Hospitals and imaging centers invest millions of dollars in complex, sophisticated medical-imaging equipment that is highly sensitive to power problems and fluctuations. According to Michael Stout, engineering manager of Falcon Electric (Irwindale, Calif), medical-imaging systems are “a system of interconnected scanners, sensors, computers, distributed data-storage devices, and networking devices.” Adds Mike Habibi, technical support manager of MGE UPS Systems (Costa Mesa, Calif), these systems are very sensitive to electrical noise, power shortages and glitches, and brownouts.

These expensive systems, therefore, need to be protected to prevent damage and degradation. The additional cost of protection, however, is often a factor in the lack of proactive power protection. But as Ron Wodka, medical business development manager at Tripp Lite (Chicago), explains, the cost spent on medical-imaging equipment versus power-protection equipment is like an insurance policy; replacing power-protection equipment is much cheaper than replacing an imaging device.

The Cause

The reasons for poor power quality are multiple?from natural occurrences (such as lightning, heavy winds, and ice or snow on power lines) to unnatural occurrences (including utility company failures, overburdened power grids, downed power lines, and hospital generators and elevators). Blackouts, brownouts, power surges and spikes, and line noise are the result, which, in turn, cause power fluctuations that last anywhere from hours to mere milliseconds.

“Surges often go unnoticed, often lasting only 1/120th of a second, but they are much more common and destructive than [facilities] might think,” Wodka says. Also, Kevin Harris, marketing manager for TEAL Electronics Corp (San Diego), explains, “The infrastructure often does not keep up with the growth.” In other words, with more rooms and additions to a hospital, the power requirements needed for the extra space and equipment oftentimes is not considered.

According to Judith Russell, a consulting electrical engineer for PowerLines (West Hartford, Conn), the hospital environment tends to be poor, electrically speaking?hospitals often are built in stages, with wings and renovations added later, causing many potential problems with the electrical system.

The Effect

Resulting issues from poor power quality, regardless of the cause, range from financial considerations to data protection to patient safety. Destruction of the system from power surges or other causes can be very costly with expensive component replacement and service calls. Spikes, sags, and even brownouts can produce long-term system degradation that is equally as costly. Disruption to the system causes downtime and loss of productivity.

“Half of US corporations rate their downtime costs at more than $1,000 per hour, and 9% of corporations estimate the costs to be more than $50,000 per hour,” says Bob Thomas, general manager of Rx Monitoring Services (Bedford, NH), adding that the loss of revenue for freestanding imaging centers might be $2,000 per hour or more due to loss of productivity. The company gathered this information based on an internal survey that was conducted by graduate students at New Hampshire College (Manchester, NH). Thomas adds that the cost of a possible lawsuit could be even higher if a patient’s procedure already has begun in, for instance, a cardiac catheterization lab. If the system is disabled due to power problems, the patient would need to be rescheduled. Legal and financial problems would occur if a physical complication with the patient occurred between the original visit and the time that the patient could be rescheduled.


American Power Conversion (APC of West Kingston, RI), a manufacturer of power-protection equipment, now offers complete physical protection of medical-imaging equipment and data centers with its recent acquisition of NetBotz (Austin, Tex), a manufacturer of environmental monitoring equipment. APC always has offered physical protection against power damage (for example, surges, sags, and brownouts). Now, with the addition of the NetBotz product line, APC offers protection against environmental damage (for instance, heat, humidity, and pipe leakages) as well as human errors. “By obtaining data from sensors and monitoring equipment, the NetBotz product assesses the severity of threats and provides notification of events,” says Peter Poulin, VP of North American sales at APC.

Because maintaining digital medical-imaging records is critical for patient care, the imaging data center’s availability is of utmost importance. Any factor that contributes to the loss of records, whether temporary or permanent, needs to be reduced. In addition to the power-protection devices offered by APC, NetBotz offers the monitoring of the data center to detect physical threats. Poulin explains that the system detects and notifies when user-definable thresholds are met, such as an extreme rise in temperature over a short period of time, fluid on the floor, the presence of a person in the room at an abnormal hour, or the presence of helium in an MRI room.

How does it work? A base appliance is attached to the network, while sensors are attached to detect the physical threats. The hospital then defines the threshold of acceptable events (such as, temperatures, sounds, and movements), defines who will be alerted of the events, and how the alerts are transmitted (for example, via phone call or page). Additionally, the NetBotz product offers diagnostic information, such as pictures of the room or graphs of the temperature fluctuations.

The 24/7 monitoring of critical spaces like a data center provides an extra level of security that, according to Poulin, will let the hospital “know proactively before the network goes down.” Good thinking!

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MGE’s Habibi adds that with poor power quality, not only can the equipment be damaged, but the readouts can be affected as well, which might require the test to be redone, thus increasing the workload. Additionally, power fluctuations can produce possible imaging errors. PowerLines’ Russell states that if the imaging equipment is not accessible and up and running, there are potential costs to the patient in rescheduling and misdiagnoses, not to mention the downtime for rebooting or placing service calls.

Providing Protection

A plethora of power-protection devices exist, such as uninterruptible power supplies (UPSs), power conditioners, surge suppressors, isolation transformers, and voltage regulators, all with multiple sizes and functionalities for specific applications in imaging equipment:

  • Online UPS devices provide continuous power for sensitive and critical equipment.
  • Power conditioners often include isolation transformers and surge protectors, but do not provide battery backup. Habibi says that UPS devices and power conditioners help to “prevent premature component degradation,” resulting in longer equipment life and less downtime.
  • Surge-suppression devices protect against power surges and line noise. According to Russell, surge suppressors are a “low-cost insurance policy for medical-imaging systems.”
  • Isolation transformers generally provide line isolation, noise filtering, and surge suppression. Jim Ference, healthcare market manager of POWERVAR Inc (Waukegan, Ill), says that transformers also isolate the patient from leakage current, which could cause electrical shock and, therefore, be very dangerous to the patient.

What to Protect

At what level should imaging equipment be protected? Viswas Purani, director of emerging technologies and applications at American Power Conversion (APC of West Kingston, RI), provides a simple list of recommendations based on the critical application of the modality and the facility’s available budget:

  • Entire room/facility protection (CT, MRI, PET, and other radiology rooms deploying high-end floor-mounted modalities) requires a large UPS in the range of 300?500 kilovolt amperes (kVA);
  • Entire modality protection (CT, MRI, PET, SPECT, and other floor-mounted modalities) requires a medium-size UPS in the range of 50?250 kVA; and
  • Protection of only the electronics and computer systems of a modality requires a small UPS in the range of 5?10 kVA. “In situations where budget is a major constraint,” Purani advises, “at a minimum, the electronics and computer systems of a modality should be protected.”

Ask the Experts

To determine potential power-quality risk or to uncover the source of a current power problem, a professional power-quality analyst or engineering company should conduct either a risk analysis or a power-quality audit. In general, the power-quality professional?who is experienced in gathering and reading the data to make appropriate protection recommendations?uses a power-quality monitor or analyzer, which typically is not simple to analyze.

Thomas of Rx Monitoring says that by spending some money to gather data, the hospital will know where the risks are and what needs to be protected.

Additionally, TEAL’s Harris says that the new direction in servicing equipment is through remote monitoring. Normally, when such equipment as a CT or an MRI experiences performance problems or is completely inoperable, and after minor troubleshooting occurs at the hospital, the facility places a service call and parts are ordered.

At this point, the hospital has potentially lost a few days of revenue, and patient rescheduling is required if the equipment is completely unavailable. With remote monitoring, diagnosing the problem could occur much sooner, and potentially a day of downtime could be saved. Remote monitoring adds value to the system, Harris says: “It pays for itself with [even] one less service call.”

Get Your Power Here!

The power market is surging with products. The following list shines the light on what is available, including brief descriptions, to best serve your facility’s needs.

American Power Conversion (

  • APC InfraStruXure?customized, modular systems with fully integrated power, cooling, and environmental management for data centers
  • APC InfraStruXure Manager?a 24/7 remote-monitoring service with alarm notification, online reports, and user-definable escalation procedures
  • APC Silicon, Symmetra MW, and Symmetra PX UPSs?for larger CT/MRI modality protection
  • APC Smart-UPS?for smaller desk-mounted and portable modalities

Falcon Electric (

  • SG Series Online UPS?double conversion; with voltage regulation and extended battery operation; available from 800 VA to 6 kVA; “intelligent microprocessor design that supports advanced communications capability,” says Michael Stout of Falcon Electric

MGE UPS Systems (

  • Galaxy 3000 and 4000 UPS?online double-conversion technology; available from 40 kVA to 75 kVA; protects against over- and under-voltage conditions; with voltage regulation and surge protection
  • Galaxy PW UPS?online double-conversion technology; available from 100 kVA to 225 kVA; with a modular design and battery self-testing; protects against over- and under-voltage conditions; with voltage regulation and surge protection
  • EPS 6000, 7000, and 8000 UPS?online double-conversion technology; available from 225 kVA to 500 kVA; with optional power-monitoring system; protects against over- and under-voltage conditions; with voltage regulation and surge protection
  • Power Sure 700 Power Conditioner?protects against over- and under-voltage conditions; with voltage regulation and surge protection; no power-outage protection

NetBotz, an APC company (

  • NetBotz 320, 420, or 500?monitoring system to sense possible environmental, visual, and audio threats; available in three versions, depending on the size and level of functionality
  • NetBotz Central?management platform to view all NetBotz monitoring appliances from a central location
  • NetBotz Surveillance?add-on software application that provides a visual record of who enters specified areas and what they do

Post Glover LifeLink (

  • Mark IV LIM (Line Isolation Monitor)?isolated power-monitoring system to protect patients and personnel against leakage current or shock hazards; predictive indication that a potential problem might occur; allows staff to “safely remove the patient before a hazardous situation occurs, and the system maintains power to critical equipment even during an alarm situation,” explains Keith Van Kerckhove, engineering manager of Post Glover LifeLink

PowerLines (

  • Engineering and Consulting Services?reviews and analyzes power-monitor datasets, specializing in medical-imaging equipment; recommends types of solutions


  • ABCE UPS Series?for ultrasound, PACS, and single-phase applications; with isolation transformer; available from 350 VA to 1440 VA
  • ABCDEF UPS Series?online; for X-ray, CT, and MRI applications; with isolation transformer and voltage regulator; available from 2.4 kVA to 18 kVA
  • ABC Power Conditioner Series?with isolation transformer; available from 78 VA to 2400 VA

Rx Monitoring Services (

  • Remote Power Quality Analysis?proactive monitoring for baseline data using RxMS Power Analyzers (EPA1000 and EPA2000); provides power-quality reports and makes unbiased recommendations to facilities for optimal performance

Staco Energy Products Co (

  • UniStar II UPS?single-phase, online, double-conversion technology; available in 6 kVA and 10 kVA
  • Automatic Voltage Regulators?protects against voltage swings; with modular construction; also with power-conditioning and surge-suppression options

TEAL Electronics Corp (

  • PDU-XT150?power-distribution unit with high-energy filtering and surge suppression; for high-power medical-imaging applications; available for input voltages from 200 VAC to 480 VAC; reduces cost of electrical-site preparation in a small footprint design to save floor space
  • Custom Power Subsystems?custom-designed power subsystems that integrate AC, DC, distribution, filtering, suppression, monitoring, and voltage regulation
  • TEALwatch?Internet-based power monitor that uses standard Web browser software for 24/7 remote monitoring; easy to use and fully programmable

Tripp Lite (

  • HC350SR?inverter/charger/UPS/isolation transformer-type of power supply for mobile medical workstations; converts DC battery power to pure AC power for flat-panels and PCs on mobile medical carts; remote-control display provides tone and visual LEDs that allow viewing of the charging status and amount of power remaining
  • Smart Series Online UPS Systems?for critical PCs and networks, with automatic voltage regulation (AVR) and surge protection; provides “guaranteed constant reliable pure power,” says Ron Wodka of Tripp Lite
  • OmniSmart series Line Interactive UPS Systems?for noncritical areas; with AVR and surge protection; prolongs equipment life
  • PowerAlert Software?provides power monitoring and management of UPS systems
  • Isolation Transformers?where battery backup is not required, but high isolation, low-leakage current, and surge suppression is needed
  • ISOBAR-ULTRA-HG Surge Suppressor?filters line impurities; robust metal housing; with diagnostics
  • SPS-615-HG Surge Suppressor?lower cost; does not filter; fully grounded

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Sometimes, learning from the experience of others can be the best way to determine what will work best for you. Here, staff members from facilities, manufacturers, and an energy consultant briefly share their power-protection plans.

Two Reasons for UPS

The Loyola University Medical Center (Maywood, Ill) uses the Comet UPS (previous version of the Galaxy 4000) from MGE UPS Systems to protect the center’s PACS and its clinical information system. Without a UPS device, the effects could be “catastrophic,” says Dan Valdez, manager of the service support group in the center’s IT department. Grief for both patients and personnel would result without constant system availability made possible by the UPS device. Valdez concludes that the UPS is crucial for the business, and the business is to take care of the patients.

The same is true at Gateway Health System (Clarksville, Tenn). Corey Watts, technical support coordinator for Gateway Health, explains that the medical center uses one EPS3000 UPS from MGE to protect both its PACS and its digital cardiac catheterization lab system?in addition to smaller rack-based UPS devices for an additional layer of protection. Watts emphasizes that the protected systems cannot be out of service at any time. “A great deal of time and effort are involved in such projects as establishing data centers, and people often forget to consider network bandwidth and power requirements,” he continues. “[The center] uses medical imaging in the emergency department 24/7. We don’t want to lose any data.”

Specific Product, Specific Solution

When releasing the Upright MRI, the world’s only stand-up MRI system, Fonar (Melville, NY) decided to also offer a cost-efficient, specially designed power-protection solution to customers. Mark Gelbein, systems project manager at Fonar, explains that the company was looking for a solution to compensate for voltage drops, brownouts, and fluctuations. Staco Energy Products Co (Dayton, Ohio) provided just that solution.

Upon request, Staco Energy modified its current voltage regulator to work specifically with Fonar’s Upright MRI to continuously monitor and adjust the voltage. In addition, the MRI system also uses Staco’s UniStar II online, single-phase, double-conversion UPS device to protect and provide battery backup to the monitors and the patient table.

A Consultant in Action

Judith Russell, a consulting electrical engineer for PowerLines (West Hartford, Conn), was requested by an imaging manufacturer to help diagnose a power-quality problem for a hospital* in Philadelphia. Power problems of an unknown origin were causing multiple “nuisance” types of errors in the X-ray generator of a radiology room.

After performing a survey and monitoring the power, Russell determined that the local utility company was switching banks of capacitors, resulting in low-frequency voltage transients, which were outside the control of the hospital. Rather than recommending a power conditioner, filter, or surge suppressor, Russell found that the equipment was able to operate at a lower voltage. By lowering the voltage?from 480 volts alternating current (VAC) to 400 VAC?and with the installation of an isolation transformer (a low-cost, simple-to-install voltage-conversion unit), the power problems with this equipment were completely resolved.

Nine months later, however, another power problem was discovered in a completely different imaging system installed at the same hospital. A CT scanner’s X-ray generator was being damaged due to unknown power problems. Russell determined that the source of the power problems were due to the same utility voltage transients identified earlier in the year. This time, however, a low-cost solution was not available.

After evaluating the possible solutions, the installation of a UPS device was recommended to resolve the power problems with this particular piece of equipment. In the interim, while a UPS was being ordered, delivered, and installed, the hospital needed to rent a diesel generator to operate the CT unit from a separate power source not affected by the utility transients.

Both of these situations represent power problems that are typically found in hospitals: one problem?in this case, the utility company causing voltage transients?produced multiple results. Most of the systems within the facility were not affected; however, some equipment produced errors, and some equipment was actually damaged by the power problems.

“The types and magnitudes of such problems are difficult to characterize,” Russell explains, “and equipment susceptibility is difficult to predict, hence, the importance of working with a power-quality engineer who is familiar with imaging equipment to assist in the diagnosis and resolution of power-quality problems in the medical-imaging environment.”

* This hospital has remained nameless for legal reasons.

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Nici Lewis is a contributing writer for Medical Imaging.