Have you ever considered how you would evacuate people from a multistorey building in case of power failure?
Do you have responsibility for people coming and going from public buildings? If you do, you need to consider how you’re going to handle evacuation in the event of an extended power failure and are not equipped with a standby generator.
It doesn’t need to be a dramatic situation just an extended power outage. Lifts by default should have the means to travel to the closest floor and open their doors so occupants can leave in the case of power failure. That is fine for able-bodied persons who are capable of continuing evacuation using the staircase.
How would you evacuate people with mobility issues?
A simple cost-effective solution is to power lift through UPS, however, it may not be as simple as it seems.
Suppliers and installers of UPS systems intended to support lifts should be aware that some lifts have regenerative braking, which generates a potentially damaging back–EMF onto the DC Bus within the UPS.
Your duty of care
If you have injured, incapacitated or disabled people in your building you need to have a plan in place to evacuate in any circumstance. This applies to any public building, including:
- Office buildings
- Schools and universities
- Libraries & Hospitals
Harnessing Energy with Regenerative Loads
The capacity of the lift motor, compactness, and high inrush are some of the features that can be easily managed for UPS’s on the market nowadays, but being able to handle regenerative loads is a completely different situation. Regenerative UPS units use the regenerative load from braking action; this load is used for creating regulated power which is connected to machines generating regenerative load.
Regenerative Uninterruptible Power Supply (UPS)
- When the Elevator is moving upwards with the load, the motor drive is in forwarding mode (normal mode) drawing energy from Utility or UPS
- The motor will converts the supplied electrical energy into kinetc energy
- Every elevator motors operate like a generator while braking when moving downwards with load
- During regenerative braking, the motor restores part of the kinetic energy into electrical energy
- This electrical energy will be directed to the Helios UPS, and use to charge the UPS battery or recycle back to the utility
- No energy is wasted
Other loads with braking applications
- Spindle drives
- Decanter centrifuges
- Synchronous motors