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Applications: Data Acquisition
In short, when you charge or discharge a battery string, if you need to know the curve of each cell, you will need data acquisition device like BatteryDAQ.
The difficulties of battery testing have often been overlooked:
- High voltage, a battery powered tool may use 36V or 48V. The regular data acquisition card can only receive +/-20V.
- Reliable link, battery stores high energy, any unsecured wire may cause shortage/damage.
- Many other issues, if you have been doing battery testing, you knew them.
* You don't need RM module if you don't need IR (Internal Resistance) data.
Electric Vehicle Battery Test Kit
Comparison between BatteryDAQ and regular DAQ cards/Modules
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BatteryDAQ |
Regular DAQ cards/modules |
Common Voltage |
+/-400V |
+/-20V |
Input Voltage |
+/-20V |
+/-20V |
Isolation |
500V |
Non-isolated |
Channel |
30 DI (Differential Input)
59 SE (Single wire)
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16 DI
32 SE
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Indicator |
2-color LED for each channel to indicate scanning position or alarm for each channel |
No consideration |
Resolution |
16 bits (1mV resolution) |
16 bits |
Current Sensor |
Supports 2 current sensors, compatible with I or V output. No additional power supply needed. |
No consideration. May use voltage channel with additional power supply. |
Temperature Sensor |
1 On-board sensor and 1 digital sensor interface |
Thermocouple to voltage channel |
Digital I/O |
Critical alarm output |
16 DI/O |
Sample Rate |
About 10S/s after digital filtering. |
About 100kS/s, you process noisy data afterwards. |
Input Connector |
Phoenix Contact 5.08mm industrial connectors. |
May need expansion board. |
Installation |
DIN rail or panel mounting |
PC Card or USB module |
Interface |
RS232/485, up to 1200 meters (4000 feet) distance |
PCI, USB , limit distance. <5 meters |
Communication |
Modbus RTU industrial standard |
Not transparent to user |
Working Experience |
- Install Modbus drive in PC.
- Copy Excel sheet.
- Link the RS-232 cable.
- Screw the battery testing wires directly to convenient 5.08mm plugs.
- Power on the power adapter.
- See the data in Excel sheet.
- Charge/discharge your battery, see the curve.
- Take the module with your jig out of your lab for a road/field test.
- Make a nice presentation with Excel data processing.
- Have fun building more sophisticated systems with DOT NET , LabVIEW, Matlab, Oracle, MySQL, XML etc.
- Later, try to check your battery real-time data through www.mybattery.info at home or on the road.
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- Install the software package.
- Install the DAQ card/module.
- Test the DAQ. Success!
- Install the extension module for wiring.
- Wire to batteries.
- Encounter >20V common voltage, add resistor divider to each input channel. (Engineers always have solutions.)
- Add additional power (+/-12V) to current sensor.
- Find out the accuracy getting worse as the common voltage goes higher.
- You decide to accept the tolerance.
- Now its time to test your battery on the road. This proves to be difficult due to the unreliable connections.
- Finally, go with BatteryDAQ
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Price |
$1850 per module |
$1000 to $2500 |
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