Power supply for loop resistance testing and loop resistance tester

The embodiment of the invention discloses a power supply for loop resistance testing and a loop resistance tester. The power supply comprises a battery pack, a first capacitor, a charging and discharging circuit and a discharging circuit; the charging and discharging circuit is electrically connected with the battery pack and the first capacitor, and the first capacitor is also electrically connected with the discharging circuit; the charging and discharging circuit is used for transmitting electric energy of the battery pack to the first capacitor to charge the first capacitor in a first stage; the charging and discharging circuit is further used for connecting the battery pack and the first capacitor in series in the second stage, and the discharging circuit is used for jointly discharging and outputting electric energy stored by the battery pack and the first capacitor in the second stage. According to the technical scheme provided by the embodiment of the invention, the number of batteries is reduced, the