Pay attention to these matters when configuring UPS power

When considering the capacity problem in the process of selecting the UPS power supply in the equipment room, the relevant factors determining the size of the capacity should be listed, and the specific relationship between each factor and the capacity should be specified. The reference factors for determining the UPS capacity are: actual load capacity, type of load, capacity utilization rate, environmental conditions, type of UPS and actual load capacity, and potential capacity expansion requirements.

Practical applications should consider:

1, the actual load capacity

This is the fundamental factor in determining the size of the UPS power supply. The output capacity of the UPS power supply must meet or exceed the load requirements to ensure normal power supply. In practical applications, it is necessary to consider whether the UPS power supply is centralized or distributed. The total amount of load using centralized power supply should be the cumulative power of all the power supplies supplied by the UPS in the equipment room. The use of distributed power supply is determined according to the load of each UPS.

Usually the load capacity of an electrical device is called apparent power, expressed in S, in VA. The apparent power includes active power P (unit W) and reactive power Q (unit Var), and the relationship of the magnitude is S2 = P2 + Q2. Here we refer to the ratio of active power to apparent power as power factor, the power factor of pure resistive load is 1, and the power factor of capacitive load is generally 0.6~0.7.

2, the type of load

As mentioned above, different types of loads have different ratios of active power and reactive power, but the UPS needs to provide sufficient active power and reactive power to the load at the same time, and the actual output capability is limited by the type of load. For computer type loads, the UPS can basically output the rated power. If the load is resistive or inductive, the output power of the UPS is reduced, and the UPS capacity needs to be increased. For example, a 1KVAUPS with a power factor of 0.7 can carry a full load of 1KVA with a computer load, a 700VA with a purely resistive load (700W at this time), and a lower with an inductive load. Therefore, when calculating the load capacity, the resistive and inductive loads expressing power in W value should be converted into VA values. Generally, the calculation method is: VA value of resistive load = W value ÷ 0.7; VA value of inductive load = The W value is ÷0.3.

3, UPS power capacity utilization rate

Since the computer room equipment has various non-linear loads of various switching power supplies and various types of printer loads, these loads have large inrush current. If the power supply UPS capacity is too small, long-term heavy-duty operation is prone to waveform distortion, and it is easy to cause output final power. Over-current of the device, coupled with the heat generated by heavy loads, is significantly detrimental to system reliability. For high power UPS, it is generally recommended that the capacity usage be controlled at 0.6~0.8.

Of course, the UPS capacity should not be too large. Although the UPS has a small load, it is good for reliability, but excessive light load operation is a waste of investment. Second, when the utility power is cut off for a long time, the battery has been discharged with a small current, which is prone to damage caused by deep discharge.

4. Environmental conditions

The operating temperature of the UPS should generally be controlled within the range of 0~40 °C. If the temperature is too high and the ventilation conditions are not good, it is not conducive to heat dissipation and should be derated. In addition, the altitude also has an impact. For every 1000m increase after an altitude of more than 1000m, the UPS should be derated by 5%.

5, UPS type and actual load capacity

Different types of UPS have different loading capacities. The output capability of the power frequency machine is better, and the actual load capacity of the high frequency machine is only 0.9 times that of the power frequency machine.

In other manufacturers' products, there may be a phenomenon that the actual load capacity is lower than the nominal capacity. This is a credibility problem of the product, and the user has to consider this factor when applying. The products produced by Ou Meimei Company have undergone rigorous testing and quality control, and users can be assured.

6, the potential expansion of equipment needs

The UPS capacity should be considered in consideration of the future expansion of the equipment, leaving a certain margin, and the load will increase in the future, so that the UPS will not be purchased again. In addition, try to use a model with parallel function, and if necessary, expand the output capacity by UPS. At the same time, when configuring the input and output power distribution cabinet of the UPS, the cable and the air supply should be left with a certain margin to facilitate future capacity expansion.