Emergency operations requiring the intervention of a lift operator
These procedures are represented in the files attached below
Automatic return to floor systems
Electric systems
Type A – Automatic return to nearest floor – Automatic Emergency VVVF EN81-20/81-1 with external UPS
The automatic return system (automatic emergency) to the nearest floor requires that the control panel, following a blackout or brief absence of power, automatically returns the cabin to the nearest floor, without intervention by third parties.
The Pitagora 4.0 control panel, if equipped with this option, is set up with an external UPS sized according to the size of the inverter. The control panel, once it has entered emergency mode and before starting to move the cabin towards the floor, performs a check to understand the favorable direction (i.e. it identifies the direction in which the inverter supplies less current to the motor and therefore where there is less absorption towards the UPS).
This is because the UPS is sized to make a short run and therefore has limited autonomy. Once it reaches the floor, the control panel will open the doors to let the trapped people out and close them again. Once the maneuver is finished, the control panel and the UPS will switch off after a pre-set time of 5 minutes.
The panel and UPS will resume normal operation once power is restored.
Type B – Automatic return to nearest floor – Integrated Emergency GEARLESS EN81-20
The Pitagora 4.0 EN81-20 control panel, if combined with a Gearless motor, provides an integrated maneuver in the event of a blackout using the device that allows manual maneuvering due to unbalance already present in the control panel. The automatic return system (automatic emergency) to the nearest floor provides that the control panel, following a blackout or a brief absence of power, autonomously brings the cabin back to the nearest floor in the favorable direction (depending on the load present in the cabin), with only the opening of the brakes and the speed control. The braking torque of motors of this type should guarantee a limited speed of movement, otherwise the panel keeps it under control with a modulation of the brakes until the nearest floor is reached. Once the floor is reached, the panel will open the doors to let the trapped people out and close them again. The panel will resume normal operation once the power is restored.
Type C – Automatic return to the preset floor – Automatic Emergency VVVF EN81-20/81-1 with external UPS
The automatic emergency maneuver to a pre-established floor requires that the control panel, following a blackout or a brief absence of power, returns the cabin to a pre-established floor. The control panel is equipped with an external UPS that is sized according to the system, given that it is necessary to take into account variants that can vary from system to system (motor power, shaft length, emergency speed, cabin weight, cabin capacity, etc.). The control panel, once it has entered emergency mode, will direct the cabin to the pre-established floor. Once it has reached the pre-established floor, the control panel will open the doors to allow the trapped people to exit and close them again. Once the maneuver is finished, the control panel and the UPS will switch off after a pre-established time of 5 minutes. The control panel and the UPS will resume normal operation once the power has been restored.
Hydraulic systems
The automatic emergency maneuver at the floor, in the case of hydraulic elevators, requires that the control panel, following a blackout or a brief absence of power, brings the cabin down to the lowest floor. The control panel is equipped with a small UPS to restart the peripherals of the control panel. The control panel must always also be equipped with the emergency buffer circuit.
The control panel, once it has entered emergency mode, begins to move the cabin towards the floor using the descent valve until it reaches the floor. Once the cabin reaches the floor, the control panel will open the doors to allow the trapped people to disembark and close them again. Once the maneuver is complete, the control panel and the UPS turn off. The control panel will resume normal operation once the power has been restored.
