There are several cabinet heights according to the needs of the installation, this height can be measured in rack units (U).

Each rack unit or U is the distance between each horizontal separation to place the different accessories inside the rack. This distance is 1.75 inches that is equal to 4.4445 cm high.

For example, if we say that a rack is 8U we will understand that it has 8 units to install device orAccessories of 4.44 cm in height.

Normally these accessories, like trays, guides, strips, etc. Occupy a unit of U (1U), but we can find that other devices or accessories occupy more units, for example can be a rack box to install a PC, a UPS, etc. It can be said that there is also a half unit of U (0.5U), in this case, two units could be installed in a rack unit.

As far as I knowEndo the units of rack that occupy the devices that we are going to install we will know the height that we need for our rack.

The size of the rack unit (U) is based on the standard specification for racks defined in EIA-310.

The RS232 connector is a connector type 9-pin connector is popularly called Series. It is a connector that was once widely used by various components of the PC, such as a mouse, keyboard ... but over time it has fallen into disuse and replaced by the USB connector trying to emulate the latest version number. It is currently used by robots, elevators, POS and industrial machinery.

The Simple Network Management Protocol, or SNMP (English Simple Network Management Protocol) is a protocol for the application layer that facilitates the exchange of management information between network devices. It allows administrators to monitor network performance, find and solve problems, and plan for growth. In an attempt to explain in a simple way, we could imagine that instala card using SNMP to monitor a UPS on a network.

An uninterruptible power supply, UPS, also known as UPS (uninterruptible power supply English), is a device that, thanks to batteries or other energy storage elements, can provide power for a limited time and for a blackout all the devices connected. Other features that can be added to these teams is to improve the power qualityéctrica reaching loads, ups and downs filtering and eliminating voltage harmonics of the network in the case of using AC. There are different types of UPS UPS DC loads connected to the UPS require DC power, so they will transform the alternating current to direct current sales network and use it to power the load and store it in your batterys. So they do not require converters between the batteries and loads. UPS AC UPS obtained These outputs an AC signal, so they need an inverter to convert the direct signal from the batteries in an alternating signal. UPS standby (Standby Power Systems) This system has two main circuits: the power line, which only addsa stabilized and additional filtering of each team to normal feed, and the actual circuit UPS circuit whose core is called "inverter". It is called system "standby" or waiting, because the circuit of alternative power, the inverter is "offline" or inactive, waiting to become operational when it produces a failure in the power supply. It has a switching element that connectsand either circuit switched alternately. UPS line-interactive (in-line) This type of UPS regulates voltage variations by elevations or reductions in mains voltage. During these interventions, the UPS uses its battery to perform the voltage regulation. UPS online (online) In contrast, the UPS "online" (on-line), the battery and the inverter are permanently It is utiized, ensuring a maximum response in a timely manner before the event of network failure. In addition, they can also correct the frequency shifts as re-generate the ac wave permanently. Diagram UPS online In the picture (1) Rectifier The picture (2): battery in the picture (3): Inverter

RS-232 (Recommended Standard 232, also known as EIA/TIA RS-232C) is an interface that designates a standard for the exchange of a series of binary data between a DTE (Data Terminal Equipment) and DCE (Data Communication Equipment , Data Communication Equipment), although there are others in which the RS-232 interface is also used. An equivalent definition published by the ITU is called V.24. The RS-232 is a connectorDB-25 type (25-pin), although it is normal to find the version of 9-pin (DE-9, or popularly also called DB-9), cheaper and even extended to certain types of peripherals (such as serial mouse PC).

One hertz is one cycle per second, meaning repeating cycle as an event. For example, hertz is applied physics measuring the number of times for a second wave (either acoustic or electromagnetic) is repeated or can be applied, among other uses, to ocean waves that reach the Beach vibrations per second or a solid. The quantity that measures the frequency hertz is called,in this regard, the inverse of the period. One hertz is an oscillation frequency of suffering a particle over a period of one second.

A rack is a metal support designed to house electronic, computer and communications equipment. The measures for the width are normalized to be compatible with most equipment manufacturers. They are also called racks, cabinets, cabinets or closets. Each column has holes at regular intervals called U rack units (Pictured: 4) grouped in threes. The height (Pictured:5) of the racks is standardized and external dimensions of 200 mm by 200 mm. Being normal that from 4U to 46/47U height width types (Pictured: 7). Standard 600 mm or 800 mm Types of background (Pictured: 6) The depth of the frame is not standardized, as this flexibility is granted (Pictured: 8) to the equipment. The most common are: - 450 mm - 600 mm - 800 mm - 900 mm - 1000 mm - 1200 mm Type 19-inch rack can find various types of 19-inch rack. Rack Mural (Pictured: 2): Used to accommodate electronic network. They are the smallest and are anchored to wall. Rack Pie (Pictured: 1): They are used primarily for servers, UPS and network electronics. Open Rack (Pictured: 3): Open Rack Racks are available only modelsstructure, eliminating doors and other accessories.