Reporting power requirements of a powered device

1. An apparatus, comprising:

a line side configured to receive power from an external power source;

a circuit on the line side configured to send a first signal to at least one installed module the circuit comprising an analog to digital converter for receiving the response to the first signal;

an isolated side isolated from the line side, wherein the at least one module is located at the isolated side;

an isolation barrier between the line side and the isolated side to provide isolation between the line side and isolated side;

wherein the circuit on the line side is configured to send the first signal across the isolation barrier to the isolated side;

wherein the circuit is configured to determine a power requirement for the at least one installed module based upon a response to the first signal; and

wherein the circuit is responsive to determining the power requirement for the at least one installed module to send a second signal to the external power source, the second signal comprises data representative of the power requirement.

2. An apparatus according to claim 1 , the first circuit further comprises a voltage divider for receiving the response to the first signal coupled between the isolation barrier and the analog to digital converter.

3. An apparatus according to claim 2 , the first circuit comprises a diode coupled between the voltage divider and the analog to digital converter.

4. An apparatus according to claim 3 , wherein the diode is a schotkey diode.

5. An apparatus according to claim 4 , the isolation barrier comprises first and second capacitors, the first capacitor coupled to the installed module for providing the first signal to the installed module, the second capacitor coupled between the installed module and the voltage divider.

6. An apparatus according to claim 1 , the installed module further comprises a plurality of installed modules.

7. An apparatus according to claim 6 , the isolation barrier comprises a plurality of capacitors corresponding to the plurality of installed modules, coupled between the first circuit and the plurality of installed modules for providing the response of the plurality of modules to the first circuit.

8. An apparatus according to claim 7 , wherein the first circuit is configured to determine the power requirement for each of the plurality of installed modules individually.

9. An apparatus according to claim 8 , the first circuit further comprises a plurality of analog to digital converts corresponding to the plurality of installed modules for determining the response to the signal from each of the plurality of installed modules individually.

10. An apparatus, comprising:

means for receiving power from an external power source;

means for determining a power requirements for at least one installed module separated from the external power source by an isolation barrier;

means for communicating the power requirements for the at least one installed module to the external device;

means for receiving available power from the external power source;

means for reconfiguring the installed module to conform with the available power from the external power source; and

means for communicating the power requirement for the reconfigured installed module to the external power source.

11. An apparatus, comprising:

a line side configured to receive power from an external power source;

a first circuit on the line side configured to send a first signal to at least one installed module;

an isolated side isolated from the line side, wherein the at least one module is located at the isolated side;

a second circuit on the isolated side;

an isolation barrier between the line side and the isolated side to provide isolation between the line side and isolated side, the isolation barrier further comprising an optical link coupling the first circuit to the second circuit;

wherein the first circuit is configured to send the first signal across the isolation barrier to the isolated side

wherein the first circuit is configured to determine a power requirement for the at least one installed module based upon a response to the first signal; and

wherein the first circuit is responsive to determining the power requirement for the at least one installed module to send a second signal to the external power source, the second signal comprises data representative of the power requirement.

12. An apparatus according to claim 11 , wherein the first circuit is configured to receive data representative of available power from the external power source, the first circuit being responsive to receiving the data representative of available power to communicate the data representative of available power to the second circuit via the optical link.

13. An apparatus according to claim 12 , wherein the second circuit is responsive to receiving the data representative of available power to reconfigure the installed module to operate within the available power.

14. An apparatus according to claim 13 , wherein the second circuit communicates the power requirement for the reconfigured installed module to the first circuit via the optical link.