Saitreg Fuel Nozzles Fuel Nozzles and Pumps

Fuel Flow Gauge

Fuel Flow Gauge

In part 1 of Dissecting A Smart Battery I mentioned that smart batteries have contained within them specialized hardware that when working in concert provides the power necessary to run a device such as a PDA, digital camera, or ipod player. Continuing the dissection of a smart battery this article of the series will look at the smart battery's fuse, charge and discharge FETs , the cell pack, and the sense resistor (RSENSE) to discover what role they each play within the smart battery.

Before we begin let's just recap some of the specialized hardware within the smart battery:

1. the connector
2. the fuse
3. the charge and discharge FETs
4. the cell pack
5. the sense resistor (RSENSE)
6. the primary and secondary protection ICs
7. the fuel-gauge IC
8. the thermistor
9. the pc board
10. the EEPROM
11. the SMBus

The Smart Battery Fuse

When we discuss fuses in relation to electronics we are speaking directly of a fusible link that is responsible for protecting the device from over current. Fusible links have a metal wire that melts when heated to a predetermined electric current rating. When melted the electrical circuit is opened and thereby protecting the circuit from an over-current condition. The obvious concern here is the selection of the fuse - an improperly selected fuse will not protect from over-current conditions and the result will be a fire or damage due to a short circuits.

In a smart battery a typical fuse has three-terminal components that limit current flow based on the temperature, current, and or power across the heating wire. Besides temperature ratings other important factors when selecting the proper fuse to work with each smart battery is hold current, trip current, maximum battery voltage, and fuse size.

The Smart Battery's FET (field effect transistor)

Smart batteries must have a series FET (field effect transistor) switch to open and protect the battery's cells. A FET is a transistor that uses an electric field to control the conductivity of a particular 'channel' in a semiconductor material. FETs at times are used as voltage-controlled resistors. As such field effect transistors are chosen based upon their designed ability to dissipate on demand power.

The Smart Battery's Cell Pack

The battery cell can be thought of as the holding area of the battery's chemical. The battery cell pack is critical to the overall capability of the smart battery. Cell packs have to be designed and integrated based upon the vitals of the battery including chemistry type (Li-ion, Li-po, NICD, NIMH, etc.) cycle life, storage-capacity loss, shelf life, impedance, capacity at different rates of discharge and temperature, and mechanical and environmental requirements. It is critical to say the least.

The Smart Battery's Sense Resistor

The final specialized hardware I want to review in this article is the sense resistor (RSENSE). In electronics, sense, is generally referred to the task of producing the correct voltage. Current not temperered will cause damage so sense resistors need to be integrated in order to control power and temperature.

In my next article on the dissection of a smart battery I will cover secondary protection ICs, the fuel-gauge IC, the thermistor, the pc board, and the EEPROM.

© Dan Hagopian You have permission to publish this article electronically or in print, free of charge, as long as the bylines are included with link. Dan Hagopian of http://www.batteryship.com is a known electronics author that specializes in portable power gadgets. His work can be found on the BatteryShip blog at http://www.batteryeducation.com He frequently writes about pda batteries, ipod batteries, general battery technology for our mobile world, new fuel cell technology and interesting power related inventions. For further information please visit http://www.batteryship.com where you can also find PDA battery replacement kits, smartphone batteries, twoway radio batteries, barcode scanner batteries, camera batteries, and camcorder batteries.

Fuel Gauge by Omix-Ada $34.99 Fuel Gauge; Original Design

Fuel Pressure Gauge $43.99 Fuel Pressure Gauge

Fuel Pressure Gauge Kit $77.99 Fuel Pressure Gauge Kit; w/Fuel Injection;

Fuel/Temp Gauge $45.99 Fuel/Temp Gauge; Original Design;

High Flow Fuel Pump Fitting $30.99 High Flow Fuel Pump Fitting;

Fuel Gauge by Crown Automotive $69.99 1992-95 Jeep YJ Wrangler;Unleaded fuel only;Indash gauge Fuel Gauge by Crown Automotive

Fuel Pressure Gauge for Jeep $38.99 0-30 psi;Liquid filled;1.5 in. Fuel Pressure Gauge for Jeep

Cobra Fuel Pressure Gauge $144.99 Cobra; Fuel Pressure Gauge; 2-1/16 in.; 0-15 PSI; Black Dial Face;

Fuel Gauge Autometer Fuel Gauge 5716 $53.93 AUTOMETER PHANTOM ELECTRIC FUEL GAUGE -- 2.06 in. diameter; 240 ohms empty and 33 ohms full range; Includes red and green bulb covers for a customized look; With white illumination around the dial, red pointer for quick glance monitoring, and black bezel; Features air core meter movement, precision movement, and extreme accuracy; Safeguards against dangerous conditions; For use with fuel level sender 3262; Recommends fuel level sender, gauge mounting cup, gauge panel, mounting angle ring, and tachometer bracket.. Auto Parts Warehouse has extensive Autometer Fuel Gauge catalogs.We are now offering FREE shipping on all Autometer Fuel Gauge orders over $50.00. Our secure autometer fuel gauge catalog is available every hour of everyday. Shop with confidence for all your autometer fuel gauge needs. Autometer Fuel Gauge are In Stock and available today. Save up to 60% off dealer price on your next Autometer Fuel Gauge purchase. Our online catalog contains a wide selection of the OEM and aftermarket parts you need at unbeatable prices

MSD Fuel Level Gauge $171.99 2-5/8 in.; Fuel Level; Programmable;

Fuel Gauge Autometer Fuel Gauge 1315 $36.05 autometer street rod arctic white fuel gauge 2.06 in. 0 ohms empty and 90 ohms full range includes red and green bulb covers for a customized look with 40 to 250 ohms sender chromed bezel domed lens and white illumination around the dial includes red and green bulb covers features quality construction and a nostalgic look recommends fuel rail adapter gauge mounting cup gauge panel and mounting angle ring auto parts warehouse has extensive autometer fuel gauge catalogs.we are now offering free shipping on all autometer fuel gauge orders over $50.00. our secure autometer fuel gauge catalog is available every hour of everyday. shop with confidence for all your autometer fuel gauge needs. autometer fuel gauge are in stock and available today. save upto 60% off dealer price on your next autometer fuel gauge purchase. our online catalog contains a wide selection of the oem and aftermarket parts you need at unbeatable prices

Maretron / Maretron FFM100 Fuel Flow Monitor / FFM100-01 $335.4 Maretron - Maretron FFM100 Fuel Flow Monitor - FFM100-01

Cruiser; Fuel Level Gauge $73.99 Cruiser; Fuel Level Gauge; 2-1/16 in.; 0 Ohms Empty; 90 Ohms Full; For Most Chevy/GM 1965-97;

Nexus Fuel Level Gauge $139.99 Nexus; Fuel Level Gauge; 2-1/16 in.; 0 Ohms Empty; 0 Ohms Full;