Ethernet switches incorporate power supply

Paul Boughton
For users of modern, Ethernet-enabled video surveillance cameras, wireless access systems, Voip telephones and other edge-of-network devices, the ability to drive these products via Power over Ethernet (PoE) from a compact network switch can be a key advantage. But much of that benefit is lost if the Ethernet switch itself requires a separate power supply before it can be connected to the mains. Garrettcom Europe has addressed this issue with its IPS42 power supply chassis that is integrated within the PES42P hardened Ethernet edge switch.

With its integrated power supply, a single PES42P can power up to four PoE-enabled devices from a single AC outlet, as well as a high-speed fibre media uplink to the control centre. This gives users greater flexibility in deploying Ethernet-enabled devices, reducing system complexity and overall panel space requirements.

Compact, rugged and hardened for harsh industrial environments and outdoor use, the PES42P unmanaged edge switch provides a total of six Ethernet ports. Four ports are always RJ-45 for PoE, while the remaining two ports can be specified as two 100Mb fibre ports, or one fibre and one copper port, or two copper ports.

The PoE ports feature innovative auto-sensing technology so that they provide power only to attached 802.3af PD devices. If proprietary PoE or non-PoE devices are attached, the auto-sensing feature ensures they will not be damaged. The PES42P ports cease supplying power when the PoE devices are disconnected, and support the PSE (power sensing equipment) standard for over-current protection, under-current detection and fault protection.

A further feature of the PES42P switch is Link-Loss-Learn (LLL), which enables the device to be used in self-healing and redundant LAN structures. PES42P switches, combined with managed switches running STP or RSTP or S-Ring, can incorporate PoE devices and provide high-availability redundant LANs at lower total cost than was previously possible.

Garrettcom says the PES42P is suitable for use in a broad spread of industrial applications. It is NEBS L3 and ETSI compliant for vibration, shock and altitude, and carries UL, cUL and CE approvals. Emissions meet FCC Part 15, Class A standards. For use in power utility substations, the PES42P is certified to IEEE 1613 and IEC 61850 standards. The PES42P is rated for ambient temperatures from -40 to +75 degrees C, and is hardened for use outdoors and in challenging environments. On request, it can be supplied conformally coated for added protection against moisture, humidity and chemical attack.

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