港鐵指,昨日下午5時許藍田站路軌旁懷疑因為短路,引致道岔設備一件絕緣膠起火。港鐵及消防人員隨即到場處理,列車服務在晚上約6時半恢復正常。 orangenews 潘焯鴻 fb SER signal equipment room: facebook 波口: hkrail fandom typical case: high resistance in electrical connections > high temperature rise in conducting wire > protective insulation overheat > melt > smoke. the insulation material should be flame retardant. but what cause such high resistance? loose mechanical contact? 線耳 nuts and bolts not fully tightened? 線耳 soldering / crimping defect? there should be no high voltages, so electric arc-ing related issues can be eliminated. the faulty components analysis is most critical. OTOH, whether 2 incidents are co - related, is not so important, as they are 10+ hours apart, and do multiply to a bigger and more damaging incident.