BRS BIM1, Instruction Manual, Page: 13 / 36

Battery Impedance Meters
BRS Messtechnik GmbH Page 13 of 36 Version 1.7 / April2015
Since the impedance decreases with the frequency, the measurement range should
be oriented towards the lowest frequency to be measured.
The measurement current is set automatically, depending on the range; a lower
range has a higher current.
During impedance measurements the battery is loaded and the re-
sulting power has to be dissipated within the instrument. This power
has to be lower than 6W. Thus please note the following derating for
the battery voltages:
Measurement range Average current Max. Voltage
3mΩ
500mA 12V
1mΩ
1000mA 6V
b) Measurement frequency
The measurement frequency can be set between 0,1Hz (1Hz with BIM1) and 1kHz in
quasi-logarithmic step with 6 values per decade.
The lower the frequency, the longer the measurement time. It is therefore sensible to
work with as high a frequency as possible.
4.4 Battery discharge during extended use
When taking measurements over an extended period, please note that the meas-
urement device works in a unipolar manner. This means that the test item will be dis-
charged with 50% of the measurement current.
Please take care to ensure that the battery is not completely dis-
charged. You can use the integrated voltage monitor for this.
Please be aware that even when disconnected the input resistance of
the voltage
measurement of around 50 kΩ lies in parallel to the bat-
tery clips. You should therefore completely disconnect the measurement device
when no measurements are being carried out over an extended period.