Free Huawei H20-923_V1.0 Practice Exam with Questions & Answers

As data center power density increases (especially driven by AI and high-performance computing), the industry trend is to adoptliquid coolingin high-density scenarios because liquid has much higher heat transfer capability than air, enabling stable cooling where rack power is very high. This makes statementAtrue. The combination ofCloud + AIpushes operators to reduce PUE and total energy cost through more intelligent control, higher efficiency cooling architectures, and integrated energy management, so statementBis also true. For large data centers, another clear trend is increasingchilled-water supply/return temperatures(higher inlet and outlet temperatures). Warmer water improves chiller efficiency, expands the number of hours that free cooling can be used, and reduces compressor work, soDis true. However,evaporative coolingis not universally the “main solution” for large data centers because it is climate- and water-condition dependent and is typically deployed as one option among multiple architectures rather than the dominant default everywhere. Therefore,Cis the incorrect statement.

Huawei’s ECC800-Pro supports PUE (Power Usage Effectiveness) management as part of its energy efficiency and green data center features. In practical O&M, different sites calculate PUE differently depending on metering topology, what loads are included (IT load only vs. auxiliary loads), and whether the site uses integrated modules (UPS, cooling, lighting, etc.) or external systems. To handle these real-world differences, the ECC800-Pro provides two PUE configuration approaches on the WebUI.“Standard”mode is used when the site’s metering points and calculation logic align with a predefined Huawei template, enabling rapid commissioning and consistent reporting.“User-defined”mode is used when the customer’s metering structure or management requirements differ—allowing engineers to select specific measurement points, define inclusion/exclusion rules, and tailor the calculation path so that displayed PUE matches the site’s accepted KPI definition. This dual-mode design ensures PUE is both standardized where possible and flexible where necessary, improving energy analysis accuracy and supporting optimization actions.

Compressor preheating is a protection mechanism used during first power-on (and after long power-off periods) to improve compressor reliability before allowing refrigeration startup. The preheating function warms the compressor oil and reduces refrigerant migration and oil dilution, which otherwise can lead to liquid refrigerant in the compressor crankcase. If the compressor starts when oil is diluted or when liquid refrigerant is present, it increases the risk of abnormal noise, poor lubrication, high mechanical stress, and even liquid strike, which can damage the compressor and shorten service life. For data center cooling equipment, where continuous reliability is essential, the commissioning logic treats preheating as a required prerequisite for safe compressor operation. Therefore, O&M practice does not recommend bypassing or manually shutting down compressor preheating just to accelerate commissioning. The correct approach is to keep the unit energized and allow the preheating period to complete, then proceed with commissioning steps (fans, cooling system tests, alarms, and control verification) under proper protection conditions.

The correct sequence prioritizeselectrical safety first, then mechanical disassembly. You mustconfirm the batteries are not discharging(Step 1) to avoid working under load. Next, the cabinet must be placed into a safe powered-down state byswitching off the battery circuit breaker and long-pressing the POWER ON/OFF button to power off the cabinet(Step 6). Only after the cabinet is safely powered down should you open up the working area byremoving the front covers of the faulty module and adjacent modules(Step 3). Then youturn off the ready switchon the battery management module (Step 2) to prevent the system from re-enabling the module unexpectedly during maintenance. After that, youloosen the securing bolts and pull out the battery management module about 10 cm(Step 5) to create operating space and ensure isolation for subsequent operations. With the cabinet safely stopped, you canremove the cables and copper barsconnected to the faulty module (Step 7), and finallyremove the baffle plate and pull out the faulty battery module(Step 4).

In Huawei NetEco statistical reporting, the query range is constrained by the report data retention policy and how summary data is stored. Forhourly statistics, the platform keeps a limited window of high-granularity data to balance storage consumption and performance. The hourly report retention is120 hours, which equals5 days. That is why hourly statistics queries are limited to5 days—beyond that window, hourly granularity is no longer retained in the report database for direct querying. For longer time horizons, NetEco relies on lower-granularity summaries (daily/weekly/monthly/yearly). Formonthly statistics, the platform supports long-term trend analysis and KPI tracking, and the maximum historical horizon aligns with the long-term statistics retention boundary used by NetEco reporting, which isup to 5 years. This design ensures fast query response, manageable database growth, and clear separation between short-term operational detail (hourly) and long-term management analysis (monthly/yearly).

This statement is incorrect because it combines two different frame configurations into one description. In the UPS5000-H family,cabinet composition depends on capacity. For theUPS5000-H-1200 kVA, the user manual’s exterior description shows asingle power cabinet plus a bypass cabinet, together with theMDU. In other words, 1200 kVA is not described as “two power cabinets + one bypass cabinet” in its standard cabinet topology. By contrast, theUPS5000-H-1600 kVAis a wider frame and its maintenance/structure description explicitly showsPower cabinet 1, Power cabinet 2, and a bypass cabinet, and the product documentation also includes component sections for items like thesurge protection boxandMDU. Because the 1200 kVA model does not match the “two power cabinets” description, the combined statement (covering both 1200 kVA and 1600 kVA) isfalse, even though the “two power cabinets + one bypass cabinet” part is valid for 1600 kVA.

Huawei’s scenario-based data center facility portfolio is organized around clearly defined solution families that map to typical deployment scenarios and site sizes. FusionModule500 and FusionModule2000 are smart modular data center solutions designed for standardized, fast deployment in equipment rooms and enterprise edge/branch scenarios.They integrate key subsystems such as power supply and distribution, cooling, monitoring, and optional fire protection into a modular architecture that reduces footprint and accelerates on-site delivery. Likewise, FusionDC1000 is Huawei’s prefabricated modular data center series, delivered as complete, factory-integrated modules that combine civil engineering elements with electromechanical infrastructure for rapid construction, predictable quality, and scalable expansion across different capacity tiers. In contrast, FusionDC800 is not used as a defined scenario-based solution name within Huawei’s mainstream data center facility solution lineup (where “FusionDC” offerings are represented by the FusionDC1000 series and “FusionModule” offerings by numbered FusionModule solutions). Therefore, FusionDC800 is the option that does not match Huawei’s scenario-based solution naming.

In a lithium battery cabinet, any exposed conductive part that is electrically connected to the DC power path can present shock and arc risk, especially when technicians are using tools in a narrow space. Thegeneral positive/negative terminalsare the cabinet-level high-energy connection points, and accidental contact or bridging with a metal object can cause severe DC arcing, burns, and equipment damage. Thebattery positive and negative terminalson individual modules are also hazardous because each module contributes to the total string voltage and fault current capability. In addition, theshort-circuit copper bar between battery modulesis a direct conductive link in the series/parallel connection; it can be energized and can create an instant short circuit if contacted by tools, jewelry, or loose hardware. Huawei maintenance safety practice therefore requires insulating covers, protective shields, and strict tool control to prevent exposed hands or metal objects from contactinganyof these areas. Protecting all listed points reduces electric shock risk, prevents arc flash/arc burn incidents, and avoids unintended cabinet trips or permanent damage to terminals and busbars.

In Huawei alarm management,masking rulesare used to control how alarms are handled and displayed during specific conditions, such as planned maintenance, commissioning, device replacement, or known temporary abnormalities. When a masking rule is applied, the system can change how an alarm is classified so that O&M staff can distinguish between alarms that require immediate action and alarms that are expected or should be excluded from operational statistics. Two key statuses that masking rules can assign areMaintenanceandInvalid.Maintenanceindicates the alarm is generated during an approved maintenance activity (for example, power-off tests, sensor rewiring, cooling maintenance), so it is treated as expected and does not trigger normal escalation logic.Invalidindicates the alarm is not considered effective for operational follow-up—commonly used when a point is confirmed to be non-applicable, temporarily disabled, or its triggering condition is not meaningful to current operations. By contrast,ValidandStandardrepresent normal alarm handling states rather than outcomes specifically “identified by masking rules.”

In Huawei data center facility equipment (such as precision cooling units and related controllers), alarm presentation follows a clear severity-based design so technicians can recognize urgency immediately without entering detailed menus. Acritical alarmrepresents the highest severity level and is treated as a condition that may impact safe operation, cooling continuity, or equipment protection. For this reason, the LCD controller uses the most prominent visual and audible indications: theindicator turns redto show critical severity, and thebuzzer sounds continuouslyto ensure the alarm cannot be overlooked in a noisy equipment-room environment. This behavior supports rapid response: O&M personnel can quickly identify that immediate action is required, then open the alarm list to locate the root cause, confirm whether the unit has derated or stopped, and execute the prescribed troubleshooting steps (for example, checking power status, sensor readings, fan/compressor status, water flow/pressure, and protection interlocks). Therefore, the statement correctly describes the standard critical-alarm indication method on the LCD controller.