Elta STDL150-1EC-R Twinflow Centrifugal Box Fan Single Phase EC - 150mm (rectangular spigots)

The Elta STDL150-1EC-R is a Twinflow duty/standby centrifugal box fan for 150mm duct systems, with rectangular spigots sized 148 x 198mm. Two backward curved fans sit side by side in one acoustically lined case: one runs, the other waits on standby. At full speed it moves up to 493 m³/h free air, about 436 m³/h at 100 Pa, and still delivers 148 m³/h against 500 Pa.Each fan has an IP44 EC external rotor motor (220 to 240V single phase, 50/60Hz) with sealed for life bearings, and the case is 1.2mm galvanised mild steel. An auto changeover panel (149-ACO1/EDV) is fitted as standard, switching to the standby fan if the duty fan fails and sharing run hours between the two. Speed is set by the built in commissioning potentiometer or a 0-10V signal, and Elta give a 12 month (1 year) manufacturer warranty. 1 Phase EC Motor Up to 493 m³/h Speed Controllable What it is best used forWashroom, changing room and toilet core extract where a stopped fan is not acceptable: school and college toilet blocks, hotel bathroom risers, gym changing rooms, small office kitchenettes and internal meeting rooms. It gives 493 m³/h free air and about 436 m³/h at 100 Pa on 150mm ducting.It shares its motor with the 125mm model, so it is not the fan for high resistance systems: at 300 Pa it delivers about 302 m³/h. For bigger toilet cores or long runs, step up to the 200mm model.Why choose this over alternativesThe point of a twin fan is resilience. A single fan such as the Elta SSDL150-1EC-R Singleflow moves more air in the same duct size (662 m³/h free air against 493 m³/h here, and 324 m³/h at 500 Pa against 148 m³/h), but when its motor fails the extract stops until someone replaces it. The STDL150-1EC-R keeps running on its standby fan, the panel gives normally open fail and run contacts for a BMS or alarm, and the duty share means neither motor does all the hours. Choose it for windowless toilets, risers and any system where a dead fan means a complaint or a breach of the ventilation design