A brief introduction to resistance load boxes

Resistance load box is mainly used for performance testing and aging of online high-power UPS, inverter, switching power supply and diesel generator sets in power, telecommunications and other departments and manufacturers. Unified segmented power input, energy consumption working mode, forced air cooling heat dissipation, greatly ensure the reliability of constant power discharge; internal heat dissipation components use dry resistors and forced air cooling heat dissipation. Produced with new power consumption components with independent intellectual property rights, it has high power density, no red heat phenomenon, automatic overheating protection function, and will not overheat or burn when the fan does not rotate, and has a long safety life; the whole machine adopts modular design, simple operation and convenient maintenance; it can test voltage, current and other parameters according to customer requirements, providing scientific testing methods for high-power AC power supply equipment.

Resistance load box is divided into: DC load box and AC load box
1. Main functions:
1. The discharge power can be set and adjusted according to performance parameters and testing requirements.
2. The discharge time can be set: the load is automatically turned off when the timing time is reached.
3. The digital meter displays the values ​​of parameters such as voltage and current.
4. The whole machine adopts new power consumption components and has the protection function of automatic overheating blocking.
5. The AC load box (cabinet) has various specifications and a complete series. There are pure resistive loads or resistive, inductive, and capacitive loads.
6. It has the function of parallel connection.
II. Function selection
1. Resistive load cabinet [1]: Digital meter displays: power, voltage, and current detection values.
2. Intelligent AC load cabinet (LED): 0.5-level multifunctional digital special instrument, detects and displays: AC voltage, current, active power, power factor, and frequency. It can communicate with a PC through the RS485 microcomputer interface.
3. Intelligent AC load cabinet (LCD): Special LCD instrument displays: AC voltage, current, active power, power factor, voltage frequency; and has 1-40th harmonic analysis. It can communicate with a PC through the RS485 microcomputer interface.
3. Supplementary functions of the resistive load box ACLT
1. The inductive current values ​​of the three phases ABC and the capacitive current values ​​of the three phases ABC are directly and independently displayed on the control panel, and the symptoms of the AC resonance point are directly displayed on the panel.
2. The minimum standard power of the resistive load, inductive load and capacitive load built into the ACLT is 0.01K, the step amplitude is 0.01K, and the load power is continuously adjustable, which can accurately simulate the occurrence of AC resonance and meet the detection needs of the inverter anti-island protection function.
3. The resistive load uses alloy resistance elements, and the test process will not cause thermal drift of the resistance value due to the heating of the resistive load elements.
4. The built-in inductance of the ACLT uses a magnetic circuit controllable load inductance load element, which meets the 0.01KVA power regulation requirements under 220V/50Hz working conditions, and meets the inductance impedance power will not change during the long-term loading test process.
5. The inductive load uses low-loss components to ensure that the current harmonics (THD) of the inductive load under the nominal working voltage does not exceed 2%, and the resistive parasitics contained in the inductive components above 10K are less than 1%.
6. The built-in capacitor uses UL certified standard CBB capacitors to meet the 0.01KVAR power regulation requirements under 220V/50Hz conditions, and to ensure that the capacitance impedance power will not change during the long-term loading test process.
7. Each branch of the ACLT built-in capacitive load must be equipped with a special short-circuit protection circuit module to prevent the capacitor components from short-circuiting and burning the host during the test process.
8. The resistive and inductive parasitics contained in the built-in capacitive load components are less than 1%.
9. The power of the ABC three-phase resistive load, inductive load, and capacitive load can be independently controlled and adjusted in phase to meet the precise adjustment of the AC resonance point under the condition of unbalanced three-phase voltage.
According to the performance parameter detection requirements, the corresponding power can be set through the operation panel or remote console, and the discharge power can be set in any combination.