2.ALEA (LINE SURGE ARRESTER WITH AIR GAP)
The line  surge arrester with air gap (ALEA), is integrated with 5 or 10 kA nonlinear  resistive elements (zinc oxide varistors) encapsulated in polymeric concrete and  aluminum ironworks for its installation (included).

RELIABILITY OF THE ALEA
Mechanically,  the ALEA withstands  more than  200 kg since this equipment does not  support the insulator as in the case of the ADOM pin. Furthermore, the ALEA is  not connected to the system. For this reasons, in case of a mechanical failure  it will not cause permanent fault.

The material  used in its manufacturing process (Polymer Concrete ) is an insulating material  for outdoor use that does not fragment or projects particles in the case of a  surge arrester failure; besides, it eliminates moisture absorption due to its  encapsulating process.

The ALEA  fulfills the Specification CFE 52000-66 and IEC 99-4, showing an excellent  performance in the partial discharges tests.

The (ADOM)  has been evaluated in agreement with the  international standards with excellent results, among them:

The  characterization of the zinc oxide element was made with the voltage-leakage  current curve; The power arc  extinction of the arrangement occur in less than two milliseconds (1/8 cycle).  Tests of impulse current withstand and temporary over voltage (TOV) were carried  out according to ANSI/IEEE PC62.11 draft 3 (1992);The impulse tests include  impulses of low current long duration and impulses of high current short  duration. These tests allow to evaluate the mechanical, electrical and thermal  design of the surge arrester in agrrement with IEC 99-4. The operating cycle  tests showed excellent results, demonstrating an exceptional thermal stability. 

According to the same IEC Standard, the equipment resulted free of  partial discharges at rated voltage. The  ADOM pins fulfill the CFE 52000-05 specification.

1. ADOM (METAL OXIDE SURGE ARRESTER)
The metal  oxide surge arrester (ADOM) is integrated by elements that hold the cross arm  through a threaded galvanized iron bolt. The arrangement serves also as a  mechanical support to the pin type insulator.

3.ABT (LOW VOLTAGE SURGE ARRESTER)
The low voltage surge arrester (ABT), is  integrated with 10 kA non linear resistive elements (zinc oxide varistors)  encapsulated in a polymeric concrete body. The accessories used to attach the  ABT to the equipment to protect are made of brass ironworks and stainless steel  screws. As an  alternative for a technical-economical solution, MAPPEC developed the low  voltage surge arrester to protect electrical equipment and secondary coils of  transformers. In this last case, the surge arresters are connected directly to  the secondary bushing through the fixation ironwork and to Earth through  stainless steel screws.

RELIABILITY OF THE ABT
This type of  surge arrester is permanently connected to the low voltage system, protecting  the secondary side of the transformer (low voltage coil) impeding a failure due  to induced transients and over voltages in the low tension side of the  circuits. Its failure mechanism allows to avoid the use of  disconnecting switches since the arrester is divided in two parts without  projecting material fragments that could damage the transformer bushing or other  type of equipment installed in the transformer. The ABT allows to protect the  circuit for over voltages as low as 130 V.

4.AICP (INTEGRATED POLYMERIC CONCRETE SURGE ARRESTERS)
The  Integrated Polymeric Concrete Surge Arresters (AICP) are designed specifically  for the 23 kV systems of the utility LFC. They are installed as a mechanical  support of the pin type insulator 56-3 and are manufactured with an adjustable  arcing horn to set the protection level depending on the altitude over the sea  level.

RELIABILITY OF THE AICP
,This type of  Surge Arrester was developed considering that some 23 kV systems are  over-insulated for 34.5 kV systems, allowing its connection with the pin type  insulator 56-3. The arching  horn is adjustable to allow its setting to the desired protection level  depending on the altitude above the sea level.

Mechanically,  it supports over 400  kg, enough to support to the weight and mechanical  stresses caused by the conductor. It fulfills  the LFC-GDD-018 and IEC 99-4 specifications, showing an excellent performance in  the partial discharges and moisture absorption tests.