{"id":2765,"date":"2023-03-23T11:55:58","date_gmt":"2023-03-23T03:55:58","guid":{"rendered":"https:\/\/www.wolunelectric.com\/?post_type=product&p=2765"},"modified":"2026-05-20T10:41:48","modified_gmt":"2026-05-20T02:41:48","slug":"fn18-high-voltage-indoor-load-break-switchequivalent-to-abb-nal-load-break-switch","status":"publish","type":"product","link":"https:\/\/www.wolunelectric.com\/th\/product\/fn18-high-voltage-indoor-load-break-switchequivalent-to-abb-nal-load-break-switch\/","title":{"rendered":"FN18 High Voltage Indoor Load Break Switch(Equivalent to ABB NAL load break switch )"},"content":{"rendered":"

Introduction<\/h2>\n

FN18 is a general purpose, three-pole, load break switch that offers switchgear owners and assemblers the advantages of an advanced interrupting technology and proven, dependable performance in a compact design.<\/p>\n

The switch is available to switchgear assemblers as a building block for metal-enclosed and pad-mounted switchgear applications in ratings from 12 upto 24kV.<\/p>\n

The standard FN18 switch includes a heavy-duty steel frame with stand-off insulators, a unique puffer-type arc extinguishing system, an operating mechanism and current-carrying components, including blade-type interrupters with cast hinges and jaw connectors.<\/p>\n

Optional accessories and features include a variety of operating handles, a motor operator, auxiliary switches, a shunt trip device, fuse bases, mechanical fuse tripping, grounding switches, mechanical door interlocking and key interlocking.<\/p>\n

 <\/p>\n

Main Product Features<\/h2>\n

FN18 switch disconnectors are based on a modular principle, which gives it a wide range of functionality. With a unique design that extinguishes electric arcs and enables
\nhigh switching capacity, they represent an attractive solution as a key breaking element for applications in enclosed switchgear and transformer compact substations.<\/p>\n

In combination with current limiting fuses, FN18-F fuse switch disconnectors ensure control over the full range of overload and short-circuit currents.<\/p>\n

The basic unit consists of a frame with insulators and current carrying parts.<\/p>\n

Two different types of operating mechanisms, snap action mechanism type K or stored spring energy mechanism type A, can be mounted on the frame.<\/p>\n

Fuse bases with or without fuse tripping mechanism, and an earthing switch type , suitable for both direct mounting and free standing components, complete the basic equipment of a switch disconnector. These modules can be easily configured according
\nto customer expectations.<\/p>\n

Accessories, such as shunt trip, under-voltage release, auxiliary switches, motor operation and various systems for manual operation can easily be added.<\/p>\n

 <\/p>\n

\"fn18
\u00a0 \u00a0 \u00a0FN18(NAL) load break switch hung on the wall<\/strong><\/figcaption><\/figure>\n

 <\/p>\n

\"fn18
FN18(NAL) load break switch installed in the switchgear<\/strong><\/figcaption><\/figure>\n
<\/div>\n

Technical Specification<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Technical Specification<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
Rated voltage<\/td>\nkV<\/td>\n12<\/td>\n24<\/td>\n<\/tr>\n
Rated current<\/td>\nA<\/td>\n630<\/td>\n630<\/td>\n<\/tr>\n
Rated power frequency<\/td>\nHz<\/td>\n50\/60<\/td>\n50\/60<\/td>\n<\/tr>\n
Short circuit making capacity<\/td>\nkA Peak.<\/td>\n50<\/td>\n50<\/td>\n<\/tr>\n
Peak withstand current<\/td>\nkA Peak.<\/td>\n50<\/td>\n50<\/td>\n<\/tr>\n
Short time current<\/td>\nkA eff.<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
1Sec.<\/td>\n<\/td>\n31.5<\/td>\n25<\/td>\n<\/tr>\n
2Sec.<\/td>\n<\/td>\n25<\/td>\n25<\/td>\n<\/tr>\n
3Sec.<\/td>\n<\/td>\n20<\/td>\n16<\/td>\n<\/tr>\n
Max. breaking capacity in co-operation with fuses IEC 62271-105 (IEC 420 1990-11)<\/td>\nA<\/td>\n1600<\/td>\n900<\/td>\n<\/tr>\n
Max. fuse current(XRNT Fuse)<\/td>\nA<\/td>\n200<\/td>\n200<\/td>\n<\/tr>\n
Power frequency withstand voltage 50Hz 1 min,:<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
– To earth and between poles<\/td>\nkV<\/td>\n42<\/td>\n65<\/td>\n<\/tr>\n
– Across isolating distance<\/td>\nkV<\/td>\n48<\/td>\n79<\/td>\n<\/tr>\n
Impulse withstand voltage 1.2\/50\u03bc<\/strong><\/b>\u00a0s:<\/td>\n<\/td>\n<\/td>\n<\/td>\n<\/tr>\n
– To earth and between poles<\/td>\nkV<\/td>\n75<\/td>\n125<\/td>\n<\/tr>\n
– Across isolating distance<\/td>\nkV<\/td>\n85<\/td>\n145<\/td>\n<\/tr>\n
Mechanism Endurance<\/td>\ncycles<\/td>\n2000<\/td>\n2000<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

 <\/p>\n

Basic Desigins<\/h2>\n

\"fn18<\/p>\n

    \n
  • \n

    FN18 load break switch<\/h3>\n<\/li>\n<\/ul>\n

    standard feature consists of chassis, insulators and current
    \ncarrying parts with the following pole distance:
    \n\u2013 12 kV \u2013 pole distance 150 mm, 170 mm and 210 mm
    \n\u2013 17.5 kV \u2013 pole distance 170 mm and 210 mm
    \n\u2013 24 kV \u2013 pole distance 170 mm*, 235 mm and 275 mm
    \n\u2013 36\/40.5 kV \u2013 pole distance 360 mm
    \n* \u2013 with insulating barriers
    \nRated currents are:
    \n\u2013 400, 630 and 1250 A up to 24 kV
    \n\u2013 630\/800\/1000 A for 36\/40.5 kV<\/h4>\n
      \n
    • \n

      FN18 load break switch with fuse<\/h3>\n<\/li>\n<\/ul>\n

      Is delivered with the same pole distances as the standard feature.
      \nFuse base type F is delivered for installation on both the opening and pivot sides, with or without automatic tripping.
      \nA fuse base with six insulators can also be delivered separately with some form of signal indication when a fuse blows or for installation on the pivot side of the switch<\/p>\n

        \n
      • \n

        Mechanisms<\/h3>\n<\/li>\n<\/ul>\n

        Type A with two springs
        \nThe opening spring is always charged before the switch can be closed by means of a closing spring. This means the opening spring is always charged in a closed switch, which in turn can be
        \ntripped immediately by hand, electrically or by a fuse-link striker system.<\/p>\n

        Type K with one spring
        \nClosing or opening the switch is performed by charging the springpast the dead centre.<\/p>\n

        A and K mechanisms may cooperate with motor drives.<\/p>\n

          \n
        • \n

          Earthing Switch<\/h3>\n<\/li>\n<\/ul>\n

          D type earthing switch<\/p>\n

          This type of earthing switch is equipped with a quick spring mech\u0002anism. It can be mounted on the pivot side of the switch
          \ndisconnector or on the fuse base when the latter is on the pivot
          \nside of the switch.<\/p>\n

          DB type earthing switch<\/p>\n

          Designed to be an independent assembly for both sides of the
          \ndisconnector.<\/p>\n

          <\/h2>\n

          Overall and installation dimensions<\/strong><\/h2>\n

          \"fn18<\/p>\n

          \"fn18
          fn18(NAL) load break switch with earthing switch<\/strong><\/figcaption><\/figure>\n
          \"fn18
          FN18(NAL) load break switch<\/strong><\/figcaption><\/figure>\n
          \"fn18
          FN18 12kV load break switch with current limiting fuse<\/strong><\/figcaption><\/figure>\n

           <\/p>","protected":false},"excerpt":{"rendered":"

          FN18 high voltage indoor load break switch is an air insulated medium voltage switch disconnector designed as an equivalent to ABB NAL load break switch.<\/p>\n

          Featuring compact modular construction, puffer arc extinguishing technology, and reliable switching performance, it is ideal for RMU, switchgear, and transformer protection applications.<\/p>","protected":false},"featured_media":2775,"template":"","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"FN18 High Voltage Indoor Load Break Switch | Equivalent to ABB NAL Load Break Switch","_seopress_titles_desc":"FN18 indoor high voltage load break switch equivalent to ABB NAL\/NALF. Available from 12kV to 40.5kV with 400A\u20131250A ratings, fuse combination, and earthing switch options.","_seopress_robots_index":""},"product_brand":[],"product_cat":[46],"product_tag":[],"class_list":{"0":"post-2765","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-high-voltage-disconnect-switch","8":"first","9":"instock","10":"shipping-taxable","11":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/product\/2765","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/media\/2775"}],"wp:attachment":[{"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/media?parent=2765"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/product_brand?post=2765"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/product_cat?post=2765"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.wolunelectric.com\/th\/wp-json\/wp\/v2\/product_tag?post=2765"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}