This surge protection device (SPD) provides 6kV/3kA surge protection for a DC power source + balanced pair telecom-like signal, for example CAN-bus or RS485. This SPD is based on TVS diodes for the DC- rail protection. This eliminates the aging aspect of metal-oxide varistors. The gas-discharge tube on the differential pair still undergoes some wear from exposures, but since the typical expected exposure are only 1.2/50µs surges (due to coupling with the DC power lines), actual energy is much less than the 10/700µs surges that the part is rated for.
Standard versions are bare PCB modules, suitable for mounting in a dedicated enclosure (approximately 8×8cm junction box) or to be fitted somewhere in an existing enclosure. There are also clamps for DIN rail mounting.
- Versions for 12VDC and for 24VDC
- Series resistance 0.5Ω, maximum current 3A
- Maximum let-through voltage during 6kV/3kA surge at 85°C VNOM + 33%, so 16V and 32V respectively
- 6-Pin 3.81mm pluggable screw terminals for CAN-bus, ground, power, shield and earth
- Grounds and shields individually terminated to earth via 1nF Y1 capacitors
- 6kV Surge rated; 1.2/50µs 2Ω on DC-input, 12Ω to earth, 10/700µs 25Ω on CAN-bus/balanced pair
- Voltage to earth clamped with 1kVDC/6.5kA varistor
- 120Ω current-limited switchable termination
- Conformally coated circuit board 66mm × 60mm, 4mm oblong mounting holes pitch 56-60mm
- Available with various enclosures; antistatic glass-reinforced polyester (GRP) 80×75×55mm, polycarbonate, ABS or aluminium. Enclosed models delivered without cable glands
- ATEX increased safety 'ec' (IEC 60079-7), dust ignition protection 'tc' (IEC 60079-31)
- Customisable with industrial (M12) connections or cable assemblies