Building management system with ethernet cabling for building devices

1 . A method, the method comprising:

determining, using a first building device, a protocol for communicating with a plurality of second building devices in a building system of a building, the second building devices coupled by an Ethernet cable, wherein at least one of the second building devices is coupled to the first building device;

selecting a transceiver from a plurality of transceivers of the first building device based upon the protocol, the plurality of transceivers each being configured for a respective protocol;

communicating with the at least one of the second building devices using the transceiver and the protocol;

determining an end of line status for the first building device; and

engaging an end of line circuit in response to the end of line status.

2 . The method of claim 1 , further comprising:

determining the end of line status for the first device by measuring impedance, providing polling signals, or receiving a microswitch signal.

3 . The method of claim 1 , wherein the Ethernet cable is coupled to at least one of a pair of jacks on the first device.

4 . The method of claim 1 , wherein the Ethernet cable is coupled to at least one of a pair of terminal blocks on the first device.

5 . A first building device for a building system of a building, the building system comprising second building devices coupled by an Ethernet cable, wherein at least one of the second building devices is coupled to the first building device, the first building device comprising:

a plurality of transceivers each configured for a respective one of a plurality of protocols; and

one or more circuits configured to:

connect to the Ethernet cable;

determine a protocol for the second building devices;

select a transceiver from the plurality of the transceivers based upon the protocol; and

communicate with the at least one of the second building devices using the transceiver and the protocol, wherein the one or more circuits is configured to:

determine an end of line status for the first device; and

engage an end of line circuit in response to the end of line status.

6 . The first building device of claim 5 , wherein the transceivers are internal transceivers.

7 . The first building device of claim 5 , wherein the first building device is a controller comprising a pair of jacks.

8 . The first building device of claim 3 , wherein the jacks are at least one of RJ12, RJ45, or RS485 jacks.

9 . The first building device of claim 5 , wherein the jacks are configured to receive a plug associated with the Ethernet cable.

10 . The first building device of claim 5 , wherein the first building device comprises a sensor or actuator comprising a pair of jacks.

11 . The first building device of claim 5 , wherein the first building device is an air handler unit (AHU) package comprising a pair of jacks.

12 . The first building device of claim 5 , wherein the one or more circuits is configured to:

determine the end of line status for the first device by measuring impedance, providing polling signals, or receiving a microswitch signal.

13 . The first building device of claim 12 , further comprising a sensor configured to provide a sense signal indicative of the end of line status or a sensor configured to sense the protocol by sensing a type of plug connected to the jacks.

14 . The first building device of claim 7 , wherein the jacks are an RJ45 jack and at least one of another type of jack.

15 . A first building device for a building system of a building, the building system comprising second building devices coupled by an Ethernet cable, wherein at least one of the second building devices is coupled to the first building device, the first building device comprising:

an end of line circuit; and

one or more circuits configured to:

connect to the Ethernet cable;

determine an end of line status for the first building device; and

engage the end of line circuit in response to the end of line status.

16 . The building system of claim 15 , further comprising a pair of jacks for connecting to the Ethernet cable.

17 . The first building device of claim 16 , further comprising a sensor configured to provide a sense signal indicative of a connection to the Ethernet cable.

18 . The first building device of claim 17 , wherein the sense signal is provided by a switch disposed in one of the jacks.

19 . The first building device of claim 15 , wherein the end of line circuit comprises a resistive network coupled to at least one of the jacks.

20 . The first building device of claim 19 , wherein the resistive network comprises a shunt resistor, a pull up resistor and a pull down resistor.