{"product_id":"dehn-900550-dg-tt-230-400-fm-surge-arrester","title":"DEHN 900550 DG TT 230 400 FM DEHNguard 3+1 Type 2 Surge Arrester (Pre-owned)","description":"\u003cp\u003eThe DEHN DEHNguard DG TT 230 400 FM, article number 900 550, is a type 2 surge arrester for 230\/400V TT and TN-S low voltage systems, made in Germany by DEHN. It is a 3+1 arrangement: three DEHNguard T 275 varistor modules (No. 900 670) protect L1, L2 and L3 to N, and one DEHNgap TC 255 spark gap module (No. 900 134) protects N to PE. The FM version adds a remote signalling changeover contact on terminals 11, 12 and 14.\u003c\/p\u003e\n\u003cp\u003eEach plug-in module has an operating state indicator window that shows green when the module is healthy and red when it needs replacing. The base mounts on 35mm DIN rail and occupies four modules. The T 275 modules are rated Uc 275V AC, In 20kA and Imax 40kA (8\/20) with a protection level Up of 1.25kV or lower. This is a used unit removed from a switchboard.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eBrand:\u003c\/strong\u003e DEHN\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eModel:\u003c\/strong\u003e DEHNguard DG TT 230 400 FM\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePart Number:\u003c\/strong\u003e 900 550\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eAlternate Part Number:\u003c\/strong\u003e 900550; modules 900 670 (T 275) and 900 134 (TC 255)\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Type 2 surge arrester, 3+1 circuit\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSystem:\u003c\/strong\u003e 230\/400V TT and TN-S\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSPD Type:\u003c\/strong\u003e Type 2 to EN 61643-11\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eUc (T 275 modules):\u003c\/strong\u003e 275V AC\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIn (8\/20):\u003c\/strong\u003e 20kA\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eImax (8\/20):\u003c\/strong\u003e 40kA\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eUp:\u003c\/strong\u003e 1.25kV or lower\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eRemote Signalling:\u003c\/strong\u003e Changeover contact, terminals 11\/12\/14\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMounting:\u003c\/strong\u003e 35mm DIN rail, 4 modules\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eSerial Number:\u003c\/strong\u003e 210764\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e Germany\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCondition:\u003c\/strong\u003e Used, removed from switchboard\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e3+1 circuit with varistor modules L-N and spark gap N-PE\u003c\/li\u003e\n\u003cli\u003ePlug-in modules with green\/red operating state indicators\u003c\/li\u003e\n\u003cli\u003eRemote signalling contact for monitoring\u003c\/li\u003e\n\u003cli\u003eDIN rail mounting\u003c\/li\u003e\n\u003cli\u003eSuccessor product is DEHNguard M TT 275 FM (952 315)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eTypical Applications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eSurge protection at the main distribution board of commercial and industrial buildings\u003c\/li\u003e\n\u003cli\u003eTT and TN-S supply systems\u003c\/li\u003e\n\u003cli\u003eReplacement for an existing DG TT 230 400 FM installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003ePackage Includes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 x DEHN DG TT 230 400 FM base with 3 x T 275 and 1 x TC 255 modules fitted, as photographed\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eAdditional Information\u003c\/h2\u003e\n\u003cp\u003eThe unit has not been electrically tested. The module indicator windows show the healthy colour in the listing photographs but the arrester should be checked by a licensed electrician before reuse.\u003c\/p\u003e\n\u003cp\u003eThis product has been discontinued by DEHN.\u003c\/p\u003e\n\u003cp\u003eThis was removed from an unused item and may show minor cosmetic marks from previous install. Please refer to the photographs for the overall condition.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShipping from Sydney, Australia.\u003c\/strong\u003e\u003c\/p\u003e","brand":"DEHN","offers":[{"title":"Default Title","offer_id":53103933456701,"sku":"S4326","price":149.26,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0953\/8931\/9485\/files\/20260918_134808.jpg?v=1789714545","url":"https:\/\/indrelec.com.au\/products\/dehn-900550-dg-tt-230-400-fm-surge-arrester","provider":"Indrelec","version":"1.0","type":"link"}