WO2025229151A1

WO2025229151A1 - Smart ups

Info

Publication number: WO2025229151A1
Application number: PCT/EP2025/062018
Authority: WO
Inventors: Toni Kuikka
Original assignee: Eaton Intelligent Power Ltd
Current assignee: Eaton Intelligent Power Ltd
Priority date: 2024-05-03
Filing date: 2025-05-01
Publication date: 2025-11-06
Anticipated expiration: 2026-11-03
Also published as: GB202406228D0; GB2640734A

Abstract

Provided herein is an uninterruptible power supply, UPS, for connecting between one or more loads and a supply. The UPS comprises energy storage means configured to supply electrical power to the one or more loads when there is no electrical power from the supply. The UPS comprises a processor powered by the energy storage means and/or a controller configured to connect to an external safety circuit with a hardware off button. The processor is programmable to control operation of the UPS and/or the one or more loads, and is integrated into the UPS. The controller is configured, in response to detecting an event, to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads. A system comprising the UPS and one or more loads is also provided, along with a method of operating the UPS.

Description

Smart UPS

Field

This relates to a UPS, and to methods of operating the UPS.

Background

An uninterruptible power supply (UPS) or uninterruptible power source is a type of continual power system that automatically provides backup electric power to a load when the input power source or mains power fails. The load can be any hardware where unexpected power disruption would be undesirable (such as computers, data centres, telecommunication equipment or other electrical equipment). The load protected by a UPS can be termed 'protected equipment'.

A UPS can provide near-instantaneous protection from input power interruptions by switching to stored energy, e.g. energy stored in battery packs, supercapacitors or flywheels. The run-times of most UPSs on such stored energy can be relatively short, but are sufficient for initiating a standby power source (such as a generator) or properly shutting down the protected equipment or load.

The protected equipment and/or the UPS are typically controlled by an external automation system, for example an external programmable logic controller (or PLC) or a supervisory control and data acquisition (SCADA) system. This allows a user of the UPS to e.g. control the shutdown of the protected equipment or load by programming shutdown sequences for the UPS using the external automation system.

In use (i.e. when installed) a UPS is also required to have a physical (hardware) off button that is connected to the UPS with a cable. Activation of this off button breaks all the circuits connected to the UPS (and any other circuits in the environment, for safety reasons). However, breaking the circuits in this way stops the supply of power to the load or protected equipment and prevents the appropriate shutdown sequences from being performed. This can cause damage to the loads and/or other backend devices or processes, and/or the unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss.

It is therefore desirable to provide an alternative UPS which reduces or avoids some of these issues. Summary

Disclosed herein is an uninterruptible power supply, UPS, for connecting between one or more loads and a power supply. A system comprising the UPS and one or more loads is also provided, along with a method of operating the UPS.

The UPS comprises energy storage means configured to supply electrical power to the one or more loads when there is no electrical power from the supply. The UPS comprises a processor powered by the energy storage means and/or a controller configured to connect to an external safety circuit with a hardware off button. The processor is programmable to control operation of the UPS and/or the one or more loads, and is integrated into the UPS. The controller is configured, in response to detecting an event, to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads.

In accordance with a first aspect there is provided an uninterruptible power supply, UPS, for connecting between one or more loads and a supply. The UPS comprises energy storage means configured to supply electrical power to the one or more loads when there is no electrical power from the supply. The UPS further comprises a processor powered by the energy storage means, wherein the processor is programmable to control operation of the UPS and/or the one or more loads and is integrated into the UPS.

In previous UPS arrangements, the one or more loads (e.g. the protected equipment) and/or the UPS are controlled by an external automation system, for example an external programmable logic controller (PLC) or a supervisory control and data acquisition (SCADA) system. This allows a user of the UPS to e.g. control the shutdown of the protected equipment or load by programming shutdown sequences for the UPS using the external automation system. However, external automation systems require external power and cabling between the various inputs/outputs of the UPS. This can increase the cost and complexity of the UPS, and increase the difficulty of installation.

By integrating a processor into the UPS itself, which draws power directly from the energy storage means of the UPS, there is no need for external power and cabling can be reduced. Moreover, there is no need for a separate external automation system. A cheaper, easier to install UPS may therefore be provided, without compromising on the underlying functionality. In particular, the integrated processor is user programmable in the same or similar way as a PLC or other external automation system to control operation of the UPS and/or the one or more loads. The processor is internal user programmable.

In some implementations, the processor is programmable to control operation of the UPS and/or the one or more loads based on the supply of electrical power from the energy storage means. For example, a user can designate critical loads from the one or more loads, which critical loads are prioritised over the other loads. Optionally, the processor is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on the supply of electrical power from the energy storage means. In some implementations, the processor is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on one or more programmed timings and/or one or more programmed sequences.

By controlling the UPS and/or the one or more loads in a smart manner based on the supply of power from the UPS, programmed timings and/or programmed sequences, energy usage can be effectively prioritised. The UPS can therefore run for longer, reducing the risk of shutdown of critical systems. Additionally or alternatively, a cheaper and/or smaller energy storage means of the UPS and/or back up electrical power supply can be used. A smaller, cheaper and more efficient UPS may therefore be provided.

In some implementations, the one or more loads comprises at least one load that is designated as a critical load and at least one load that is designated as a non-critical load, and the processor is programmable to control the UPS and/or the one or more loads to shut down the at least one non-critical load or move the at least one non- critical load to a low-power state while the at least one critical load is being supplied with power. Optionally, the one or more loads comprises a plurality of loads designated as non-critical loads, and wherein the processor is programmable to control the UPS and/or the one or more loads to cause the plurality of non-critical loads to be sequentially shut down or sequentially moved to low-power states based on the stored energy of the energy storage means decreasing.

In some implementations, the processor is programmable using a programmable logic controller, PLC, programming language. Optionally, the processor is programmable using: Ladder Logic; Function Block Diagram; Sequential Function Charts; Structured Text; or Instruction List. The use of PLC programming languages facilitates use of the UPS described herein as a direct replacement for an existing PLC, since a customer can program the internal user programmable processor in the same or similar way.

In some implementations, the UPS of the first aspect further comprises a controller configured to connect to an external safety circuit with a hardware off button. In response to detecting an event, the controller is configured to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads. In this regard, the controller can be considered to be a safety critical controller.

UPS devices are required to have a physical (hardware) off button that is connected to the UPS with a cable. Activation of this off button breaks all the circuits connected to the UPS (and any other circuits in the environment, for safety reasons). However, breaking the circuits in this way stops the supply of power to the load or protected equipment and prevents the appropriate shutdown sequences from being performed. This can cause damage to the loads and/or other backend devices or processes, and/or the unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss. By providing an additional controller which is configured to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads in response to detecting an event, a smarter UPS may be provided which improves the functionality of the safety circuit beyond the required hardware.

A method of operating the UPS of the first aspect comprises: programming an internal user programmable processor to control operation of the UPS and/or the one or more loads; supplying electrical power to the one or more loads from the energy storage means when there is no electrical power from the supply; and controlling operation of the UPS and/or the one or more loads in accordance with the programmed processer.

In accordance with a second aspect there is provided an uninterruptible power supply, UPS, for connecting between one or more loads and a supply. The UPS comprises energy storage means configured to supply electrical power to the one or more loads when there is no electrical power from the supply. The UPS further comprises a controller configured to connect to an external safety circuit with a hardware off button, wherein the controller is configured, in response to detecting an event, to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads.

As discussed above, UPS devices are required to have a physical (hardware) off button that is connected to the UPS with a cable. However, activation of this off button breaks all the circuits connected to the UPS, which cause damage to the loads and/or other backend devices or process, and/or the unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss. By providing a controller which is configured to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads in response to detecting an event, a smarter UPS may be provided which improves the functionality of the safety circuit beyond the required hardware. In particular, appropriate responses can be taken to different events being detected, allowing for a more intelligent control of the UPS and/or the one or more loads whilst still ensuring the safety of the equipment and any users/operators within the environment. Such software based implementations can be provided in addition to the existing physical hardware off button, improving functionality of the UPS.

The controller can be powered by the UPS, for example by the energy storage means of the UPS. This provides an integrated safety critical controller which does not rely on external power supplies. Optionally, the controller is configured to send a signal to the one or more loads indicating that a shutdown sequence will be initiated. In this way, the loads (or protected equipment) can get a 'heads up' that a shutdown will occur, enabling the loads to perform any necessary steps before the shutdown occurs. An improved shut down can therefore be provided which minimises the risk of data loss or back end damage.

In some implementations, the UPS further comprises one or more sensors, wherein the event comprises a sensor measurement satisfying a predetermined criteria. The sensors can be integrated with the UPS or otherwise located within the environment of the UPS and associated with the UPS.

Optionally, the one or more sensors comprise a temperature sensor, and the event comprises a measured temperature exceeding a predetermined threshold. Optionally, the one or more sensors comprise a sensor configured to detect a status of an enclosure of the UPS or a status of an enclosure of the one or more loads, and the event comprises an incorrect status. For example, the status of the enclosure may indicate that a door of the enclosure is open when it shouldn't be, that equipment is not properly secured or connected within the enclosure, or that critical equipment is missing, for example. By using sensors as an input signal to control of the UPS and/or the one or more loads in this way, the safety critical circuit can be improved and can be implemented more intelligently, and to take account of more events, than a standard hardware off button. In some implementations, the UPS of the second aspect further comprises a processor powered by the energy storage means, wherein the processor is integrated into the UPS and is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads. Optionally, the processor is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on a signal from the controller. In other words, the processor may control the shutdown (instead of the safety critical controller). In other examples, the controller may control the shutdown.

A method of operating the UPS of the second aspect comprises: supplying electrical power to the one or more loads from the energy storage means when there is no electrical power from the supply; detecting occurrence of an event; and, in response to detecting the event, initiating a safe mode of the UPS or initiating a shutdown sequence of the one or more loads.

Also disclosed herein is a system comprising one or more loads and the UPS of the first or second aspect.

It will be understood that features described with reference to the UPS of the first aspect may be combined with the UPS of the second aspect, and vice versa.

List of Figures

The detailed description is with reference to the following figures:

Figure 1A is a schematic illustration of UPS in accordance with the prior art;

Figure IB is a schematic illustration of a UPS in accordance with the first aspect described herein;

Figure 2A is a schematic illustration of UPS in accordance with the prior art;

Figure 2B is a schematic illustration of a UPS in accordance with the second aspect described herein; and

Figure 3 is a schematic illustration of a system comprising the UPS of the first and/or second aspects.

Detailed description

Disclosed herein is an uninterruptible power supply, UPS, for connecting between one or more loads and a power supply. In conventional arrangements, as illustrated in Figure 1A, a UPS 10 is connected between one or more loads 12 (also referred to herein as protected equipment) and a power supply 20. The load I equipment 12 can be any hardware where unexpected power disruption would be undesirable (such as computers, data centres, telecommunication equipment or other electrical equipment). The power supply can be any form of grid or mains supply of electrical power.

The UPS 10 comprises an energy storage means 14. The storage means can be any suitable means for storing energy, including but not limited to battery packs, supercapacitors or flywheels. In the following examples, means 14 will be described as one or more batteries, but it is understood that any suitable energy storage means can be used. An external automation system 16, such as a PLC or SCADA system is in communication with the UPS 10 over any suitable wired and/or wireless communication means. The system 16 is also in communication with the loads 12.

A backup or standby energy supply 18 is also provided. This can be a generator, large battery, or any other suitable means of supplying electrical power in the power supply 20 fails. The UPS 10 provides short term supplies of energy while the standby energy supply (or standby power source) 18 starts up, ensuring there is no disruption of the electrical power supplied to the loads 12.

However, the use of external automation systems 16 require external power and cabling between the various inputs/outputs of the UPS. This can increase the cost and complexity of the UPS, and increase the difficulty of installation of the UPS 10 in an environment.

With reference to Figure IB, one or more of these drawbacks can be reduced or mitigated by the use of a processer 106 which is integrated into the UPS. This processor 106 can be used in place of the external automation system 16 of Figure 1A.

As shown in Figure IB, in accordance with a first aspect there is provided an uninterruptible power supply, UPS, 100 for connecting between one or more loads 12 and a supply 20. The UPS comprises energy storage means 14 configured to supply electrical power to the one or more loads 12 when there is no electrical power from the supply. The storage means 14, loads 12, supply 20 and standby energy supply 18 are all as described with reference to Figure 1A. The UPS 100 of Figure 1A further comprises the processor 106, which is powered by the energy storage means 14. The processor is programmable to control operation of the UPS and/or the one or more loads and is integrated into the UPS. The processor 106 is internal user programmable. Any suitable internal user programmable processor can be used, including but not limited to: Central Processing Units (CPUs), Multi-Core Processors, Microprocessors and Field-Programmable Gate Arrays (FPGAs); Digital Signal Processors (DSPs); and an Application-Specific Integrated Circuit (ASIC).

In some implementations, the processor is programmable using a programmable logic controller, PLC, programming language. Any suitable language can be used, including but not limited to: Ladder Logic; Function Block Diagram; Sequential Function Charts; Structured Text; or Instruction List. The use of PLC programming languages facilitates use of the UPS 100 with integrated process 106 as a direct replacement for an existing PLC or external automation system 16, since a customer can program the internal user programmable processor in the same or similar way to conventional equipment.

By integrating a processor into the UPS itself, which draws power directly from the energy storage means of the UPS, there is no need for external power and cabling can be reduced. Moreover, there is no need for a separate external automation system 16. A cheaper, easier to install UPS may therefore be provided, without compromising on the underlying functionality. In particular, the integrated processor 106 is user programmable in the same or similar way as a PLC or other external automation system 16 to control operation of the UPS and/or the one or more loads.

In some implementations, the processor 106 is programmable to control operation of the UPS 100 and/or the one or more loads 12 based on the supply of electrical power from the energy storage means 14. For example, a user can program the processor 106 to designate critical loads from the one or more loads 12; these critical loads can then be prioritised by the processor 106 I UPS 100. For example, non-critical loads may be shut down, or moved to a low power or standby state, whilst critical loads are provided with electrical power. The allocation of power to the load 12 can be dependent on the supply of energy from the batteries 14. For example, as battery capacity decreases, more loads 12 may be shut down or moved to standby, so that the most critical loads can be prioritised.

By controlling the UPS and/or the one or more loads in a smart manner based on the supply of power from the UPS, energy usage can be effectively prioritised. The UPS can therefore run for longer, reducing the risk of shutdown of critical systems. Additionally or alternatively, a cheaper and/or smaller energy storage means of the UPS and/or back up electrical power supply can be used. A smaller, cheaper and more efficient UPS may therefore be provided.

In some implementations, the processor 106 is programmable to control the UPS 100 and/or the one or more loads 12 to shut down at least one of the one or more loads 12 based on one or more programmed timings and/or one or more programmed sequences. This may allow loads 12 to be shut down in the correct order, reducing the risk of data loss or damage to the equipment during the shutdown. By controlling the UPS and/or the one or more loads in a smart manner based on programmed timings and/or programmed sequences, the loads 12 may be appropriately shutdown, reducing the risk of an unexpected or incorrect shutdown of critical systems.

The UPS 10 of Figure 1A is now described further with reference to Figure 2A.

Although not shown, the features of Figure 1A can be incorporated into Figure 2A. In other words, the loads 12, supply 20 and standby power supply 18 (not shown) can all be combined with the UPS 10 shown in Figure 2A (or vice versa).

In conventional arrangements, as illustrated in Figure 2A, the UPS 10 is connected to an external safety circuit 24 having a hardware off button 22. In particular, UPS devices are required to have a physical (hardware) off button 22 that is connected to the UPS with a physical cable (here circuit 24). Activation of this off button 22 breaks all the circuits connected to the UPS (and any other circuits in the environment, for safety reasons). This arrangement is safety critical.

However, breaking the circuits in this way stops the supply of power to the load 12 or protected equipment and prevents the appropriate shutdown sequences from being performed. This can cause damage to the loads 12 and/or other backend devices or processes, and/or the unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss.

With reference to Figure 2B, one or more of these drawbacks can be reduced or mitigated by the use of a controller 260 which is integrated into the UPS 100'. This controller 260 can be used in combination with the hardware button 22 of Figure 2A. In other words, the UPS 100' comprises a controller 260 configured to connect to the external safety circuit 24 with a hardware off button 22. The controller 260 is configured, in response to detecting an event, to initiate a safe mode of the UPS 100' or initiate a shutdown sequence of the one or more loads 12. In this way, the controller 260 can be considered as a safety critical controller. The controller can be implemented in any suitable manner, with any suitable type of processor and memory. Optionally the controller is implemented as a microcontroller.

By providing an additional controller which is configured to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads in response to detecting an event, a smarter UPS may be provided which improves the functionality of the safety circuit beyond the required hardware. In particular, appropriate responses can be taken to different events being detected, allowing for a more intelligent control of the UPS and/or the one or more loads whilst still ensuring the safety of the equipment and any users/operators within the environment. Such software based implementations can be provided in addition to the existing physical hardware off button 22, thereby improving functionality of the UPS by allowing more intelligent and nuanced control. In addition, by detecting events as they occur, pre-emptive shut down measures can be taken for a particular UPS 100', avoiding the need to kill the power to all devices and systems within a single environment through the hardware button 22.

The controller 260 can be powered by the UPS 100', for example by the energy storage means 14 of the UPS. This provides an integrated safety critical controller which does not rely on external power supplies.

The controller 260 can be configured to send a signal to the one or more loads 12 indicating that a shutdown sequence will be initiated. In this way, the loads (or protected equipment) can get a 'heads up' that a shutdown will occur, enabling the loads 12 to perform any necessary steps to preserve data or system statuses before the shutdown occurs. An improved shut down can therefore be provided, which minimises the risk of data loss or back end damage. The controller 260 can control the shutdown of the load 12 itself, or can provide a signal to a processor, such as processor 106 or external automation system 16, to cause the processor to control the shutdown (instead of the safety critical controller).

The event that is detected can be any suitable event capable of detection by the controller 260. Event data can be received by the controller 260 periodically (for example, every minute, every hour), or the event data can be received in real time or substantially real time. This can allow for real time monitoring of the UPS 100', ensuring a dangerous situation can be detected as soon as it arises and the loads 12 can be appropriately shutdown. One or more processing steps or logic can be applied to the received event data to detect the event, for example by applying one or more criteria or thresholds to the event data.

For example, although not shown in Figure 2B, the controller 260 can receive signals from the rest of the UPS, the processor 106 (if present), the loads 12, the standby power supply 18, etc. and detect an event based on one or more of those signals satisfying a predetermined criteria. The signals can be voltage or current signals, and the predetermined criteria can comprise the voltage or current signal being greater than (optionally equal to) or being less than (optionally equal to) a predetermined threshold, for example.

Additionally or alternatively, the UPS 100' of Figure 2B further comprises one or more sensors 280, wherein the event comprises a sensor measurement satisfying a predetermined criteria or exceeding a predetermined threshold. The sensors 280 can be integrated with the UPS or otherwise located within the environment of the UPS and associated with the UPS. The sensor measurements from the sensors 280 can be received at the controller 260. The sensor measurements can comprise a voltage or current signal, depending on the arrangement of the sensors 280.

In some examples, the one or more sensors comprise a temperature sensor, and the event comprises a measured temperature exceeding a predetermined threshold, in some examples, the one or more sensors comprise a sensor configured to detect a status of an enclosure of the UPS or a status of an enclosure of the one or more loads, and the event comprises an incorrect status. For example, the status of the enclosure may indicate that a door of the enclosure housing the UPS 100' or the loads 12 is open when it shouldn't be, that equipment is not properly secured or connected within the enclosure, or that critical equipment is missing, for example.

By using signals and/or sensor measurements as input to control shutdown of the UPS and/or the one or more loads in this way, the safety critical circuit can be improved and can be implemented more intelligently. In particular, it is possible to take account of multiple different events and control the UPS 100' and/or the loads 12 based on said events. Moreover, because the event detection can be implemented at least in part in software, it is possible to update and adapt the event detection over time. A smarter UPS can be provided as compared to the conventional UPS 10 with a standard hardware off button shown in Figure 2A. The controller 260 of Figure 2B can be implemented in combination with the conventional arrangement shown in Figure 1A or the first aspect shown in Figure IB. Similarly, the processor 106 of Figure IB can be implemented in combination with the conventional arrangement shown in Figure 2A or the second aspect shown in Figure 2B. In other words, the controller and processor can be provided separately, or in combination with one another.

With reference to Figure 3, a system 300 is shown. The system comprises one or more loads 12, as described above, and the UPS 100, 100' of the first and/or second aspects. The system may also comprise the standby power supply 18 of Figures 1A,

IB, and any other features described above with respect to the first and second aspects.

It will be understood that, even where not explicitly described, the features provided herein can be combined in any suitable combination.

Claims

1. An uninterruptible power supply (100), UPS, for connecting between one or more loads (12) and a supply (20), the UPS comprising: energy storage means (14) configured to supply electrical power to the one or more loads (12) when there is no electrical power from the supply; and a processor (106) powered by the energy storage means, wherein the processor is integrated into the UPS and is programmable to control operation of the UPS and/or the one or more loads.

2. The UPS of claim 1, wherein the processor is programmable to control operation of the UPS and/or the one or more loads based on the supply of electrical power from the energy storage means.

3. The UPS of claim 2, wherein the processor being programmable to control operation of the UPS and/or the one or more loads comprises the processor being programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on the supply of electrical power from the energy storage means.

4. The UPS of claim 2 or claim 3, wherein the one or more loads comprises at least one load that is designated as a critical load and at least one load that is designated as a non-critical load, and wherein the processor is programmable to control the UPS and/or the one or more loads to shut down the at least one non-critical load or move the at least one non-critical load to a low-power state while the at least one critical load is being supplied with power.

5. The UPS of claim 4, wherein the one or more loads comprises a plurality of loads designated as non-critical loads, and wherein the processor is programmable to control the UPS and/or the one or more loads to cause the plurality of non-critical loads to be sequentially shut down or sequentially moved to low-power states based on the stored energy of the energy storage means decreasing.

6. The UPS of any preceding claim, wherein the processor is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on one or more programmed timings and/or one or more programmed sequences.

7. The UPS of any preceding claim, wherein the UPS further comprises a controller configured to connect to an external safety circuit with a hardware off button, and wherein, in response to detecting an event, the controller is configured to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads.

8. An uninterruptible power supply (100'), UPS, for connecting between one or more loads (12) and a supply (20), the UPS comprising: energy storage means (14) configured to supply electrical power to the one or more loads when there is no electrical power from the supply; and a controller (260) configured to connect to an external safety circuit (24) with a hardware off button (22), wherein the controller is configured, in response to detecting an event, to initiate a safe mode of the UPS or initiate a shutdown sequence of the one or more loads.

9. The UPS of claim 8, further comprising one or more sensors (280), wherein the event comprises a sensor measurement satisfying a predetermined criteria.

10. The UPS of claim 9, wherein the one or more sensors comprise a temperature sensor, and wherein the event comprises a measured temperature exceeding a predetermined threshold.

11. The UPS of claim 8 or claim 9, wherein the one or more sensors comprise a sensor configured to detect a status of an enclosure of the UPS or a status of an enclosure of the one or more loads, and wherein the event comprises an incorrect status.

12. The UPS of any of claims 8 to 11, further comprising a processor powered by the energy storage means, wherein the processor is integrated into the UPS and is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads.

13. The UPS of claim 12, wherein the processor is programmable to control the UPS and/or the one or more loads to shut down at least one of the one or more loads based on a signal from the controller.

14. The UPS of any of claims 8 to 13, wherein the controller is configured to send a signal to the one or more loads indicating that a shutdown sequence will be initiated.

15. A system comprising: one or more loads; the UPS of any preceding claim.