Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (4)

Refer to the Previous Article: Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (3)

Vented Nickel-Cadmium Batteries

Just like the name suggests, these batteries are a vented (flooded) type, where the positive plate is made of nickel hydroxide and the negative plate is made of cadmium hydroxide. These batteries are often preferred because they:

• Have a high cycle count
• Can be charged very fast
• Have a long shelf life

However, these batteries have the following drawbacks:

1. The NiCd batteries have lower voltages (1.2 V instead of 2 V for lead-acid batteries), which could be a problem for space. For a 120 V system, we would need 60 lead-acid cells, but 100 NiCd cells.
2. Cadmium is toxic, so these batteries are not easy to dispose.
3. NiCd batteries have memory, which means they remember the capacity delivered the last time and don’t deliver more than that. Because of this, they need to be discharged to lose the memory and then fully charged again.

IEEE has developed a standard for this type of battery: IEEE 1106-2015, Recommended Practice for Installation, Maintenance, Testing, and Replacement of Vented Nickel-Cadmium Batteries for Stationary Applications (https://standards.ieee.org/findstds/standard/1106-2015.html).

As with other kinds of batteries, personal protective gear, such as goggles, gloves, and aprons, are recommended when servicing the NiCd batteries.

IEEE 1106-2016 recommends a quarterly inspection, which is the same as the vented lead-acid batteries’ monthly inspection:

A visual inspection of:

1. The general condition of the area
2. The battery cells, looking for cracks
3. The electrolyte levels
4. The battery terminals for corrosion

A measurement of:

1. The float voltage at the battery terminals
2. The float current
3. Room or area temperature and ventilation

There is a semiannual inspection as well. This inspection encompasses what the quarterly inspection requires and adds cell voltage measurements. The yearly inspection also requires looking at the condition of the cable connections and measuring the resistance.

A list of simple corrective actions to a few abnormalities

The NiCd batteries can be submitted to a high-rate charge. Normally, they are charged at around 1.4 to 1.47 V per cell, but in a high-rate charge, the voltage can go to 1.55 V for a maximum of 1.8 V.

A NiCd battery is more tolerant of higher temperatures. The NiCd battery life and temperature correlation is shown below.

The relative correlation of nickel-cadmium (NiCd) battery life expectancy and temperature.

NiCd batteries, if operated at 20 to 25°C (68 - 77°F), can last a long time. Their capacity drops slowly, reaching 80% after 20 years. Even after that, they can be used in less-demanding applications.



Summary: The Importance of Design


Maintenance is especially important for mission critical systems because of the importance of the reliability of these systems. Indeed, maintenance does not start when problems with the equipment arise; rather, maintenance starts with the design of the systems. The design professional always needs to keep maintenance in mind when designing electrical systems, and the same goes for battery systems.

Keep the following tips in mind when designing and specifying batteries in mission critical facilities:

• Decide early, in conjunction with the owner, what type of battery to use. Choosing the battery type early helps with nailing down the design and operation conditions of the battery system.
• Design a cooling system in accordance with the manufacturer’s recommendations. As mentioned, the ambient temperature plays a big role in the battery lifespan.
• Design a ventilation system to properly refresh the air in the area to not allow hydrogen concentration in the area.
• Design proper clearances around the battery racks.
• Design proper containment in case of a leakage of the battery solution.

After the system (or facility) is up and running, it is critical to make sure that the design conditions mentioned above are enforced. It is also critical to follow IEEE recommendations for weekly, monthly, and yearly inspections (add a semiannual inspection for NiCd batteries). A visual inspection, as simple as it might seem, is very important to catch early what could become a serious malfunction.


It is best for the maintenance team to prepare a standard form for each type of inspection. These forms could have boxes for check marks and spaces for notes where certain conditions observed can be explained. Having a log of the inspections helps in tracking certain conditions and compiling a plan of action if the conditions deteriorate.

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The team exists to provide an interactive environment and opportunities for members of data center and facilities' engineers to exchange professional views and experience, through various training courses, industry events and technical seminars. We prepare the engineers and IT personnel to face any challenges in data centers and critical facilities of any size, in any location.


For other design considerations / topics in data center and critical infrastructure, please visit 


(1) Site Selection,
(2) Space Planning,
(3) Cooling,
(4) Redundancy,
(5) Fire Suppression,
(6) Meet Me Rooms,
(7) UPS Selection,
(8) Raised Floor,
(9) Code & Standards,
(10) Transformers and Harmonic Distortion,
(11) Multi-mode UPS Systems,
(12) Electrical Rooms,
(13) Generator Systems,
(14) Generator Fuel Systems, 
(15) Battery Systems, etc.

Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (3)

Refer to the Previous Article: Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (2)

Valve-regulated Lead-acid (VRLA) Batteries

VRLA batteries currently are very popular. They are known as "nonmaintenance" batteries, mostly because of the fact that they are sealed and employ a "recombinant technology." The fact that the battery is sealed ensures the preserving of the electrolyte, no matter the position of the battery cell (you can even turn it upside down). Recombinant technology means that the oxygen released from the positive plate ends up in the negative plate, where it recombines with hydrogen and turns into water. This process preserves the battery water.

Just as it has for vented batteries, IEEE has developed a standard, 1188-2005, IEEE Recommended Practice for Maintenance, Testing, and Replacement of VRLA Batteries for Stationary Applications (https://standards.ieee.org/findstds/standard/1188-2005.html).

Even though VRLA batteries are sealed, there are always dangers associated with installing and maintaining batteries. Only trained and knowledgeable personnel should work around batteries. In addition, unauthorized personnel should not have access to the batteries. The battery area should not be used as storage for tools or anything else. All personnel should use personal protective equipment, such as goggles, gloves, and safety shoes, while working on batteries.

The table shows typical steps to be taken when adverse situations are witnessed.

Just as with vented batteries, inspection is an important part of maintenance. IEEE recommends monthly, quarterly, and yearly inspections. But this recommendation is for general use. For mission critical facilities or processes, there needs to be a weekly inspection as well.

The monthly inspection for VRLA batteries is more or less the same as the one for vented lead-acid batteries. This inspection includes the following areas -

A visual inspection of:

1. The general condition of the area. The area (room) should be maintained as clean as possible so that dirt or excessive dust does not cover the battery cells. Unclean equipment is harder to assess during a visual-only inspection.
2. The battery cells, looking for cracks. This inspection is important because a crack in the cell’s outer shell could allow the electrolyte to leak.
3. The battery terminals for corrosion. Corrosion of the battery terminals will increase the resistance of the connection, thereby decreasing the amount of current supplied by the battery system.

A measurement of:

1. The float voltage at the battery terminals. If the battery system performs at a float voltage outside the manufacturer’s recommended range, the battery’s life expectancy would be adversely affected.
2. Room or area temperature and ventilation. The temperature is important because it affects the battery’s life expectancy. Ventilation is important because proper movement of the air mitigates high concentrations of hydrogen, which is a byproduct of chemical processes in the battery cells. High concentrations of hydrogen in the air significantly increase the risk for explosions.
3. The float current of the string. A high float current would adversely affect the battery life, as it increases the temperature in the cell.

The quarterly inspection includes measurements of the following:

1. The cell’s internal Ohmic values. Care should be taken to use the same method each time so that a credible baseline is set. If the Ohmic values change drastically (30% to 50%), a battery replacement might be warranted.
2. The temperature of the negative terminal of each cell. A higher temperature than other cells could indicate a higher charging current. Higher temperatures adversely affect the battery life.
3. Cell voltages. Both high and low voltages could be problematic. Prolonged low voltage-lower than the manufacturer’s limit-without an increase in temperature could indicate an internal problem. Prolonged high voltage-higher than the manufacturer’s recommended limit-could impact the battery life by accelerating the dryout.

The yearly inspection is then limited to measuring the following:

1. Cell-to-cell and battery terminals resistance. If the value is 20% or more than the baseline, corrective actions should be taken, such as cleaning the connections and retorquing.
2. Battery-charger ripple current. It could impact the battery temperature.

Next Article:
Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (4)

About us

SMA connects IT, Facilities and Design. For the other design considerations, please visit 

(1) Site Selection,
(2) Space Planning,
(3) Cooling,
(4) Redundancy,
(5) Fire Suppression,
(6) Meet Me Rooms,
(7) UPS Selection,
(8) Raised Floor,
(9) Code & Standards,
(10) Transformers and Harmonic Distortion,
(11) Multi-mode UPS Systems,
(12) Electrical Rooms,
(13) Generator Systems,
(14) Generator Fuel Systems, 
(15) Battery Systems, etc.

All topics focus on key components and provide technical advice and recommendations for designing a data center and critical facilities.

Strategic Media Asia (SMA) is one of the approved CPD course providers of the Chartered Institution of Building Services Engineers (CIBSE) UK. The team exists to provide an interactive environment and opportunities for members of ICT industry and facilities' engineers to exchange professional views and experience.

Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (2)

Refer to the Previous Article: Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (1)

Inspection


The maintenance of the batteries in mission critical facilities is especially important. When maintained regularly, batteries will perform according to design to support the critical systems, ensuring the continuity of power. Maintaining the batteries also elongates their life, resulting in lower operation costs. But the first step of maintenance is to inspect. By first inspecting and then assessing, we can develop a plan for remediation.

Let’s look at each battery type separately. IEEE has developed separate standards for just this reason.


Vented Lead-acid Batteries


The most routine inspection for this type of battery is a visual inspection. IEEE has developed a standard, 450-2010, IEEE Recommended Practice for Maintenance, Testing, and Replacement of Vented Lead-Acid Batteries for Stationary Applications (https://standards.ieee.org/findstds/standard/450-2010.html). This standard is a very good guide for the operations staff to create a maintenance procedure.

The monthly inspection, as recommended in the IEEE 450-2010 standard, includes the following:

A visual inspection of:

1. The general condition of the area. The area (room) should be as clean as possible so that dirt or excessive dust does not cover the battery cells. Unclean equipment is harder to assess during a visual-only inspection.
2. The battery cells for cracks. This step is important because a crack in the cell’s outer shell could allow the electrolyte to leak and the battery to discharge.
3. The electrolyte levels. A significant drop in the electrolyte level means that the specific gravity of the electrolyte has increased. A greater specific gravity would impact the life of the battery.
4. The battery terminals for corrosion. Corrosion of the battery terminals will increase the resistance of the connection, thereby decreasing the amount of current supplied by the battery system.

A measurement of:

1. The float voltage at the battery terminals. If the battery system performs at a float voltage outside the manufacturer’s recommended range, the battery’s life expectancy would be adversely affected.
2. Room or area temperature and ventilation. The temperature is important because it impacts battery-life expectancy. Ventilation is important because proper movement of the air mitigates high concentrations of hydrogen, which is a byproduct of chemical processes in the battery cells. High concentrations of hydrogen in the air significantly increase the risk for explosions.

The recommended quarterly inspection includes the following:

A measurement of:

1. The voltage of each cell. Lower-than-recommended (by the manufacturer) voltage levels could have an adverse affect on the life expectancy of the battery.
2. The specific gravity of the cells’ electrolyte. One needs to keep in mind that specific gravity of the electrolyte increases in a full charge. It would be best if three measurements are taken: one on top, one in the middle, and one on the bottom of the cell. The average of the three values is the value to be used. If taking three measurements is not possible, taking a reading as close to the middle as possible is best. Note that it’s not necessary to measure the specific gravity of each cell in the battery string, rather only about 10% of the cells.
3. The electrolyte temperature of a few cells. If we have a 125 V battery system, we’d have 60 cells. It would suffice to check the temperature of six of them. The desired temperature is the one recommended by the manufacturer. If the electrolyte is at a higher temperature, a higher float current is required to maintain the cell voltage. Too high of a charging current could adversely affect the electrolyte composition, as more of the hydrogen and oxygen is being gassed. On the other hand, the lower temperature causes a smaller floating current, which in turn, slows the charging process.

Corrective actions are shown for some abnormalities in vented lead-acid and nickel-cadmium (NiCd) batteries.

There is also a yearly inspection that applies the quarterly inspection to all the battery cells, which is, therefore, much more involved. If abnormalities are observed during these inspections, there are corrective actions that can be taken. See Table 1 for some common corrective actions.

Of the abnormalities mentioned in Table 1, the room temperature and ventilation usually are set during the design. Total cost of ownership analysis is usually done by taking into consideration the optimal conditions so that the battery life is longest. The rule-of-thumb correlation between ambient temperature and lead-acid battery life, be it vented or VRLA, is as follows: battery life decreases by 50% for every 8°C above the normal temperature, which is 25°C (77°F).


Battery Life


Determining the battery life is important, especially in mission critical facilities. With proper maintenance, battery life could be predicted accurately, thereby avoiding any downtime. The most important factors affecting battery life are:

Ambient Temperature:
Keeping the temperature at 25°C (77°F) is optimal.

Maintenance:
Keeping the cell temperature in check; large temperature differences among the cells will affect battery life.
Keeping the cell voltage in check. The following should be corrected:

- Voltage below open cell voltage + 0.06 V
- Voltage above open cell voltage + 0.1 V (or 0.05 V for lead antimony).

Cycling:
The more discharges occur, the shorter the battery life.

Chemical Components:
Vented batteries can be lead-calcium, pure-lead, lead-selenium, or lead-antimony. All the outside factors affect the battery life differently, depending on the chemical composition of the battery.



Next Article:
Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (3)



About us

SMA connects IT, Facilities and Design. For the other design considerations, please visit 

(1) Site Selection,
(2) Space Planning,
(3) Cooling,
(4) Redundancy,
(5) Fire Suppression,
(6) Meet Me Rooms,
(7) UPS Selection,
(8) Raised Floor,
(9) Code & Standards,
(10) Transformers and Harmonic Distortion,
(11) Multi-mode UPS Systems,
(12) Electrical Rooms,
(13) Generator Systems,
(14) Generator Fuel Systems, 
(15) Battery Systems, etc.

All topics focus on key components and provide technical advice and recommendations for designing a data center and critical facilities.

Strategic Media Asia (SMA) is one of the approved CPD course providers of the Chartered Institution of Building Services Engineers (CIBSE) UK. The team exists to provide an interactive environment and opportunities for members of ICT industry and facilities' engineers to exchange professional views and experience.

Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (1)

 

Proper design, maintenance, and testing of battery system in mission critical facilities are crucial for business continuity and safety.

In these articles, we are going to

(1) Understand the need for reliable batteries in mission critical facilities;
(2) Explore the most common battery abnormalities that can be spotted through inspection; and
(3) Review simple steps that can be taken to find out battery problems.

When we say the systems are mission critical, it means "Power remains uninterrupted!". But this mission critical label does not apply to every single part of the facility. Some processes are more important to the business than others, and that is where the focus of the design lies. Certainly, designing for a mission critical facility can be challenging. There are many considerations in play. The system has to be very robust with no single point of failure.

Designing electrical systems, maintenance is an important factor, especially in deciding what battery to implement. Maintenance includes but not limits to the cost of replacement of a battery cell. It also involves the accessibility of the battery system, the ease of disassembly and reinstallation, the frequency of service, and the conditions needed in the actual environment (temperature, humidity, etc.).

The goal of maintenance is to prolong the life of batteries and to make sure the batteries perform as designed. Inspection is done to catch any abnormalities that could impact battery performance as well as long-term life expectancy. It is important to place the batteries in an environment that agrees with the manufacturer’s recommendations.


Battery Types


There are several types of batteries used for providing power to electrical systems. The most popular types of batteries being used nowadays are lead-acid and nickel-cadmium (NiCd). NFPA 110: Standard for Emergency and Standby Power Systems defines two types of lead-acid batteries:

Valve-regulated lead-acid (VRLA): A lead-acid battery consisting of sealed cells furnished with a valve that opens to vent the battery whenever the internal pressure of the battery exceeds the ambient pressure by a set amount.

A typical valve-regulated lead-acid (VRLA) battery used in an uninterruptible power supply (UPS) application

Vented (or flooded): A lead-acid battery consisting of cells that have electrodes immersed in liquid electrolyte. Flooded lead-acid batteries may have a provision for the user to add water to the cell and are equipped with a flame-arresting vent, which permits the escape of hydrogen and oxygen gas from the cell in a diffused manner such that a spark, or another ignition source, outside the cell will not ignite the gases inside the cell.

Although NFPA 110-2010 recognizes the usage of NiCd batteries for emergency systems, no definition is provided for such batteries. A definition can be found in IEEE 1106-2015: Recommended Practice for Installation, Maintenance, Testing, and Replacement of Vented Nickel-Cadmium Batteries for Stationary Applications (https://standards.ieee.org/findstds/standard/1106-2015.html).


Battery Uses


Mission critical facilities are not only the buildings that are critical to human life, such as hospitals, but also are facilities for business continuity, like data center. Many methods are employed to mitigate the risk of power outages. But, almost always, the risk mitigation relies upon batteries. Uses include:

Uninterruptible Power Supply (UPS) Systems: Batteries are used to back up power where UPSs are involved. While the power is processed and converted through the UPS to the load, the batteries are kept charged to provide the much-needed power to the critical system when normal power is out. Even though standby generators are most likely used as backup power, the batteries provide the critical power needed until the generators are able to receive load.

Standby Generators: Batteries are used to provide the initial crank to the generators as well as power the generator controls.

Controls: Batteries also are used to back up controls, especially when medium-voltage distribution is found throughout the facility. Nowadays, the operation of critical systems is more reliant on controls to avoid nuisance tripping and to enable fast-acting protection.

Emergency Systems: Batteries are widely used to back up life safety systems, such as exit lights. Exit lights normally are backed up by a 90-minute battery to allow people to recognize the way out of the building in case of a life-endangering situation. All of the above-mentioned uses (UPS, generators, and controls) could be part of an emergency system as well.



Next Article:
Battery Systems for Mission Critical Infrastructure - Design, Maintenance and Testing (2)



About us

SMA connects IT, Facilities and Design. For the other design considerations, please visit 

(1) Site Selection,
(2) Space Planning,
(3) Cooling,
(4) Redundancy,
(5) Fire Suppression,
(6) Meet Me Rooms,
(7) UPS Selection,
(8) Raised Floor,
(9) Code & Standards,
(10) Transformers and Harmonic Distortion,
(11) Multi-mode UPS Systems,
(12) Electrical Rooms,
(13) Generator Systems,
(14) Generator Fuel Systems, 
(15) Battery Systems, etc.

All topics focus on key components and provide technical advice and recommendations for designing a data center and critical facilities.

Strategic Media Asia (SMA) is one of the approved CPD course providers of the Chartered Institution of Building Services Engineers (CIBSE) UK. The team exists to provide an interactive environment and opportunities for members of ICT industry and facilities' engineers to exchange professional views and experience.

Four Monitoring Capabilities for Data Center Power Systems

The primary method that people use to measure the energy effectiveness of their data centers is power usage effectiveness (PUE). PUE compares the power used for computing capacity and the overall power used by the data center (PUE = Total Facility Power / IT Equipment Power). The inverse of PUE is data center efficiency, according to The Green Grid association.


Currently, the industry average PUE is reported to be around 2.0, but a number of new and proven data center infrastructure technologies are available to advance efficiency and reduce PUE to 1.5 or lower without compromising availability. There are 4 key actions data center managers can take with integrating monitoring capabilities into power systems that can help improve efficiency and advance PUE.

Monitoring Power Usage


With power densities and energy costs rising, the ability to monitor energy consumption is essential for advancing PUE. Where power is measured can have an effect on how efficiency is measured.

For a comprehensive picture of data center power consumption, power should be monitored at the UPS, the room power distribution unit (PDU), and within the rack. These data points should be consolidated and reported within an enterprise data center infrastructure management (DCIM) tool that can be shared by both facilities and IT management. DCIM tools (if specified early and fully integrated) can provide an overarching view of the data center, which will provide insights into how effectively or ineffectively the computing power of the data center is being used.


Specifically, measurements taken at the UPS provide a base measurement of data center energy consumption that can be used to calculate PUE and identify energy consumption trends. Monitoring the room PDU prevents overload conditions at the PDU and helps ensure power is distributed evenly across the facility.







The best view of IT power consumption comes from intelligent PDUs inside racks, which feature integrated monitoring and control capabilities to enable continuous power monitoring and feedback to the DCIM tool. Because rack power consumption varies based on equipment within the rack and its load, each rack should be equipped with a PDU—two for dual bus environments—capable of monitoring power consumption to the rack PDU, as well as overload-protected receptacle groups and, where required, at the receptacle level.


These systems can provide PDU, branch-level, and receptacle-level monitoring of voltage, kW, current, and kWh, giving the most direct measurement of power consumption and supporting higher data center efficiency and availability.



Monitoring Rack Conditions


With increasing densities, a single rack can now support the same computing capacity that used to require an entire room. Visibility into conditions in racks can help prevent many of the most common threats to rack-based equipment, such as accidental or malicious tampering.

If specified and installed correctly, rack monitoring units can be configured to trigger alarms when rack doors are opened, water or smoke is detected, or temperature or humidity thresholds are exceeded. Many units are equipped with cameras to capture video of the event. These “eyes inside the rack” can be connected to central monitoring systems where environmental data can be integrated with power data from rack PDUs, while providing local notification by activating a beacon or other alarm if problems are detected.



Monitoring Energy Efficiency


Automating collection and analysis of data from power systems can help reduce energy consumption while increasing IT productivity. Energy efficiency monitoring can track total data center consumption, automatically calculate and analyze PUE, and optimize the use of alternative energy sources.

Using real-time data from the many support systems, the monitoring system can track and trend total infrastructure power use and compare this to capacities. For example, for UPS power output, determine when UPS units are running at peak efficiency, and report Level 1 (basic) PUE. Monitoring at the room or row PDU provides the ability to more efficiently load power supplies, dynamically manage cooling, and automatically calculate Level 2 (intermediate) PUE. Panel board monitoring provides visibility into power consumption by non-IT systems, including lighting and generators, to ensure efficient use of those systems.






Finally, rack-level monitoring provides the most accurate picture of IT equipment power consumption and can support Level 3 (advanced) PUE reporting. The ability to automate data collection, and consolidate and analyze data related to efficiency—which is one of the primary jobs of the DCIM tool—is essential to data center optimization. These functions free up data center staff to focus on strategic IT issues.



Monitoring Batteries


Batteries have long been known as a weak link in the power chain. To prevent data loss and increase uptime, most data centers specify and require a dedicated battery monitoring system, which should be installed when the data center goes online. Using a predictive battery monitoring method can provide early notification of potential battery failure. The best practice is to implement a monitoring system that connects to and tracks the health of each battery within a string.

The most effective systems continuously track all battery parameters, including internal resistance, using a dc test current to ensure measurement accuracy and repeatability. Supported by a well-defined process for preventive maintenance and replacement, monitoring batteries can significantly reduce the risk of dropped loads due to battery failure, optimize battery life, and improve safety. The use of a battery monitoring system has an excellent payback period but, more importantly, provides peace of mind to the data center operator that the power system will react and support a load during a power outage.




INTELLIGENT CONTROLS


Previous generations of infrastructure systems were unable to adjust to dynamic load variations. UPS systems, meanwhile, operated most efficiently at full load, but full-load operation is the exception rather than the norm. The lack of flexibility in power systems led to inherent energy inefficiency.

Integrating intelligent control capabilities into data center power systems can help minimize the amount of energy being lost by enabling data center managers to tailor the performance of the UPS system to the specific efficiency and availability requirements of the site. When proper application of these capabilities is followed, it can enable double-conversion on-line UPS systems to operate at efficiency levels up to 97% while the inverter remains in operation.

Advanced UPS systems can employ an energy optimization mode that powers the load in reverse-transfer mode while keeping the UPS inverter at the ready to pick up the load in the event of a utility disturbance. An even higher degree of energy optimization provides power conditioning as well. The result is increased efficiency without compromising availability.

It is important that data center managers do not compromise on distribution and server power supply performance. Attention to distribution transformer and server power supply efficiencies can also reap huge benefits in improving PUE. Deploying TP1-rated distribution transformers can improve partial load efficiency by as much as 0.5%. High-efficiency server power supplies, while initially more expensive, can pay for themselves over their useful life.

About the Blogger


Strategic Media Asia Ltd (SMA) is one of the Approved CPD Course Providers of the Chartered Institution of Building Services Engineers (CIBSE). SMA exists to provide an interactive environment and opportunities for members of IDC industry and engineers to exchange professional views and experience on data center design, critical infrastructure system, electrical and mechanical facilities, etc.

SMA connects IT, Facilities and Design. For details, please visit our website at http://www.stmedia-asia.com/trainings.html.

4 Ways to Extend the Life of UPS Batteries

Data center backup power is a crucial element to uptime and availability. During an outage, Uninterrupted Power Supply (UPS) enables the switch from utility power to backup generator power. But there is a relatively unreliable and expensive variable to most UPS: batteries.

Batteries represent three evils: They are big, they are expensive, and they are expendable. Anything you can do to prolong the life of your batteries will indeed extend the availability of your data center.

So here are four ways that data center facility managers can extend the life of their UPS batteries.


(1) Buy the right UPS battery for your data center


In a data center, UPS is designed to fully discharge the battery source within 20 minutes. This is called high-rate discharge. High-rate batteries have thinner plates and more plates than lower-rate batteries, but as a result high-rate batteries can lead to a shorter lifespan.

There are many other factors in buying UPS batteries, such as the life expectancy, voltage, front or top access, flag post or inserted post, and other considerations. For example, a small format valve regulated lead acid (VRLA) battery has a relatively low first cost but lower reliability. Meanwhile, a nickel cadmium (NiCd) battery has the best reliability and longest service life, but the first cost can be four times as much as other batteries.

Data center manager must also be aware of potential manufacturing problems such as faulty post seal design and internal connection problems.


(2) Install, operate and maintain batteries correctly


Incorrect installation can lead to shortened battery life, as can improper maintenance. Good maintenance means giving the batteries well ventilated air that is as close as possible to 77 degrees Fahrenheit, and making sure that all batteries in the string are getting air within 3 degrees Fahrenheit to ensure that some of the batteries don't age more quickly than others.

Why? Mixing batteries of different ages or internal resistances can prompt batteries to die more quickly. Regular inspections of the batteries can unveil problems such as loose intercell connections and damaged post seals, which can lead to corrosion and even fires.

Data center manager should also be aware of the battery's discharge status as well. A fully or nearly fully discharged battery that isn't recharged within 48 hours can lead to damage. Overdischarging a battery can cause recharge problems, and excessive discharging -- for example, if a data center does weekly testing of its backup systems that includes battery cycling -- can reduce battery life.


(3) Monitor the UPS batteries' capacity


When the internal resistance of a battery rises due to normal aging factors such as corrosion, and when it has increased by as little as 30%, it's time to replace them. This is most often measured through capacity testing, as most manufacturers say that when a battery drops to 80% of its original capacity, it's cooked!

Users should perform capacity testing on their batteries based on IEEE standards; in particular, IEEE 1188 or IEEE 450.


(4) Flywheel UPS in conjunction with battery UPS


When flywheel UPS is installed with battery UPS, the flywheels can often handle the shorter power outages that happen more often and can prevent the batteries from cycling. The flywheel UPS also helps to extend battery life by two years preliminary.

In addition, flywheel can filter out the 'dirty power, such as little power blips and spikes. The batteries would filter those spikes out but if you hit the batteries with those spikes, it will kill the battery life.



About Strategic Media Asia Limited


Strategic Media Asia (SMA, www.stmedia-asia.com) is a professional training program and seminar organizer for corporations specialized in data center design & build, mission critical facilities, telecommunications infrastructure, financial IT and colocation services. Currently, SMA delivers a series of critical infrastructure training courses and qualification programs in Hong Kong and Macau.


For details, please visit www.stmedia-asia.com/trainings.html.

Data Center Power & Cooling Strategies

In today’s world of high-density data center equipment, power and cooling needs are a supply and demand problem. You should understand the supply limitations of a data center and the demand of the equipment. The cost of data centers is on the rise as a result of the increased power capacity required. While server costs have remained virtually consistent, power density has been increasing.

It’s imperative for CFOs to understand the cost of energy relative to the cost of the server because the need for more data centers is increasing due to the demand for more business applications.

Powering and cooling your own data center is not only of budgetary concern, there is risk in the continuity of the physical environment itself. It is recommended that the temperature ranges 16-24*C with a humidity of 40-55%. The temperature is constantly on the rise because the electrical power used heats the air.

Unless that heat is removed, the ambient temperature will rise, resulting in equipment malfunction. Too much humidity will cause water to condense on internal parts and not enough humidity can produce static electricity discharge problems which will damage components.







When housing your own center, it is critical that all elements of the electrical system, including backups, should be fully duplicated and critical servers connected to both the ‘A’ and ‘B’ power feeds. Your backup power should consist of one or more uninterrupted power supplies (UPS), battery banks, or diesel generators. Static switches are sometimes used to ensure instantaneous switch-over in the event of a power failure. Power is the critical element in a data center because its performance affects the proper execution of every other system in the facility.

If you choose to house your IT operations in data centers, computer rooms, NOC’s, or server farms, be diligent in your research of power and cooling systems because they need to be carefully coordinated. Your equipment and data need 24 hours of protection 7 days a week.


About The Blogger


Strategic Media Asia (SMA, www.stmedia-asia.com) is a leading technical training and event organizer for corporations specialized in data center design & build, E&M facilities, telecom, ICT, finance and colocation services. Currently, SMA delivers a series of data center trainings and qualification programs in Hong Kong, Taiwan and Macau.

All these events / training seminars are designed to support the leadership needs of senior executives (Chief Information Officers, IT Directors / Managers, Facilities Managers, company decision makers, etc.) and to provide useful and applicable knowledge.

For detail, please visit SMA's Technical Training Seminars & Data Center Qualification Programs.