There are many key decisions that health care system administrators face when replacing and deploying mobile workstations. Setting a reasonable budget and timeline, training staff, optimizing software builds and packages, and choosing compatible hardware that will empower your users all start with the platform choice. Choosing a laptop, thin client, small form factor PC, or All-in-One computing system will have a dramatic effect on the type of power system you choose for your cart, and will effect runtimes and mobility of these systems.
So, how do you determine what power system is appropriate for your situation? First, we need to consider the hardware components involved and how long we would like it to run. WARNING: A little math is involved.
By Jerry Faiella, VP of Sales & Marketing, JACO Inc.
There are many key decisions that health care system administrators face when replacing and deploying mobile workstations. Setting a reasonable budget and timeline, training staff, optimizing software builds and packages, and choosing compatible hardware that will empower your users all start with the platform choice. Choosing a laptop, thin client, small form factor PC, or All-in-One computing system will have a dramatic effect on the type of power system you choose for your cart, and will effect runtimes and mobility of these systems.
So, how do you determine what power system is appropriate for your situation? First, we need to consider the hardware components involved and how long we would like it to run. WARNING: A little math is involved.
How Much Power is Required to Run the Workstations?
Determine how much power is drawn from your hardware components, given an average load. Be sure to include any powered accessories, such as scanner systems, printers, or charging devices that may be run from the cart. We’ll call this number POWER, and it’s measured in watts.
How Long Do I Need the Workstations to Run?
Decide how long you would like the cart to run for. Most places look for full shift runtime, but that could be 8 hours or 12 hours depending on your organization. We’ll call this number TIME and measure it in hours.
POWER x TIME = WATT HOURS
This number, expressed in Watt Hours, allows you to compare your hardware and runtime needs across many different power systems, from SLA to Lithium Ion to Lithium Iron and whatever new technology arises. Let’s run through a few examples:
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Thin Client and LED Monitor.
Both a thin client and an LED monitor are low power devices, and in this example, we look in the documentation and see that the thin client has a power draw of 20 watts and the LED monitor also has a power draw of 20 watts.Assuming we want it to run for a total of 8 hours, we arrive at this equation:
(20W + 20W) x 8 Hours = 320 Watt Hours
In this instance, you would want to purchase a power system with greater than 320 Watt Hour capacity, and may want to consider something in the 500 watt hour range to account for some cell degradation as the power system ages and to improve the lifespan of the power system (more on this later).
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Laptop with LED Display and Barcode Scanner.
Many laptops are very energy efficient, and models that consume 25W or less are available.Combining that with a barcode scanner that uses 4 watts, and a runtime of 6 hours gives us:
(25W + 4W) x 6 Hours = 174 Watt Hours
In this case, we would probably want to purchase a smaller power system, on the scale of 250 watt hours, for the cost savings.
Now that we are able to determine just what size power system we will be looking for, let’s take a look at a few of the other qualifications you’ll want to consider in a power system.
What type of battery power technology is available, and what are the benefits of each?
Many older power systems are based on Sealed Lead Acid (SLA) battery chemistry. These systems are relatively cheap on initial purchase, and can provide greater watt hours of runtime, however they come with a significant downside. The lifespan of many of these products are very low, on the scale of 18-24 months, and often suffer from “Deep Discharging” in which the power levels are drained too low, and the integrity of the cell is adversely affected.
Many of these systems were replaced with Lithium Ion Phosphate cells, which provide protection against “Deep Discharging” and offer a much greater lifespan. However, this came at the cost of runtime and price. Lithium Ion is also difficult to dispose of properly.
More recently, Lithium Ferrous Phosphate (LiFePO4) cells have arrived on the market. Also known as Lithium Iron, they take the benefits applied to Lithium Ion cells, such as eliminating the “Deep Discharging” problem, and added additional improvements. They run at a lower temperature, improving runtime and lifespan, along with recharge times. They are also environmentally friendly, with Environmental Graffiti stating, “This non-toxic chemical is a significant improvement over the older Li-ion (lithium ion) rechargeable battery made of lithium cobalt dioxide LiCoO2.”1
What can I do to improve the lifespan of my power system and other computing hardware?
The first thing you can do may seem obvious, but selecting the best battery system that you can, with the longest lifespan will help the most. From there, there are several things you can do to help improve the life even more. Try to avoid completely discharging the cell as much as possible. Cell life spans are measure in cycles, and a complete discharge and recharge counts as 1 cycle, whereas a 50% discharge with recharge only counts for 1/2 cycle. The more you keep your power system charged and not running on battery power, the longer the power system will last.
The other thing you can do relates more to computing hardware in general, but keeping things clean and free of dust, particularly fans and vents, will help significantly. Heat is the biggest problem that electronic components face, and a blocked vent or fan will stop it from dissipating the heat properly. Significant dust buildup is often the cause of these issues.
What can I do to reduce mobile cart downtime?
By selecting components that are 60601 Certified, you are able to use them in patient treatment areas, reducing the amount of time spent moving the cart to designated areas. Most computer carts used in medical environments carry this designation, but it is always good to verify it before purchase.
Select quality hardware and components that are designed to stand up to the rigorous environments encountered in hospitals every day. The stronger the materials and components are, the less time you’ll need to spend replacing parts that are broken or misused.
Also consider the warranty of the products you purchase, and the response time of the manufacturer. Products with longer warranties are usually less likely to experience problems, and if that’s combined with a fast response to any problems that do arise, you should be able to get the workstation back up and running in a short amount of time.
JACO Inc. is a US manufacturer of mobile carts and health care equipment who design, engineer and manufacture products with the certified 60601 designation and have been in business for 40 years. Visit us at www.jacoinc.com or contact us at 1-800-649-2278.
Sources:
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http://www.environmentalgraffiti.com/energy/news-environmentally-rechargeable-lithium-iron-battery-better-lithium-ion-battery
