Galvanic Isolator & Surge Protector HST-1F EXT (UTP balun)



Video Galvanic Isolator HSO-1F ECO (BNC)
View of the device (the ground has to be connected to the terminal in the middle)
HST-1F EXT is a balun matching the impedance of the unbalanced video input/output of a CCTV device with the impedance of balanced transmission line (UTP cable), combining very efficient surge/overvoltage protection and galvanic isolation of the connected device from the line. It provides immunity to lightning surges, ESD, ground loops. HST-1F EXT is specially dedicated for CCTV systems transmitting HD video signals (AHD, HD-CVI, HD-TVI), as well as can be used in CVBS systems.
It galvanically isolates two parts of the transmission path, such as the part with a camera and that with a DVR or monitor, protecting the devices against the effects of potential differences (image distortions caused by stray currents). The application of galvanic isolators is recommended in CCTV systems located in industrial environments, such as metal halls, on metal poles, and in the case of power supply from different segments of AC power network. In such circumstances some differences in potential appearing between individual grounding points introduce unfavorable operating conditions of the input/output circuitry. The differences and stray currents can generate disturbances visible in the picture and even damage the connected devices.
Maximum level of protective effectiveness is provided by galvanic isolation up to 800 VDC and 2 x 10 kA surge protection, containing a unique solution with ultra-fast MOSFET fuses. It ensures extreme immunity against voltage surges, atmospheric discharges and potential differences. The MOSFET fuses increase the effectiveness of surge protection and protect the transformer of the isolator from damage due to the flow of large impact current pulses.
The idea of the protection system
The bandwidth of the isolator has been adjusted accordingly to the requirements of analog HD transmission systems, allowing the transmission of video in resolutions up to 1080p. The device uses branded BNC connector, which ensures high quality and durability of the connection, even in adverse temperature conditions.
The device transmits the video signal in both directions and can be used on either side of the transmission line. However, in the case of longer transmission lines, the recommended location is by the DVR/monitor.
Galvanic Isolator & Surge Protector HST-1F EXT (UTP balun)
Application example

Code M17109
Input connector (line from a camera) Screw connection, removable
terminal block
Output connector (to a recording/monitoring device) Cable terminated with BNC-m
Bandwidth 42 MHz
Attenuation 0.6 dB
Overvoltage suppressors Gas discharge tube, Transil™, MOSFET fuses
Line to ground protection Gas discharge tube: 90 V, 2x10 kA @ 8/20 μS
Wire to wire protection Transient voltage suppressor: 6 V, 15 A @ 8/20 μS
Insulation breakdown voltage min. 800 VDC
Capacitance of the protection circuits 10 pF
Dimensions 82 mm x 24 mm x 31 mm (excluding the cable)


Model HST-1F EXT
Product type Surge arrester, Galvanic separator
Brand Ewimar
Input parameters number 1
connector type Removable screw socket
UTP impedance ohm 100
Operating band MHz 42
Output parameters number 1
connector type Cable with male BNC connector
BNC impedance ohm 75
Loss dB 0,6
Protection poziom izolacji VDC 800
surge protection Gas protector, transil, MOSFET fuse
line-to-ground protection Gas protector: 90 V, 2 × 10 kA @ 8/20 us
line-to-line protection Protective bridge: 6 V, 100 A @ 8/20 us
protection circuit capacitance 10 pF
Operating temperature °C -40 .. 60
Dimensions mm 82 × 24 × 31