Power distribution installation
The difference between single input and dual input
Single input means that the rectifier and bypass share a switch input into the UPS. Dual input means that the UPS can allow the rectifier and bypass to have different switches, allowing dual power supplies to enter the UPS side at the same time. Single entry is relatively cheap, while double entry is more secure.
When there is only one switch in the application scenario, is it necessary to use the dual-input connection method?
Even if there is only one power supply, when the dual-input connection method is used, after the rectifier input fails, the UPS can still ensure the operation of the load equipment through the bypass input. In the single-input connection method, once a power failure occurs, the load will be powered off, causing losses to the user.
Application of leakage protection switch
The leakage protection switch cannot be used at the input end of the UPS. In the process of UPS inputting through the mains, there will generally be leakage current from the ABC three-phase to the ground, especially when the waveform is not good, the UPS will have a corresponding filter circuit to filter. Therefore, there must be leakage current at the input end. At this time, the leakage protection switch will not work, and may even cause interference. A leakage protection switch can be configured at the output end of the UPS, that is, the front end of the electrical appliance, which can play a protective role.
Selection of UPS grounding wire diameter
Even when the three-phase load is basically balanced, the wire diameter of the neutral wire should be thicker or even double the wire diameter of the phase wire; theoretically, the thicker the ground wire of the UPS, the better, and the diameter of the phase wire should not be smaller than the minimum requirement. ; It is better that the ground wires of the battery cabinet and electrical equipment can be connected to the ground terminal of the UPS and then into the ground.
Length requirements for input and output lines in parallel
The total length difference between the input and output lines of each machine is controlled to be less than 10% to ensure equal current distribution when switching to bypass.
When paralleling, all machine bypasses must be of the same source (basic requirement)
Bypassing different sources in parallel will result in failure to synchronize or even cause the UPS to fail to work.
battery installation
Battery cable requirements
The connecting wires between the batteries and the connecting wires from the battery cabinet to the UPS input terminal should use multi-core/copper/flexible wires, or copper bars; when the battery pack is far away from the UPS, it is required to increase the wire diameter. The principle is that under full load current, the cable The voltage drop is not more than 1% of the total battery voltage.
Application of Battery Switch/Output Switch Auxiliary Contacts
If the auxiliary contacts and release of the battery switch are configured on site, and there are group switches on site, it is recommended that all auxiliary contacts of the sub-switches need to be connected in series, and the release only needs to be added to the main switch. If there is no main switch, then the tripping The signal needs to be connected to each switch in parallel; the building alarm signal sent to the UPS externally, or the dry contact signal, the voltage cannot be higher than 25V AC/50V DC, (the safety voltage required by EHS), and the current cannot be greater than 1A; It is better to have a main output switch, otherwise it is inconvenient to switch from the maintenance bypass to the UPS without power interruption. The 1+1 parallel machine can be switched through a single output switch.
Precautions
UPS is not scaffolding
During installation, remember not to drop any foreign objects into the UPS, which will bring catastrophic results; remember not to remove the cover on the machine before starting the machine; during ground construction, cover the UPS to avoid falling It is difficult to clean up foreign objects falling into the machine; serious damage to the machine will occur when the machine is powered on.
When installing, consider the convenience of future maintenance
It is necessary to leave room for maintenance, and do not place it under the air outlet of the air conditioner to prevent condensation water from dripping into the machine.
What is a qualified installation?
The yellow, green and red marks are clear, the wiring is neat, horizontal and vertical, the strapping is perfect, and the cable ties are cut flat.
What is a good installation?
After all the copper noses are pressed with hydraulic pliers, they are wrapped with insulating paper tape, and then tinned in a small tin furnace; at least one meter of yellow, green and red heat shrinkable sleeves are placed on both terminals of each cable, and then heated with a heat gun. There is a sign at both ends of each cable, indicating where it comes from, where it goes, and how long the cable is; all signal lines other than power lines need to pass through shielded steel pipes.
How to protect field equipment?
After unpacking, it is necessary to protect the equipment from dust. For example, if the wind blows from the top, it needs to be shielded at the top; when constructing the input and output wiring cabinet, you need to pay attention to protecting other components. And contact the service engineer in advance to confirm whether there is any impact; the removed door panels, screws, etc. need to be kept well; the random clips, screws, manuals and other accessories also need to be kept well; the SN number of all equipment, please accurately record ( Best to take pictures).
UPS is safe, and installation requirements are recorded first.
The wiring rules are neat and smooth, and the thickness of the wire diameter should be distinguished.
Yellow, green, red and blue flower arrangement lines, the phase sequence can never be disordered.
Consider single and double input, stability and safety are very important.
The neutral wire is not thinner than the phase wire, and the diameter of the ground wire should be paid more attention.
The batteries should be placed neatly, leaving room for maintenance.
AC replaces DC, and the two contacts are positive in series.
The top cover of the machine is not opened to prevent foreign objects from falling into it.
There is a lot of dust in the ground construction, and the machine must be wrapped.
