Manual Calibration

  • This calibration tool is an old version. Our latest BTS Client now has integrated calibration function. They have similar usage. Since NwCal.exe is largely used before. Below steps indicate how to calibrate neware battery testing sytem using this software.
  • NwCal uses RS232 or RS485 to communicate. So before you conduct the calibration work, you need to release the connection from bottom machine to middle machine, connect an RS232 cable directly from the middle machine to the host computer. If the RS232/RS485 port on the battery tester is 9-pin male port, use a 9-pin RS232/RS485 wire to connect computer to the computer’s COM port. If the RS232 / RS485 on the battery tester is RJ45 jack, use an adapter wire – one end is RJ45 and the other is COM port, or use an RJ45 straight through cable to black Port Adapter(if purchased) which uses USB or COM port to be connected with the computer.
  • Since models of different current ranges have different default segments for the calibration, you need to match the calibration segment ranges to the correct the battery tester you are going to calibrate. If your model has a current lower than or equal to 6A, use 1 segment. Use 3 segments if the current range larger than 6A. Voltage and current will have the same number of segments.

calibration segments settings

Figure 80 : Calibration Segments Settings

  • Click OK and exit the program. After you connect the bottom machine to the host computer with RS232 cable, you can re-launch this program. The program will search for the units automatically. Click Yes to load the calibration data for the connected unit.

load calibration data

Figure 81 : Load Calibration Data

  • In the right area, there are channels listed, type of accuracy test and calibration mode for your choice, and if this unit is a main channel, there will be 4 items needed to calibrate – CC (Charge Current), CV (Charge Voltage), DV (Discharge Voltage) and DC (Discharge Current). If you are calibrating current and the circuit uses a shunt, you need to select Shunt choice from the Digital Multi-Meter field, and input an accurate value for resistance.

calibration overview

Figure 82 : Calibration Overview

  • Clicking Run will measure the battery testing system response to the calibration. You will also obtain a value from the meter you connected – current or voltage based on the item you selected and the circuit you connected. If you choose current calibration and your circuit has a shunt, you can only input the voltage readings into the Meter Value box– the program will calculate the equivalent current based on the voltage and the resistance.
  • Now Click Run again, program will measure the battery testing system response at another point of the segment. Input the meter value as performed in the above procedure. If all points for this item of the channel have been finished, the program will jump to the next channel for calibration. Now you can move onto next item like CC (Charge Current).
  • If you do not have battery testing system powered with negative power supply and no available battery function as an external power source, you may choose Copy KB Value on the right click menu after you have finished CC (Charge Current) calibration. Similarly, when you do not have a digital voltage signal source, you may choose Copy KB Value after you have finished CV (Charge Voltage) calibration.

copy kb value

Figure 83 : Copy KB Value

When all items of all channels have been calibrated, you now click Write KB(W) to save all the calibration data. Restart to enable changes.