Howto:How to set IP200 Power over LAN Power Classification right

From innovaphone-wiki

Jump to: navigation, search

The IP200 has a power consumption of less than 4Watt and thus qualifies as class 1 (max. 3,84W) power over LAN devices. However, in contrast to IP110, IP200A and IP230 it does not announce its power class to the PoE switch.

Contents

Applies To

IP 200

More Information

Details

The IEEE 803.2af standards defines several classes for power over ethernet devices according to their power consumption, as shown below in Table 1.


IEEE 802.3af PSE and Powered-Device Power Classifications

IEEE Class Usage Minimum Power Output at the PSE Maximum Power Input at the Powered Device
0 Default 15.4W 0.44 to 12.95W
1 Optional 4.0W 0.44 to 3.84W
2 Optional 7.0W 3.84 to 6.49W
3 Optional 15.4W 6.49 to 12.95W
4 Reserved for future use Act as Class 0 Reserved for future use

Table 1. PoE classification

PoE devices shall negotiate its power with the providing switch. This allows the switch to make sure enough power can be supplied for all devices.

According to the IP 200 datasheet, its power consumption is 450mA at 12V. However, in practice, the device consumes less power, so it can be operated as a class 1 device.

Installation

Newer IP200(labeled as “IP200A” on the backside) and IP230/IP110 will properly negotiate their class with the switch. Such capable devices will do power classification negotiation automatically. No special configuration is required thus.

Older, yet power-over-ethernet capable IP200 models do not support class negotiation and will thus be considered “class 0” by the switch. This may result in a situation where a switch will refuse to power all of the IP200 connected to its power over ethernet ports. In such a case, we recommend to manually configure the ports used for the IP200 as “class 2” device. Most PoE switches available today will support all ports with PoE then.

Personal tools