An isolated power supply (IPS) and an uninterruptible power supply (UPS) are both important components of a hospital’s electrical infrastructure, and although they serve different purposes, together they ensure patient safety and continuity of care, protect expensive and sensitive medical equipment, maintain the IT infrastructure, and comply with regulations and standards.
An isolated power supply is used to provide electrical power to critical medical equipment in a hospital. This equipment often requires a specific type of electrical power, such as a clean, constant voltage and frequency, to function properly. An isolated power supply is typically used in conjunction with a transformer to isolate the incoming power in a medical location for safety and performance purposes. Used to increase resilience wherever there is a need for higher availability from the power supply, an IPS ATS (automatic transfer switch) monitors the two AC systems for voltages and frequencies that exceed the limits. When either the voltage or frequency exceed the limits, the device will switch to the reserve AC line, ensuring that the critical equipment can continue to operate without interruption.
A back-up power source
The UPS, on the other hand, is a back-up power source that provides temporary power to the hospital’s electrical systems in the event of a power outage. This is critical in a hospital setting, as an interruption of power can have severe consequences for patients, such as interrupting life-sustaining equipment within medical locations. The UPS is required as a tertiary back-up system, is typically powered by batteries, and can provide power to required locations for up to 60 minutes. In reality, a UPS backs up the hospital’s electrical systems for a short period of time (often several minutes) until the back-up generators or secondary power systems kick in. The UPS is also important for ensuring that the hospital’s computer systems remain up and running during a power outage, as losing access to patient records and other critical data can have profound consequences.
Maintaining reliability
Both the isolated power supply and the UPS play a critical role in ensuring the reliability and safety of a hospital’s electrical infrastructure. The isolated power supply ensures that critical medical equipment receives the power it needs to function properly, while the UPS provides a back-up power source to keep the hospital’s electrical systems running in case of a power outage. Together, these two components help to keep patients safe, and provide continuity of care, even in the event of a power interruption.
Interconnected and integrated
It is also worth mentioning that both isolated power supply and UPS are also interconnected and integrated to provide complete protection and redundancy of the power supply. The UPS systems are connected to the main utility power, and act as a filter for the power supply to protect the equipment and, at the same time, provide temporary power in the event of a power outage. An isolated power supply – on the other hand – is connected to the UPS to provide a clean and stable power supply to the equipment. In many cases UPS and IPS systems are integrated together to provide monitoring for local BMS (Battery Management System) equipment and / or theatre panels.
Why healthcare estates need these interconnected power systems
Hospitals need an IPS and UPS for several reasons:
Patient safety: Medical equipment, such as surgical equipment and life support systems, are critical for patient care and safety. An isolated power supply provides a stable power source for this equipment, which helps to prevent damage, and ensures that the equipment is always in a safe state. A UPS provides a back-up power source during power outages so that critical equipment can continue operating without interruption.
Equipment protection: Medical equipment is often expensive and sensitive to power fluctuations. An isolated power supply helps to protect this equipment from damage caused by power fluctuations, and a UPS helps to protect it from damage caused by power outages.
IT infrastructure: Hospitals rely heavily on IT systems to manage patient records, monitor vital signs, and communicate with other healthcare providers. These systems require a continuous and reliable power source, which a UPS provides.
Compliance: Many countries, including the UK, have regulations and standards such as HTM 06-01 that require hospitals to have an isolated power supply and an uninterruptible power supply in place to ensure continuity of patient care, minimise the risk of injury or damage to patients, equipment, and personnel, and ensure compliance with relevant legislation.
Continuity of care: Power outages or voltage fluctuations can cause a disconnection in services, which could be devastating for a hospital setting, where continuity of care is crucial. IPS and UPS systems help ensure that these interruptions are minimised or avoided entirely, allowing the hospital to continue providing care to patients.
IPS, UPS, and HTM 06-01
HTM 06-01 is a British standard which provides guidance on the design, installation, commissioning, and maintenance, of the electrical infrastructure of a healthcare estate – and specifically electrical power distribution and control, including emergency lighting, UPS, and IPS. The standard establishes guidelines for the design, installation, testing, and maintenance of the electrical power distribution and control systems in healthcare premises. These guidelines include provisions for the use of IPS and UPS in healthcare facilities, including requirements for the sizing, selection, and installation of these systems, and their integration with the overall electrical power distribution system.
Maintenance and environmental conditions
It is important to maintain both the isolated power supply and UPS to ensure that they are working efficiently and effectively. Regular maintenance, inspections, and testing, should be performed to ensure that the equipment is functioning properly, and that any issues are identified and resolved in a timely manner. These regular maintenance procedures can help to prevent costly breakdowns, and prolong the life of the equipment.
Environmental inspections are typically part of a service visit. This is because the environment in which IPS and UPS are situated can significantly affect the unit’s longevity. For IPS systems, higher ambient temperatures cause a rise in temperature around the medical isolation transformer, and temperatures above 70 °C could cause potential damage to the transformer. Left undetected, the transformer will need replacing or result in a failure of supply. An IPS known to be working in a higher ambient temperature should be de-rated by up to 40% to prevent this from happening
UPS systems, on the other hand, must be in a temperature-controlled room with an ambient temperature of a maximum of 20-25 °C Elevated temperatures can cause batteries to prematurely fail, swell, and eventually split, and a leaking battery poses a fire risk, as well as a risk of UPS failure.
Dry and dust-free
Both IPS and UPS equipment must be kept dry and dust-free. High moisture in the environment causes condensation to build up, which can in turn cause boards to corrode and result in corrosion on battery terminal posts. Dust can lead to short-circuits and fire. It is recommended in areas where UPS and IPS are installed to also have an air-conditioning (AC) unit to regulate and control the ambient temperature. IT departments are also recommended to check the location of the external air intake vents, and to add a filtering system to reduce the level of dust entering the room.
In conclusion, the relationship between an IPS and a UPS is especially important in maintaining and providing a stable power supply to a hospital’s electrical infrastructure. They work together to provide complete protection and redundancy of the power supply, maintain critical medical equipment, and keep the hospital’s electrical systems running even in the event of a power outage.
Allan Jackson
Healthcare continues to be one of Power Control’s largest divisions, and last November the company appointed Allan Jackson as its new Southern Healthcare manager. With over 13 years’ experience working in the sector, he is responsible for working with key partners, and developing new business in the healthcare market. While his knowledge sits mainly with isolated and uninterruptible power supplies, his expertise also extends right across a hospital’s electrical infrastructure