What does a UPS do ?
The distribution of electrical power is often subject to short and long term interference. Using an instantaneous back-up power supply means you can protect your IT system against such interference which can come from the industrial and atmospheric environment, as well as from your own environment. The following table lists the most common sorts of power supply problems, and the consequences for badly protected users: CAUSES CONSEQUENCES Voltage reduction Due to high voltage consumption required when starting up heavy equipment (motors, escalators, compressors, etc). Keyboard lock, system breakdown leading to data distortion or loss, reduction in equipment performance and lifespan. Excess voltage Lightning hitting power cables or the sudden shutdown of high-consumption equipment can cause temporary voltage increase. Breakdowns, electronic component wear-and-tear, destruction of hard disks. Cut-offs and micro cut-offs There can be many factors: lightning, live-line working, or heavy demand on the electrical network, etc. Data-loss, badly shut-off applications, equipment damage and problems when re-activating applications. Stray There can be many factors: atmospheric conditions, load permutations, generators, radio-emitters, household and industrial equipment. Program and database errors. Shock waves These are generally caused by lightning or when the mains supply is re-established after having been absent during a storm or following a motoring accident. Badly damaged components and equipment, data-loss..
The distribution of electrical power is often subject to short and long term interference. Using an instantaneous back-up power supply means you can protect your IT system against such interference which can come from the industrial and atmospheric environment, as well as from your own environment. The following table lists the most common sorts of power supply problems, and the consequences for badly protected users:
What are criteria for choosing a UPS ?
The answer to this question depends on the type of equipment you wish to protect. YOUR EQUIPEMENT CRITERIA INDIVIDUAL STATION Back-up The UPS should have enough back up to correctly shutdown the PC. Implementation We favour easy implementation (Plug & Play Windows) and ease of integration of the UPS in the office. LOCAL SERVER Quality of power supply Certain IT equipment (top-of-the-range workstations, for example) requires good quality current when the UPS is running on battery. We favour a UPS which produces a sine wave out-put signal. Voltage control The UPS must be able to control voltage should the variations be too high. Communication software Should the IT system be running on a network, it will be necessary to use software which enables the UPS to be controlled via the network. CRITICAL APPLICATION SERVER Perfect quality The availability of a critical server is fundamental to your company. As for a local server, great care must be taken over the quality of the current supplied by the UPS. Extending back-up time You could need longer back-up time, therefore it's important to easily add supplementary batteries to your UPS. No interruptions The UPS should supply high quality power without any interruption. To guarantee this you should choose a UPS which permanently controls voltage and frequency. Changing over to battery operation should be completely seamless, i.e. without any cut-off.
The answer to this question depends on the type of equipment you wish to protect.
Quality of power supply Certain IT equipment (top-of-the-range workstations, for example) requires good quality current when the UPS is running on battery. We favour a UPS which produces a sine wave out-put signal. Voltage control The UPS must be able to control voltage should the variations be too high.
Communication software Should the IT system be running on a network, it will be necessary to use software which enables the UPS to be controlled via the network.
Perfect quality The availability of a critical server is fundamental to your company. As for a local server, great care must be taken over the quality of the current supplied by the UPS.
Extending back-up time You could need longer back-up time, therefore it's important to easily add supplementary batteries to your UPS. No interruptions The UPS should supply high quality power without any interruption. To guarantee this you should choose a UPS which permanently controls voltage and frequency. Changing over to battery operation should be completely seamless, i.e. without any cut-off.
What are the differences between On-line, Off-line or Line-interactive technologies ?
OFF-LINE LINE INTERACTIVE ON-LINE Applications Low power Service industry with infrequent interference Recommended for <2kVA power ranges Service industry with infrequent interference Medium and high power UPS Service industry and industrial Battery transfer time during mains cut-off YES YES NO Frequency control NO NO YES Voltage control YES YES NO Voltage peak absorption NO SOME ALL Normal operational supply Mains Mains UPS Power supply during mains cut-off Battery with <10ms changeover Battery with <4ms changeover Battery without any interruption
Medium and high power UPS
Service industry and industrial
Is it necessary to protect a printer with a UPS ?
No, unless it's an industrial-style printer.
Is it necessary to protect a fax machine with a UPS ?
Yes and no. It’s not necessary to protect the fax machine itself, but the modem line needs to be protected against excess voltage, which could damage the device.
Are there any norms or standards concerning the choice of a UPS ?
There are numerous national (NF) and international (IEC) standards for UPS, but those standards covering safety (NF …), electromagnetic compatibility (IEC …) and quality (ISO) are all given priority. SOCOMEC SICON UPS satisfy all these standards and are also ISO 9001 certified.
Do I need a communication software ?
The UPS supplies power back-up in cases of electrical network failure. However, this back-up may not be enough to cover longer cut-offs and you may not be there yourself to correctly close-down your files and your IT system. UNI VISION communication software is designed to automatically carry out all the necessary operations to closedown your system before the end of battery back up. UNI VISION also offers remote communication with your UPS systems: • Status monitoring • Control programming • Statistics print-out for the quality of supplied power • Remote warning via fax, Email, MS-Exchange or pager.
Do I need a UPS in addition to a gen-set ?
Yes, for 3 reasons: • A gen-set supplies current with a high risk of frequency variation. A UPS able to provide perfect quality current is therefore an indissociable complement to a gen-set. • Supplied equipment may not be able to withstand motor start-up time (about 8-10 seconds). • The gen-set might not in fact start-up at all. The UPS will, however, ensure supply back up.
Is there a maximum ambient temperature for the correct operation of a UPS ?
The ideal ambient operating temperature for a UPS is 20°C. Nevertheless, the UPS and its components can operate satisfactorily within a range of 0°-35°C, excluding the battery. Using sealed lead-acid batteries requires a maximum local temperature of 25°C in order to maintain optimum reliability.
Are there any distance isolation processes ?
The notion of isolation is an approach to safety that is different, and even stricter than the emergency stop function. Generally speaking, isolation is linked to a notion of direct and unambiguous validation on the part of the operator concerning the action that he has just carried out. (checking to be certain that the breaking device is actually open, placing of padlocks, locks,...). This type of validation cannot be achieved by means of any electrical or electronic control system, however sophisticated it is. This requirement to make the equipment safe, if the general control is some distance away, may be fulfilled by complementary local safety breaking devices installed immediately next to the equipment that has to be kept shut down (safety breaking enclosure). Obligatory isolation measures are defined at European level in the machine directive of 29 07 92. The "installation" standards IEC 364 , NF C15 100, or "machine" standard IEC 60 204 complete these requirements for general isolation breaking, or for mechanical maintenance. As well as the fully visible breaking (devices suitable for isolation) and on-load breaking in accordance with IEC 60 947-3 required by the "installation" or "machine" standards above, certain health and safety committees or national representative institutions (e.g.: Work Inspectorate, regional health bodies, ...) may impose stricter requirements according to the site or the equipment concerned including notions of visible breaking or notions of the effective proximity of the breaking device to the machine.
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