
CAPACITANCE TOLERANCE For Less than and equal to 400V: ±10%
For greater than 400V: ±5%
(For other, please inquire)
RATED VOLTS 250V to 520V (for other, please inquire)
RATED CASE TEMPERATURE -25ºC/+85ºC (As per IEC 60252-1)
DISSIPATION FACTOR For Less than 10µF: ≤0.0010
For greater than equal to 10µF:≤0.0020
TEST BETWEEN TERMINALS 2 x Rated volts for 2 Sec (Routine Test)
2 x Rated Volts for 60 Sec (Type Test)
RELAIBILITY TEST 1.4 x Rated Volts for 100,000 Cycles (Duty cycle: 2 Sec ON & 2 Sec OFF) as per JIS C-4908
1.3 x Rated volts for 3,000 hrs (Continuous voltage application) as per IEC 60252-1

Precautions and Life of S3 Technology

The common MPP films are limited only to covering the total surface or to varying the thickness of metallization in the transverse machine direction, e.g. reinforced edges of slop metallization. The standard masking system can only create free margins in the machine direction. Amber uses this kind of films from start for variety of capacitors with vast ranges for his valued customers.

The idea to use individual structured patterns films occurred in the early days when we started to manufacture motor run capacitors, for the same we performed long time R&D to have good quality product.

We use segment film with the following technical benefits:

  • Limit the current by inner fuses
  • Limit the energy per clearing
  • Well calculated algorithm to determine the energy/current for a fuse
  • Predictable behavior of the capacitor in case of damage
  • No fatal short or explosion and this means more safer units
  • Higher maximum breakdown voltage (due to series, parallel combination of segments)
  • Self-calibration breakdown behavior
  • Controlled working process, precise design and high quality materials
  • Capacitance loss after 100,000 cycles is 10 %, as well our all other series have 5 %

The fundamental idea of segmentation is to avoid a fatal breakdown in a capacitor and simultaneously take benefit from all other advantages of metalized dielectric films.

As a result of our R&D experience we want to deliver knowledge to our valued customers that they should take care about our product and their own equipment to have benefit of this technology.

  • Our product protection is just for internal fault, not for external faults
  • Don’t miss auxiliary protection of equipment on behalf of capacitor internal protection
  • Don’t short circuit directly to our protected capacitor(even for discharge) direct short circuit may lead to capacitance loss due to high inrush current flow through tiny fuses
  • Don’t let capacitor indirect heat
  • Our product is only for indoor applications