This month we take a look at the Eaton 9140 Rackmount UPS which provides some of the best in class features to size and cost ratio on the market today.

If you are interested in a demonstration of the benefits of this product please call us on 0800 978 8988 to arrange your free demonstration.

The Eaton 9140 Rackmount UPS provides premium online backup power and scalable battery runtimes for medium- and high-density rack environments. Packing 10 kVA of power into only 6U, the 9140 UPS conserves valuable rack space. The 9140 significantly extends battery service life with ABM technology and prolongs runtimes with extended 3U battery modules.

Features and benefits, are as follows:

• Conserves valuable rack space with up to 10 kVA of power in only 6U of height, including batteries
• Significantly reduces installation time with pre-installed rackmount hardware
• Facilitates easy installation and reduces service time with modular, lightweight design
• Accommodates system growth with capacity upgrade availability from 7.5 to 10 kVA
• Increases battery service life and system uptime with ABM battery-charging technology and hot-swappable batteries
• Provides detailed information and UPS management in multiple languages via intuitive LCD interface

This double-conversion UPS resolves all nine common utility power problems and supplies clean, continuous power to all  connected equipment. If utility power goes out all together, there is no delay transferring to backup power, either to UPS batteries or an auxiliary generator.

Easily install and service your UPS The 9140 delivers high system availability—the key is an internal automatic bypass feature that allows the 9140 to continuously provide power to critical equipment while the system is serviced, even when the electronics are removed.

The 9140 also comes with user-replaceable battery and power modules. Both of these are easy for one person to switch out without disrupting power to protected equipment. If your computer room is dynamic and you find yourself frequently moving racks and other IT equipment, you may prefer a 9140
corded UPS, which is equipped with a standard IEC 309-60A cord with plug as input, which means you don’t need an electrician to install your UPS with each move.

Expanding UPS management capabilities

Getting even more protection for your network is easy to do. If you install a communication card in your 9140, you can easily integrate Eaton’s free Intelligent Power® Software Suite. This allows you to monitor and manage the power devices on your network from a single interface, giving you up-to-the-minute information on the status of power in your network. The Intelligent Power Software Suite:

• Provides critical information, such as UPS battery condition, load levels and battery runtime
• Seamlessly integrates with VMware® vCenter Server™ dashboard
• Triggers migration applications to move virtual machines during a power failure
• Gracefully shuts down computers and virtual machines/servers during an extended power outage
• Work with VMware, Microsoft®, Citrix® and Red Hat® virtualization platforms

To learn more, please just call us on 0800 978 8988

Overall Marks by Critical Power Supplies Ltd

Ease of installation 9 out of 10.

Design and build quality 9 out of 10.

Software functionality 10 out of 10.

Options and service plans 9 out of 10.

Overall - great product, feature rich at a great price.

To purchase this product from our web site please click here or just call us on 0800 978 8988

To download the product datasheet please click here

The very best power protection comes from a special type of transformer known as a Constant Voltage Transformer (CVT). Providing unparalleled reliability and conditioning performance, spikes and electrical noise are neutralised with attenuation as high as 75dB.

In addition the input and output transformer windings are physically separated. Known as Galvanic isolation this separation ensures that there is no direct connection between the mains supply and load. A CVT therefore provides an impenetrable barrier to spikes and high frequency electrical noise. This barrier also works in reverse mode to prevent a 'noisy' load from polluting the mains supply itself.

Click here to review the CVT product homepage

Superior sag surge and brownout protection:

Mains voltage sags and surges are automatically corrected by a CVT. When faced with an extreme surge voltage such as a local lightning strike the power conditioner will present a low impedance to the mains to protect both itself and any connected loads.

Automatic sine-wave generation:
using ferro resonant transformer technology means that each power conditioner will always generate a pure stable sine-wave even when fed from a polluted mains or square-wave supply.

Perfect switched-mode-power-supply (SMPS) driver:

Ferro resonant transformer technology provides waveform shoulder-lifting - the CVT is the kindest way to drive a switched mode power supply. Input surges are reduced prolonging life and conduction times are lengthened. In addition the CVT provides harmonic buffering and improved reservoir capacitor hold up for the inevitable supply micro breaks which occur with grid protection switching.

CVT how does it work?

AC stabilisation can be achieved using a simple magnetic device which has no moving parts. This is a process of producing a constant ac voltage from a varying ac voltage supply and involves the use of saturable reactors. The latter may be incorporated in a special transformer magnetic saturation being produced in a part of the magnetic circuit.

The winding arrangement and construction of one such constant voltage transformer is shown in the diagram:

The core is a three-limbed shell with a magnetic leakage path dividing the winding space. On the upper winding space is the primary and a
compensating winding while the lower winding space carries the secondary which has a capacitor connected across it. An increasing
voltage applied to the primary produces an increasing flux in the main magnetic circuit and the secondary voltage increases proportionally to
this voltage. The increasing flux produces an increase in the leakage reactance of the secondary and this approaches a value which resonates
with the capacitor connected across it. As the condition of resonance is reached the secondary current rises rapidly saturating the lower portions
of the magnetic circuit. The flux due to the primary is diverted through the magnetic shunt and further increases in primary voltage produces
little change in the secondary emf. It increases very slowly and this is offset by the emf induced in the compensating winding on the upper
portion of the core which is connected in series opposition to the secondary winding.

Thus once the secondary is brought to resonance the output voltage from the secondary and compensating windings is
constant and it is under these conditions that the transformer is used. The advantage of this form of stabilisation is that it can be applied to the heater supplies in addition to any HT supplies derived from it. Owing to the non-sinusoidal waveform however readings taken with the usual rectifier-type meters are subject to error.

The compensating winding produces a small voltage which is used to 'buck' the output voltage. To produce a sinusoidal waveform a further winding is added which is coupled via a magnetic gap. This extra 'neutralising' winding can be arranged to provide a suitable amount of 3rd and 5th harmonics which when summed with the output 'square' wave above results in a sinewave.

Click here to review the CVT product homepage

Eaton has just announed new connectivity cards for their UPS solutions will be shipping from February 2012.

Network Card-MS
The new Network Card-MS (Network-MS) replaces Eaton’s previous ConnectUPS-MS card (103006826) and the Network Management Card (66102). The Network Card–MS Web/SNMP Card allows an Eaton UPS to directly connect to Ethernet networks and the Internet, supporting real-time monitoring and control of UPSs across the network via a standard Web browser, SNMP-compliant network management system or power management software.

Features include:
- Versatile support through HTTP, SNMP, SMTP, Telnet, SSL and SSH compatibility
- Remote management of a UPS or rebooting of protected devices over SNMP/Web
- Customizable actions including automatic shutdown in the event of an extended power failure
- Email notification of alerts
- Compatible with SNMPv3 and IPv6

Network and MODBUS Card-MS
The new Network and MODBUS Card-MS (MODBUS-MS) replaces the former iNMC (industrial Network Management Card 66103). This option provides all of the features listed above in the Network Card-MS as well as continuous, reliable and accurate remote monitoring of a UPS system through a Building Management System (BMS) or Industrial Automation System (IAS). Enabling data to be integrated from the UPS into a wide variety of management systems, the Network and MODBUS Card-MS combines an SNMP agent, HTTP/Web server and a MODBUS card, facilitating UPS supervision from any network monitoring system using SNMP and traps, or any web browser.
New functionality: supports 9130 UPS

Relay Card-MS
The new Relay Card-MS (Relay-MS) replaces Relay Management Card Contacts & RS232 –MS (103006828) and Relay Management Card (66104). The card provides a simple way to remotely deliver UPS information to an alarm system, PLC or computer system via dry contacts (relay), or it can be an RS232 interface for connection to a PC.

Please see the table below for confirmation of old and new part numbers.

Our e-store and web pages will be updated over the next 5working days, however  if you have any queries please contact us on 0845 519 3638 or email support@criticalpowersupplies.co.uk

Note: National roll out projects will not be affected by this product update.

Yours sincerely.

Support @ Critical Power Supplies.

Selecting a battery or system of batteries that will provide your Inverter/Charger with proper DC voltage and an adequate amp-hour capacity to power your application is straight forward. Even though Tripp Lite Inverter/Chargers are highly-efficient at DC-to-AC inversion, their rated output capacities are limited by the total amp-hour capacity of connected batteries and the support of your vehicle’s alternator if the engine is kept running.

• STEP 1: Determine Total Wattage Required
Add the wattage ratings of all equipment you will connect to your Inverter/Charger. Wattage ratings are usually listed in equipment manuals or on nameplates. If your equipment is rated in amps, multiply that number times AC utility voltage to determine watts. (Example: a ¼ in. drill requires 2½ amps. 2½ amps × 120 volts = 300 watts .)

Note: Your Inverter/Charger will operate at higher efficiencies at about 75% - 80% of nameplate rating.

• STEP 2: Determine DC Battery Amps Required
Divide the total wattage required (from step 1, above) by the battery voltage (12) to determine the DC amps required.

540 watts ÷ 12V = 45 DC Amps

• STEP 3: Estimate Battery Amp-Hours Required (for operation unsupported by the alternator)
Multiply the DC amps required (from step 2, above) by the number of hours you estimate you will operate your equipment exclusively from battery power before you have to recharge your batteries with utility- or generator-supplied AC power. Compensate for inefficiency by multiplying this number by 1.2. This will give you a rough estimate of how many amp-hours of battery power (from one or several batteries) you should connect to your Inverter/Charger.

45 DC Amps × 5 Hrs. Runtime
× 1.2 Inefficiency Rating = 270 Amp-Hours

NOTE! Battery amp-hour ratings are usually given for a 20-hour discharge rate. Actual amp-hour capacities are less when batteries are discharged at faster rates. For example, batteries discharged in 55 minutes provide only 50% of their listed amp-hour ratings, while batteries discharged in 9 minutes provide as little as 30% of their amp-hour ratings.

• STEP 4: Estimate Battery Recharge Required, Given Your Application
You must allow your batteries to recharge long enough to replace the charge lost during inverter operation or else you will eventually run down your batteries. To estimate the minimum amount of time you need to recharge your batteries given your application, divide your required battery amp-hours (from step 3, above) by your Inverter/Charger’s rated charging amps.

270 Amp-Hours ÷ 55 Amps
Inverter/Charger Rating = 5 Hours Recharge

NOTE! For Tripp Lite Inverter/Chargers providing 1250 watts or less of continuous AC power, a full-size battery will normally allow sufficient power for many applications before recharging is necessary. For mobile applications, if a single battery is continuously fed by an alternator at high idle or faster, then recharging from utility or generator power may not be necessary. For Tripp Lite Inverter/Chargers over 1250 watts used in mobile applications, Tripp Lite recommends you use at least two batteries, if possible fed by a heavy-duty alternator anytime the vehicle is running. Tripp Lite Inverter/Chargers will provide adequate power for ordinary usage within limited times without the assistance of utility or generator power. However, when operating extremely heavy electrical loads at their peak in the absence of utility power, you may wish to “assist your batteries” by running an auxiliary generator or vehicle engine, and doing so at faster than normal idling.

If you need additional information or assistance with sizing your battery please call us on 0845 519 3638 or contact us via e-mail.

• How do you reliably power single power source switches in Rack?
• I need an STS I can control over the network but who makes one?
• I need a 1U 16amp STS, but having trouble finding one?
• I need an extended warranty on my STS, but can't get three years or more, who provides one?

Well Critical Power Supplies has the answers in the form of the Eaton 16amp STS and the Riello MultiSwitch MNS

Click here to read more >

Product Focus "Secure-Tec Surge Protection 15.000 A" With acoustic warning when surge protection fails.

Purchase online at Critical Power Supplies Ltd E-Store

Features and Benefits.

1. NEVER EVER rely on a single VRLA battery string. Always deploy at least Two VRLA battery strings in parallel to provide whatever your specified capacity requirement is.

2. Ensure the physical environment has proper ventilation, and temperature control.

3. Ensure the battery charger /rectifier is set to the correct float charge voltage and has a “clean” output.

4. Ensure that you initialize/install the battery system in accordance with the manufacturer’s requirements. Note that most VRLA batteries do not require initialization if they are put in before a specified time frame or if the open circuit voltage is above a specified level.

5. During installation, ensure you measure and verify the battery intercell connections are exactly where they should be.

6. Using a calibrated load, discharge capacity test the battery system within 30 to 120 days of installation.
The importance of these fundamental 6 items cannot be overstated. This provides the user a very high degree of confidence. The user now knows that one battery string will not take his service down. The user knows that nothing has been left to chance on the quality of the initialization and installation and all baseline measurements are valid. The user knows the true condition of his battery systems within 6 months of the installation. Accomplishing this greatly increases the probability for your battery systems to perform to their full expected service life duration.

7. Perform inspections, perform online Ohmic testing, float voltage measurements, float current measurements, temperature measurements, and offline discharge testing through maintenance and/or monitoring to the degree you can afford to do so. Do No Less Than: monthly inspections; annual online measurements; and offline discharge testing once every 3 years (or sooner).

We have just updated our information on Suitable Rooms for Stationary Batteries.

Summary -

For safety reasons, no smoking or naked flames should be permitted in rooms containing Standby Power battery installations. Batteries can be housed satisfactory in almost any reasonably well ventilated and illuminated room. As the life of a standby power battery is heavily dependent upon regular maintenance. This is much more likely to be done effectively if there is easy access to each cell and good lighting. Exposure to direct sunlight however is not recommended. 

Note: Should the above link not work please copy and paste the following URL into your web browser 

http://www.criticalpowersupplies.co.uk/news/Battery-Room-Considerations

We trust this information meets with your approval and you have received this information as a subscriber to our support news update service.

Yours sincerely.

Jason Koffler

jasonk@criticalpowersupplies.co.uk

Sales: 0845 519 3638

24x7 Support: 0845 519 3928

http://www.criticalpowersupplies.co.uk

http://support.criticalpowersupplies.co.uk

Critical Power Supplies has launched our brand new brochure, packed full of information on our products and services. Why not request your copy today or click here.

The brochure features useful information and images of how we can help your critical power and critical energy deliver power where and when its needed - efficiently.

All of the product information is available through our web site at www.criticalpowersupplies.co.uk or to be sent a copy please email sales@criticalpowersupplies.co.uk.

You have received this information as a registered support customer for Critical Power Supplies, to be removed from future news update please adjust your preferences in your support account or call marketing on 0845 519 3638.

Yours sincerely.

Jason Koffler

DDI: 0845 519 3638

E-mail: jason@criticalpowersupplies.co.uk

www.criticalpowersupplies.co.uk

Support.criticalpowersupplies.co.uk

Yours sincerely.

Jason Koffler

Sales: 0845 519 3638

Fax:0845 519 3639

www.criticlpowersupplies.co.uk

support.criticalpowersupplies.co.uk

How much battery do you need to run your device?

Here is how you estimate the size of battery you require for your load. 

Q = I*t

where Q is the charge in coulombs, I is the current in amps and t is the time in seconds.

The amount of charge passing through that wire (conducting 1.0 amps) in 60 seconds is 60 coulombs, and in one hour you would have had said “hello” and “good-bye” to 3600 coulombs of charge.

Batteries were evidently developed by engineers who subscribed to the “whatever’s easiest” system of measurement. They got tired of pulling out their slide rules to divide by 3600 every time they wanted to know how long 24000 coulombs would last them and came up with the unauthorized unit of amp-hours. Later, when smaller batteries were used they came up with milliamp-hours.

Don’t be confused by the hyphen. Amp-hours means amps times hours. Divide by amps and you get hours, divide by hours and you get amps. So it isn’t amps, and it isn’t amps per hour, it is amp-hours.

Amp hours is how much charge is stored in the battery. Since a battery changes voltage during the discharge, it isn’t a perfect measure of how much energy is stored, for this you would need watt-hours. Multiplying the average or nominal battery voltage times the battery capacity in amp-hours gives you an estimate of how many watt-hours the battery contains.

E = C*Vavg

Where E is the energy stored in watt-hours, C is the capacity in amp-hours, and Vavg is the average voltage during discharge. Yes, watt-hours is a measure of energy, just like kilowatt-hours. Multiply by 3600 and you get watt-seconds, which is also known as Joules.

As long as we are in the prelude, I might also mention that since the charge in a capacitor is Q=CV that a battery can be rated in farads as well. A 1.5 volt AA alkaline battery that stores 2 amp hours of charge (that’s 7200 coulombs) has the equivalent capacitance of 4800 Farads. Of course a battery makes an awfully weird capacitor because the voltage doesn’t drop proportionally to the stored charge, it has a high equivalent resistance, and etc.

The following method assumes that you know how many amps you need for the gadget under power. If you know the watts go to Step A below.

Step 1. Calculation

 If the current drawn is x amps, the time is T hours then the capacity C in amp-hours is

                        C = xT

For example, if your pump is drawing 120 mA and you want it to run for 24 hours

                        C = 0.12 Amps * 24 hours = 2.88 amp hours

Step 2. Cycle life considerations

It isn’t good to run a battery all the way down to zero during each charge cycle. For example, if you want to use a lead acid battery for many cycles you shouldn’t run it past 80% of its charge, leaving 20% left in the battery. This not only extends the number of cycles you get, but lets the battery degrade by 20% before you start getting less run time than the design calls for

             C’ = C/0.8

For the example above

            C’ = 2.88 AH / 0.8 = 3.6 AH

Step 3: Rate of discharge considerations

Some battery chemistries give much fewer amp hours if you discharge them fast. This is a big effect in alkaline, carbon zinc, zinc-air and lead acid batteries. It is a small effect in NiCad, Lithium Ion, Lithium Polymer, and NiMH batteries.

For lead acid batteries the rated capacity (i.e. the number of AH stamped on the side of the battery) is typically given for a 20 hour discharge rate. If you are discharging at a slow rate you will get the rated number of amp-hours out of them. However, at high discharge rates the capacity falls steeply. A rule of thumb is that for a 1 hour discharge rate (i.e. drawing 10 amps from a 10 amp hour battery, or 1C) you will only get half of the rated capacity (or 5 amp-hours from a 10 amp-hour battery). Charts that detail this effect for different discharge rate can be used for greater accuracy.

For example, if your portable guitar amplifier is drawing a steady 20 amps and you want it to last 1 hour you would start out with Step 1:

            C=20 amps * 1 hour = 20 AH

Then proceed to Step 2

            C’ = 20 AH / 0.8 = 25 AH

Then take the high rate into account

            C’‘=25 /.5 = 50 AH

Thus you would need a 50 amp hour sealed lead acid battery to run the amplifier for 1 hour at 20 amps average draw.

Step 4. Battery Sizing Calculation Technote.

What if you don’t have a constant load? The obvious thing to do is the thing to do. Figure out an average power drawn. Consider a repetitive cycle where each cycle is 1 hour. It consists of 20 amps for 1 second followed by 0.1 amps for the rest of the hour. The average current would be calculated as follows.

20*1/3600 + 0.1(3559)/3600 = 0.1044 amps average current.

(3600 is the number of seconds in an hour).

In other words, figure out how many amps is drawn on average and use steps 1 and 2. Step 3 is very difficult to predict in the case where you have small periods of high current. The news is good, a steady draw of 1C will lower the capacity much more than short 1C pulses followed by a rest period. So if the average current drawn is about a 20 hour rate, then you will get closer to the capacity predicted by a 20 hour rate, even though you are drawing it in high current pulses. Actual test data is hard to come by without doing the test yourself.

If you know the watts instead of amps, follow the following procedure

Step A: Convert watts to amps

Actually, watts is the fundamental unit of power and watt-hours is the energy stored. The key is to use the watts you know to calculate the amps at the battery voltage .

For example, say you want to run a 250 watt 110VAC light bulb from an inverter for 5 hours.

Watt-hours = watts * hours = 250 watts * 5 hours = 1250 watt hours

Account for the efficiency of the inverter, say 85%

Watt-hours = watts * hours / efficiency = 1250 / 0.85 = 1470 watt-hours

Since watts = amps * volts divide the watt hours by the voltage of the battery to get amp-hours of battery storage

Amp-hours (at 12 volts) = watt-hours / 12 volts = 1470 / 12 = 122.5 amp-hours.

If you are using a different voltage battery the amp-hours will change by dividing it by the battery voltage you are using.

Now go back to Steps 2-4 above to refine your calculation.

Please do not hesitate to contact us if you require any additional information on 0845 519 3638 or support@criticalpowersupplies.co.uk

All business continuity plans include some element of Critical Power protection. Generator and UPS maintenance including battery maintenance is a key element within such Critical Power plans to ensure performance is not comprised in an emergency. Maximum uptime is secured through regular maintenance visits to site, inspections and monitoring on a site or remote basis. At Critical Power Supplies our maintenance plans include:

• Health Checks: regular health checks to guarantee optimum performance including battery impedance checking to eliminate problems before they become a major fault.
• Flexible Configuration: maintenance plans configured to suit your installation, budget and response time needs.
• Guaranteed Response Times: within four clock hours, eight or twelve working hours responses.
• 24-7 Technical Support: round-the-clock technical support to help with alarm conditions and questions regarding operating status and system design.
• Fixed Price Plans: including associated emergency repair labour, parts and Preventative Maintenance (PM) visits.
• Multi Brand, Multi Vendor Support: with maintenance plans available for third party UPS systems and installations in the UK and Eire.
• Certified Engineers: factory trained engineers available on a nationwide basis providing support for our multi-brand and manufacturer policy.
• Spares Accessibility: strong supply chain management to ensure Critical Power Supplies can access the spares required to bring your system back on-line in the event of a system failure.
• 24-7 Remote Monitoring: site monitoring from dedicated service centre systems for immediate alarm resolution, diagnostics and despatch of a certified service engineer to site.
• SMS Alerts: SMS Text Alerts to upto 5 mobile phone numbers of your choice, Critical Power Supplies typically request that one of the numbers is our 24×7 service number so we can assist you immediately. Users can choose the type of alerts responded to.

Emergency Call Outs

Critical Power Supplies is a 24-7 business supporting critical installations across the UK and Eire. If you need to access our support team outside our normal working hours and do not have a maintenance plan in place, please dial 0845 519 3928 and we will provide immediate assistance.

Critical Power Supplies makes choosing a battery or replacement straight forward and we have created the following short battery guide based on the popular batteries from the leading manufacturers of batteries.

http://www.criticalpowersupplies.co.uk/choosing-a-battery