AC/DC power supply / DIN rail / redundant / Power-over-Ethernet
Contemporary Control Systems
DIN rail, redundant, Power-over-Ethernet
The EIPE PoE Power Injector in the Skorpion family offers a simple method of connecting a PoE end-device to a non-PoE 10/100 Mbps Ethernet switch. The EIPE is compliant to the IEEE 802.3af standard and is considered a mid-span PSE in that it resides between the non-PoE switch and the PD delivering the required 15.4 watts of power at its output connector. There are two RJ-45 connectors on the unit. The top connector, labeled IN, attaches to the non-PoE switch while the bottom connector, labeled OUT, attaches to the PD. Transmit and receive signals are freely passed between the two connectors as if the injector were not present. However, 48 VDC power is injected into the spare pins on the bottom RJ-45 connector for use by the PD. The injector does not interfere with any communication between the non-PoE switch and the PD.
The Power Injector supports the 802.3af protocol for powering up devices. With the Power Injector powered up, an Ethernet cable is attached to the PD. No power is applied to the PD until a valid 25 kΩ resistance, called the signature, is sensed by the Power Injector. Once this value is sensed, the Power Injector applies power to the unused pairs thereby powering the PD. Depending upon cable length, the PD can assume that a minimum of 12.95 watts is available at its input pins.
Like all other Skorpion products, the Power Injector is powered from a 24 VAC/VDC source using a 4-pin removable connector. Provisions exist for redundant power sources. The internal isolated power supply develops the required 48 VDC PoE power eliminating any concerns regarding grounded primary power.