| CPC G01R 31/389 (2019.01) [G01R 31/3646 (2019.01); G01R 31/371 (2019.01); G01R 31/3842 (2019.01)] | 7 Claims |

|
1. A clamp meter system with a battery-internal-resistance-measuring function applied to a plurality of batteries, the batteries connected in series with each other and electrically connected to the clamp meter system, the clamp meter system comprising:
a first processing unit;
an analog-to-digital converting circuit electrically connected to the first processing unit;
a current-measuring circuit electrically connected to the analog-to-digital converting circuit;
a direct-current current sensor electrically connected to the current-measuring circuit;
a voltage-attenuating network electrically connected to the analog-to-digital converting circuit;
a voltage probe set electrically connected to the voltage-attenuating network and the batteries;
a first wireless communication transceiver circuit electrically connected to the first processing unit;
a second wireless communication transceiver circuit electrically connected to the first wireless communication transceiver circuit; and
a second processing unit electrically connected to the second wireless communication transceiver circuit,
wherein the first processing unit is configured to use the analog-to-digital converting circuit, the current-measuring circuit, the direct-current current sensor, the voltage-attenuating network—and the voltage probe set to measure a battery current and a battery total voltage of the batteries to obtain a second digital current signal and a second digital voltage signal; the first processing unit is configured to subtract the second digital voltage signal from a first digital voltage signal to obtain a voltage difference; the first processing unit is configured to subtract a first digital current signal—from the second digital current signal to obtain a current difference; the first processing unit is configured to divide the voltage difference by the current difference to obtain an overall internal resistance value of the batteries;
wherein at a first time point, the first processing unit is configured to use the analog-to-digital converting circuit, the voltage-attenuating network and the voltage probe set to measure the battery total voltage of the batteries to obtain the first digital voltage signal; the first processing unit is configured to set the first digital current signal to be zero; at a second time point, the first processing unit is configured to use the analog-to-digital converting circuit, the current-measuring circuit, the direct-current current sensor, the voltage-attenuating network and the voltage probe set to measure the battery current and the battery total voltage of the batteries to obtain the second digital current signal and the second digital voltage signal;
wherein the first processing unit is configured to transmit the overall internal resistance value of the batteries to the second processing unit through the first wireless communication transceiver circuit and the second wireless communication transceiver circuit; the second processing unit is configured to compare the overall internal resistance value of the batteries with an overall internal resistance threshold value; when the overall internal resistance value of the batteries is greater than the overall internal resistance threshold value, the clamp meter system is configured to perform a respective battery internal resistance measuring procedure on each of the batteries to measure an internal resistance value of each of the batteries.
|