NON-CHARGING BATTERY BACKUP UNIT (BBU)

1 . A battery backup unit (BBU) comprising:

a housing;

at least one battery compartment in the housing including an output terminal;

at least one DC input;

a DC output;

a path from the at least one DC input to the DC output;

circuitry connecting the output terminal to the path and including a switch for selectively connecting the output terminal to the path, the circuitry precluding current flow from the at least one DC input to the output terminal; and

a controller configured to detect a condition of said path and to selectively control said switch when said condition is detected.

2 . The BBU of claim 1 wherein said condition is a voltage level on said path.

3 . The BBU of claim 1 , wherein said circuitry includes a DC/DC converter between the output terminal and the path.

4 . The BBU of claim 3 , wherein said DC/DC converter comprises a step-up converter.

5 . The BBU of claim 1 wherein said controller includes a first input receiving a signal indicative of the presence or absence of said condition and a first output connected to said switch.

6 . The BBU of claim 1 , wherein said housing includes at least one visual indicator providing a first visual indication when the condition is detected and a second visual indication different than said first visual indication when the condition is not detected.

7 . The BBU of claim 1 including at least one visual indicator providing a visual indication of a remaining life of a battery in said at least one battery compartment.

8 . The BBU of claim 1 including a voltage regulator connected to the path and to an input of the controller.

9 . The BBU of claim 1 , wherein said controller is configured to open said switch when an output from said output terminal is between a first level and a second level.

10 . The BBU of claim 1 including a data port and a conductor connecting said data port to said controller.

11 . The BBU of claim 1 including at least one battery removably mounted in said at least one battery compartment.

12 . The BBU of claim 1 including:

a DC/DC converter between the output terminal and the path,

wherein said controller includes a first input receiving a signal indicative of the presence or absence of a first level of DC power on said path and a first output connected to said switch, and

a voltage regulator connected between the path and a regulator input of the controller.

13 . The BBU of claim 12 , including a data port and a conductor connecting said data port to said controller, wherein said DC/DC converter comprises a step-up converter, wherein said controller is configured to open said switch when an output from said output terminal is between a first level and a second level and wherein said housing includes at least one visual indicator providing a first visual indication when the first level of DC power is present, a second visual indication different than said first visual indication when said first level of DC power is absent and a third visual indication of remaining life of a battery in said at least one battery compartment.

14 . A battery backup unit (BBU) comprising:

a housing;

at least one battery compartment in the housing including an output terminal;

a DC input;

a DC output;

a path from the DC input to the DC output;

circuitry for selectively connecting the output terminal to the path and including a switch; and

a controller configured to detect a condition of said path and to selectively control said switch to connect said output terminal to said path when said condition is detected,

wherein said BBU is incapable of charging batteries in said at least one battery compartment.

15 . The BBU of claim 14 wherein said condition comprises a voltage of said path.

16 . The BBU of claim 15 , including

a DC/DC converter between the output terminal and the path,

wherein said controller includes a path condition input receiving a signal when said condition is detected and a first output connected to said switch, and

a voltage regulator connected between the path and a regulator input of the controller.

17 . The BBU of claim 16 , including

a data port and a conductor connecting said data port to a data input of said controller,

wherein said DC/DC converter comprises a step-up converter, and

wherein said housing includes at least one visual indicator providing a first visual indication when the condition is detected, a second visual indication different than said first visual indication when the condition is not detected and a third visual indication of a remaining life of a battery in said at least one battery compartment.

18 . A battery backup unit (BBU) comprising:

a housing;

at least one battery compartment in the housing including a battery terminal;

a DC input;

a DC output;

a DC path from the DC input to the DC output; and

control means for controlling current flow at said battery terminal and circuitry means for selectively connecting said battery terminal to said path, said control means including a controller for detecting a condition of said path and for controlling said circuitry means to selectively connect said battery terminal to said path when said condition is detected.

19 . The BBU of claim 18 , wherein said condition comprises a voltage level on said path.

20 . The BBU of claim 18 , including at least one battery removably mounted in the at least one battery compartment, wherein said circuitry means precludes the recharging of said at least one battery while said at least one battery is mounted in said at least one battery compartment.