1. The power supply voltage range for driving this dual display meter is 4.5-30V. When the voltage of the tested circuit system meets this range, you can directly take electricity from the tested circuit. The thin red and black wires are the power connection wires; When the voltage of the test circuit system is higher than 30V. The dual display meter must be equipped with a special power adapter. The output voltage of the power adapter must meet the range of 4.5-30V. 5-20V is recommended first.
2. 100V10A is a built-in shunt, 100V50A and 100V100A need to use an external shunt: If an external shunt is required, before powering on the dual-display meter, you must first connect the dual-display meter and the shunt.
3. The current must be sampled from the low end, that is: the current of the tested circuit system first flows through the load, and then through the meter (or the shunt connected to the meter), otherwise, the dual display meter will be instantly damaged.
4. The concept of the power supply and load of the system under test: when discharging, the battery, switching power supply, transformer, etc. provide energy for the power supply; resistance, light, motor or other electrical appliances consume energy is the load, when charging, the charger, power generation Machines and solar panels are power sources, and various types of batteries being charged are loads.
5. W1 on the circuit board of this dual-display meter is a microword for measuring voltage calibration, and W2 is a microword for measuring current calibration: this dual-display meter has been accurately calibrated before leaving the factory, please do not adjust it at will:
6. The 100V50A and 100V100A dual display meters must be connected to the shunt of the corresponding range before they can be used, and the shunt must be connected to power on, otherwise it will cause instantaneous damage to the dual display. When connecting the shunt, the two large current wires should be fixed on the shunt wire, and the wire connected with the dual display meter should be connected to the small screw. Otherwise, it will cause great errors.
7. When there is a problem with connection or use, please refer to the following possibilities:
a. No display or abnormal display: This dual display meter requires a DC drive power supply, please check whether the power supply does not use large capacitors or the power supply ripple is too large;
b. The voltage display is normal, the current display is 0.00 or 0.0: the circuit sampling connection error will cause this situation, please go back to the precaution item 4 and refer to the wiring diagram to clarify the concept of power supply and load. Note that in the same system, the concepts of power supply and load are different when discharging and charging.
c. Inaccurate current display: When the ground of the driving power supply of the dual display meter and the ground of the system under test are in the same ground, please disconnect the thin black wire,
d. When the measured voltage or current is the answer, the display of the dual-display meter does not return to zero: first check whether the circuit is connected correctly, and secondly, check whether the driving power ripple of the dual-display meter is too large, and whether the sampling circuit is too long to cause interference, usually not It does not affect normal use when resetting to zero
