The cable outer sheath fault tester XHHG521A is designed based on the MURRAY bridge principle and can be used to locate the breakdown points of various wires and cables and the defect points that have no breakdown but low insulation resistance values.
The equipment uses an electric voltage regulator and an R-type transformer to form a high-voltage constant current source, and the button operation can increase or decrease the voltage. The no-load voltage is 7500V, the short-circuit current is 100mA, and a high-sensitivity amplifier and galvanometer are used to indicate balance. It forms a balanced bridge with a proportional potentiometer, and the whole is placed at a high potential. The measurement cable is a specially designed two-core high-voltage rubber cable. The four-terminal resistance measurement method is used to avoid errors caused by lead resistance. The entire panel is at low potential. One-touch operation, enter the cable length and automatically calculate the fault distance. The high voltage source and bridge are integrated in a portable protective box. Therefore, the device has high voltage, light weight, easy operation and safe use.
Technical parameters
No load voltage
≥7500V
Short circuit current
≥100mA (when adjusting balance, it is recommended to set it at 5~40mA);
Positioning accuracy
±(0.2%·L±1)m
Weight
25kg
Power supply
AC 220V (±10%), 50Hz±1Hz; 8.4V built-in battery.
Product feature
1. Output voltage is adjustable; 2. Has high accuracy and stability; 3. Adopt high-sensitivity amplifier and galvanometer to indicate balance; 4. Zero protection; 5. Automatically test fault points, but retain manual testing functions; 6. Compared with the wave reflection method, the bridge balance method has no blind area and is used to determine the breakdown point of short cables and near the ends.