Comparison Hikvision DS-7616NI-Q1(D) vs Hikvision DS-7616NI-Q2

The number of RCA analogue audio outputs provided in the design of the registrar.

This type of output is used primarily for audio output when viewing footage, in addition to the BNC and/or VGA output. Therefore, there are few such connectors in modern registrars — one, less often two (one each for BNC and VGA).

The maximum data transfer rate supported by the DVR's LAN ports.

Note that for simple tasks, a rather modest by modern standards speed of 100 Mbps is often enough. However, high bandwidth ( 1 Gbps) not only simplifies the transfer of large amounts of data, but also helps to reduce lags and improve the overall quality of communication; and modern technologies make it possible to provide support for gigabit LAN even in fairly simple and inexpensive registrars.

Of course, in order to use all the features of the LAN, it is necessary that the devices connected to such ports also support the appropriate speeds.

Standards (codecs) used by the recorder to compress the recorded video.

This parameter is important when viewing recorded materials on another device — for example, a media centre, into which a "flash drive" with files from the recorder is inserted. For normal viewing, it is necessary that the player supports the appropriate codec — otherwise the video will be displayed with distortion or will not work at all. Technical details on various standards can be found in special sources.

Note that if you plan to view the materials on a computer, you can not pay much attention to this parameter: most modern operating systems have extensive built-in sets of codecs, and if you don’t have the right codec, you can easily find it on the Internet.

The number of SATA connectors provided in the design of the registrar.

SATA is the most popular modern interface for connecting internal drives. One connector allows you to connect one hard drive (or other internal media), that is, the number of such connectors is, in fact, the largest number of separate drives that can be installed inside the recorder at the same time. Basic versions can be equipped with one SATA connector or two. More advanced ones have 4 SATA connectors, and already models for serious objects have much greater connectivity.

The largest total storage capacity with which the recorder is able to work correctly. By default, it is indicated only for internal media with a SATA interface (see above), however, in some models, data is also provided separately for external devices connected via eSATA.

Note that the limit on the total capacity follows from the fact that each individual port has its own limit on the capacity of the drive. In this case, the maximum capacity is distributed equally between the ports. This should be taken into account when choosing drives for the registrar: for example, in a 32 TB model with 8 SATA connectors, the limit for each connector will be 32/8 = 4 TB. This means that installing two internal 8 TB disks in such a registrar will not work, although their total capacity will be less than the maximum.

The range of ambient air temperatures at which the recorder is guaranteed to remain fully operational, and the likelihood of interference and failures is minimal. In most cases, recorders are installed indoors with a quite favorable microclimate, while the operating temperature range is quite extensive — for example, a value of -10 ... +55 °C is not unusual. Therefore, you should pay attention to this indicator only when installing in difficult conditions — for example, in an unheated warehouse or in a production room with elevated temperatures.

The highest relative air humidity at which the recorder is able to operate for an unlimited time without failures and breakdowns.

High air humidity has a negative effect on electronics: moisture can settle on various parts, including current-carrying, cause corrosion, short circuits, etc. This does not happen immediately, short-term work in high humidity may not cause any trouble, but a long stay in such conditions is not recommended. However, in most modern recorders, the permissible humidity is quite high — about 90%; indoors, such conditions are very rare.

Support of the registrar of the ONVIF standard.

This standard describes the protocols for the interaction of various components of a video surveillance system; a registrar that supports it will be fully compatible with other ONVIF equipment, regardless of manufacturer.

Recorder compatibility with CMS tools.

CMS is a set of software designed to manage the recorder from a PC. At the same time, the capabilities of this software include not only work with one device, but also the creation of a single video surveillance system from several registrars — so that control and data output from them is carried out through one computer. Anyway, the use of CMS can greatly simplify the work with the registrar.