ACO Auto Changeover Panel Three Phase AC

The Elta 149-ACO3/B is an auto changeover panel for three phase AC twin fan units. It runs the duty fan and automatically changes over to the standby fan if the duty fan's thermal overload trips, or on loss of airflow where the twin fan unit has airflow switches.This is the automatic duty share model: an internal timer gives each fan a 12 hour duty cycle so both motors wear evenly. It runs on 400V three phase 50Hz plus neutral, uses industrial contactors with thermal overloads preset to the fans, and has a power lamp, fan fail lamp and rocker switch on the fascia in a 315 x 235 x 130 mm surface mounted enclosure. Run and standby Auto changeover panel Three phase AC What it is best used forTwin fan extract or supply where ventilation must keep running if one motor fails: toilet cores in offices and schools, car park and plant room extract, kitchens and residential common areas. It suits direct on line three phase twin fan units, with or without airflow switches.It is not suitable for use with inverters, and it is for three phase AC fans; EC twin fans need an EC changeover panel. A volt free fan fail output is on the 149-ACO3/BDV version, not this model.Why choose this over alternativesAgainst wiring two fans to manual switching, the panel changes over on its own the moment a thermal overload trips or airflow is lost, and the 12 hour auto duty share keeps run hours equal so the standby fan is not left seized. Elta's datasheets list the ACO panels against their twin fan ranges, and the ACOTO panels are compatible with Elta's EFSC and ATC speed controllers.If you need a volt free common fan fail signal for a BMS, ask us for the 149-ACO3/BDV, which adds it.Installation notes Check the panel supplied is compatible with the fan motors and that the thermal overloads are set to the motors' full load current. Install in a dry sheltered position, not close to a heat source. Remove the fascia screws for access to the fixing holes and terminals. Supply is 400V three phase 50Hz with neutral and earth. Wire to the ACO3TO diagram; if the twin fan unit has no airflow switches, omit connections 1 to 3 and do not link them out. To test changeover, move the timer jumper to the 1 minute test position, then return it to the 12 hour position. All wiring by a suitably qualified and competent person to current regulations. Browse more twin fans or Elta controllers, or call us for help choosing the right product.Specifications Model 149-ACO3/B (ACO3TO-ADS) Brand Elta Type Auto changeover panel, run and standby Supply 400V 3 phase 50Hz and neutral Fan type Three phase AC twin fan units (direct on line) Duty share Automatic, 12 hour cycle per fan Changeover trigger Thermal overload trip or loss of airflow (with airflow switches) Motor protection Contactors with preset thermal overloads Dimensions (H x W x D) 315 x 235 x 130 mm Mounting Surface Fascia Power lamp, fan fail lamp, rocker switch Remote enable Optional, from volt free contacts (230V ac rated) Fan fail output Volt free, on 149-ACO3/BDV version Inverter use Not suitable Manuals & Guides Elta Auto Changeover Panel Installation Instructions