Power supply unit
A power supply unit for supplying power to a device has a rechargeable, main battery; a charging arrangement for charging the main battery; a non-rechargeable back-up battery; load terminals for connection to a load; and a control unit for controlling supply of power to the load primarily from the main battery and secondarily from the back-up battery. The device is, in particular, a single bay, stand alone parking meter. In the event that the main battery runs low, the control unit is configured to supply power to the load from both the main battery and the back-up battery or only from the back-up battery. The back-up battery is easily replaceable, and the power supply unit has a bay, with connectors for receiving the back-up battery. The main battery is charged from solar panels. A communication device is provided to communicate status messages wirelessly to a control system.
1. A parking meter comprising:
a) a housing;
b) a rechargeable battery;
c) a wireless communication device for communicating a status message regarding the status of the rechargeable battery to a control system external to the parking meter;
d) a non-rechargeable back-up battery; and
e) a control unit for monitoring the status of the rechargeable battery and signaling the wireless communication device to communicate the status message;
wherein the rechargeable battery, the non-rechargeable battery, the wireless communication device, and the control unit, are received within the housing of the parking meter.
2. The parking meter of claim 1 , wherein the rechargeable battery consists of one to five cells.
3. The parking meter of claim 1 , wherein the control unit monitors the status of the voltage across the rechargeable battery.
4. The parking meter of claim 3 , wherein the control unit signals the wireless communication device to communicate the status message when the voltage across the rechargeable battery drops below a predetermined level.
5. The parking meter of claim 4 , wherein the predetermined level is 5.5V.
6. The parking meter of claim 1 , wherein the status message comprises: voltage across the battery, remaining battery charge, remaining battery life, error message indicating battery failure, or a combination thereof.
7. The parking meter of claim 1 , wherein the wireless communication device communicates the status message over a telecommunications network.
8. The parking meter of claim 1 , wherein the parking meter is a single space parking meter or a dual space parking meter.
9. The parking meter of claim 1 , wherein the parking meter is a multi-space parking meter.
10. A power supply for a parking meter comprising:
a) a rechargeable battery;
b) a connection to a wireless communication device for communicating a status message regarding the status of the rechargeable battery to a control system external to the parking meter;
c) a non-rechargeable back-up battery; and
d) a connection to a control unit for monitoring the status of the rechargeable battery and signaling the wireless communication device to communicate the status message;
wherein the rechargeable battery, the non-rechargeable back-up battery, the wireless communication device, and the control unit, are received within the parking meter.
11. The power supply of claim 10 , wherein the rechargeable battery consists of one to five cells.
12. The power supply of claim 10 , wherein the control unit monitors the status of the voltage across the rechargeable battery.
13. The power supply of claim 12 , wherein the control unit signals the wireless communication device to communicate the status message when the voltage across the rechargeable battery drops below a predetermined level.
14. The power supply of claim 13 , wherein the predetermined level is 5.5V.
15. The power supply of claim 10 , wherein the status message comprises: voltage across the battery, remaining battery charge, remaining battery life, error message indicating battery failure, or a combination thereof.
16. The power supply of claim 10 , wherein the wireless communication device communicates the status message over a telecommunications network.
17. The power supply of claim 10 , wherein the parking meter is a single space parking meter or a dual space parking meter.
18. The power supply of claim 10 , wherein the parking meter is a multi-space parking meter.
19. A method for managing the supply of power to a parking meter comprising:
a) monitoring, by a control unit, the status of a rechargeable battery and a non-rechargeable back-up battery; and
b) signaling, by the control unit, a wireless communication device to communicate a status message to a control system external to the parking meter regarding the status of the rechargeable battery;
wherein the rechargeable battery, the non-rechargeable back-up battery, the wireless communication device, and the control unit are received within the parking meter.
20. The method of claim 19 , wherein the rechargeable battery consists of one to five cells.
21. The method of claim 19 , wherein the status of the rechargeable battery monitored comprises the voltage across the rechargeable battery.
22. The method of claim 21 , wherein the signaling is triggered by the voltage across the rechargeable battery dropping below a predetermined level.
23. The method of claim 22 , wherein the predetermined level is 5.5V.
24. The method of claim 19 , wherein the status message comprises: voltage across the battery, remaining battery charge, remaining battery life, error message indicating battery failure, or a combination thereof.
25. The method of claim 19 , wherein the wireless communication device communicates the status message over a telecommunications network.
26. The method of claim 19 , wherein the parking meter is a single space parking meter or a dual space parking meter.
27. The method of claim 19 , wherein the parking meter is a multi-space parking meter.