SFD-C – COMBINED POWER & SIGNAL PROTECTORS
SFD-C – Combined Power and Signal Protectors
Novaris SFD1-C protectors are designed for for both power and signal protection in one compact and economical DIN compliant package. Ideal for security and CCTV camera protection.
Product Codes: SFD1-2-3-30-C, SFD1-6-3-30-C, SFD1-2-10-50-C, SFD1-6-10-50-C, SFD1-2-10-130-C, SFD1-6-10-130-C, SFD1-2-10-275-C, SFD1-6-10-275-C
The distributed nature of a CCTV network makes the system particularly susceptible to lightning and surge activity. During a surge event each remote camera and the DVR will rise to a different earth potential as each unit has a different impedance to ground. This can cause insulation breakdown and overcurrent problems for the equipment. To protect against these effects the protection device provides a low impedance path that reacts at a voltage lower than the insulation breakdown voltage of the equipment. This application note details the surge protection devices available for a most CCTV protocols and applications.
The distributed nature of a CCTV network makes the system particularly susceptible to lightning and surge activity. During a surge event each remote camera and the DVR will rise to a different earth
potential as each unit has a different impedance to ground. This can cause insulation breakdown and overcurrent problems for the equipment. To protect against these effects the protection device provides a
low impedance path that reacts at a voltage lower than the insulation breakdown voltage of the equipment.
It is important that protection is installed at both ends of a signal cable run. If only a single SPD is installed, the surge exposure will increase because of this lower voltage reaction.
This application note details the surge protection devices available for a most CCTV protocols and applications.
- By installing surge protection at both ends of the signal cable:
- The surge current has a clear path to ground at both ends
- The effective protection on the cable is doubled
- The shield wire can be used as a temporary equipotential bond during the surge
- The equipment at both ends is effectively protected due to their proximity to the SPD.
STANDARDS COMPLIANCE
- IEC 61643-11 class III
- AS/NZS 1768 categories A
- IEEE C62.41 categories A
- IEC 1000-4-5
- UL1449 fourth edition
- ITU-T K.44
- IEC 61643-21
- UL497B
- SFD1-x-10-275-C: This series is designed for 230 VAC systems and handles a 10 kA surge on the power line and a 20 kA surge on the signal line.
- SFD1-x-10-50-C: This series is designed for lower voltage 40 VAC systems and handles a 10 kA surge on the power line and a 20 kA surge on the signal line.
- SFD1-x-3-30-C: For lower voltage 24 VAC systems, this model provides 3kA of protection for the power line and 20kA for the signal line.
- Protection Details:
- Power Protection: Utilizes a 3-stage protection system with a low-pass LC filter, offering all-mode protection (L-N, L-PE, N-PE) and a low let-through voltage to safeguard sensitive equipment.
- Signal Protection: Features multistage protection using gas discharge tubes and fast transient suppression circuits, with options specifically for PoE over coax applications.
- CL Coaxial Protectors: These dedicated coaxial surge protectors (e.g., CLB12-90, CLB-68V) are suitable for various voltage and frequency requirements, including specialized 68V versions for PoE over coax.
- SFD Surge Filters: Available in various current ratings (2A-32A), these power line filters provide robust 3-stage protection for the mains input to DVRs and other control equipment.
- SL Signal Line Protectors: For PTZ camera control signals (e.g., RS485 protocol), the SL-485 range offers multi-stage protection for the twisted pair control wiring.