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1. Technical description
1.1. General description.
The SF108-B is dedicated for uninterruptible power supply of 8 IP cameras (52 V DC power supply).
The main elements of this system include:
- 10 ports PoE (SF108) switch
- 27,6V (PSB-1552455) buffer power supply with two 17 Ah / 12 V batteries
- a converter (DC/DC52230) increasing the voltage to 52 V DC (supply of the PoE switch).
In case of power decay, a battery back-up is activated immediately.
The approximate backup time is given assuming that all output ports are used (using typical devices and 17 Ah
batteries). The electricity consumption for own needs and the energy efficiency of the power intake track were taken into
account. The exact description of how to perform the calculations can be found at:
"Approximate backup time - assumptions
Automatic detection of any devices powered in the PoE/PoE+ standard is enabled at the 1
– 8 ports of the switch. The
G1/TP and G2/TP ports is used for connection of another network device via RJ45 connector. The switch is fitted with SFP
two slots; the use of fiber optic module (GBIC) allows fiber optic transmission. The LEDs at the front panel indicate the
operation status (description in the table. 8).
The switch is housed in a metal enclosure (color RAL 9003) which can accommodate a two 17 Ah/12 V batteries. The
enclosure features a micro switch tamper indicating door opening (front panel).
The SF108-B is fitted with two LEDs on the front panel (red LED
– indicates 230 V power supply of the PSU, green LED
indicates the presence of DC voltage).
The PoE technology ensures a network connection and reduces installation costs by eliminating the need to supply a
separate power cable for each device. This method allows supplying other network devices, such as IP phone, wireless
access point or router.
1.2 Block diagram.
Fig. 1. Block diagram.
