RDHx Test Guide (Via Rack Mounted Air-Cooled Load Banks)

1. Overview

2. Reference Standards & Scope

2.1 Industry Standards

• ASHRAE TC 9.9 (Data Center Cooling Standards)
• YD/T 4024-2022 (Data Center Liquid Cooling Technical Requirements)
• UL 62368-1 (Electrical Safety for Audio/Video, Information and Communication Technology Equipment)
• NFPA 110 (Emergency Power Systems)

2.2 Test Scope

• RDHx airflow resistance & heat dissipation efficiency
• Rack inlet/outlet temperature distribution
• HVAC compatibility & data center PUE baseline
• Structural integrity, safety, and alarm functionality
• Air-cooled vs. liquid-cooled performance comparison

3. Test Environment & Preparations

3.1 Environmental Conditions

• Ambient temperature: 22–26°C
• Relative humidity: 40%–60% (non-condensing)
• Atmospheric pressure: 86–106 kPa
• Temperature fluctuation: ≤±1°C

3.2 Air-Cooled Load Bank Specifications

• Power range: 10–50 kW (0–100% step adjustment)
• Voltage: 380V/400V 3-phase (50/60 Hz)
• Cooling method: Forced-air cooling (variable-speed fans)
• Airflow: 0.5–2.0 m³/s (per rack)
• Control: Local/remote monitoring (kW, temperature, airflow)

3.3 Instrumentation (Calibrated)

• Temperature sensors: ±0.1°C accuracy (inlet/outlet/ambient)
• Anemometer: ±2% FS (airflow velocity)
• Power analyzer: ±0.5% FS (kW, kVA, PF)
• Differential pressure gauge: ±1 Pa (cold/hot aisle pressure)
• IR camera: ±0.5°C (surface temperature distribution)

3.4 Pre-Test Checklist

1. RDHx physical inspection: No damage, secure mounting, intact seals
2. Load bank connection: Proper grounding, cable torque verified, no loose connections
3. Safety: Fire extinguisher (Class C), PPE (insulated gloves, face shield), clear ventilation
4. Liquid loop (if applicable): Isolation valves closed, no leakage, pressure 0.4–0.6 MPa

4. Core Test Items & Procedures

4.1 Baseline Air-Cooled Test (Without RDHx)

1. Install air-cooled load banks in the test rack (no RDHx mounted)
2. Set load bank to 10 kW/20 kW/30 kW/50 kW (steady state)
3. Record data every 5 mins for 30 mins per load:
   • Rack inlet temperature (cold aisle)
   • Rack outlet temperature (hot aisle)
   • Load bank airflow & power consumption
   • Ambient temperature & humidity
   • Cold/hot aisle differential pressure
   
   
4. Calculate baseline metrics:
   • Heat rejection to room: 100% of load bank power
   • Average outlet temperature: ≤35°C (HVAC design target)
   • Baseline PUE: Data center power / IT load
   
   

4.2 RDHx Airflow & Thermal Performance Test

1. Mount RDHx on the test rack rear; connect liquid loop (if open-loop test)
2. Set load bank to target loads (10/20/30/50 kW); RDHx liquid supply: 22°C, 0.5 MPa
3. Run steady state for 60 mins per load; record:
   • RDHx inlet/outlet air temperature
   • Liquid supply/return temperature & flow rate
   • Heat removed by RDHx: Q = m × c × ΔT (liquid side)
   • Residual heat to room: Load power – RDHx heat removal
   • RDHx surface temperature (IR camera scan)
   
   
4. Acceptance Criteria:
   • RDHx heat removal ≥ 80% of load bank power (at 22°C supply)
   • Rack outlet temperature ≤ 28°C (RDHx cooled)
   • Surface temperature uniformity: ≤5°C (no hot spots)
   
   

4.3 Airflow Resistance Test

1. Set load bank to 30 kW (constant); adjust RDHx fan speed (if active) or liquid flow (if passive)
2. Measure airflow at rack inlet/outlet with/without RDHx
3. Calculate airflow resistance: ΔP = P_inlet – P_outlet
4. Acceptance Criteria:
   • Airflow reduction ≤ 10% vs. no RDHx
   • ΔP ≤ 5 Pa (no excessive airflow restriction)
   
   

4.4 Transient Load Response Test

1. Start load bank at 10 kW; ramp to 50 kW within 10s (step change)
2. Record temperature, airflow, and liquid parameters every 1s for 5 mins
3. Acceptance Criteria:
   • RDHx stabilizes within 30s
   • No over-temperature alarm (>30°C)
   • Pressure fluctuation ≤ ±10%
   
   

4.5 Safety & Alarm Function Test

1. Over-temperature alarm: Simulate RDHx outlet air >30°C; verify alarm & load reduction
2. Liquid leakage alarm: Simulate minor leak; verify detection & valve shutdown
3. Power failure: Cut off RDHx power; verify load bank safety shutdown
4. Acceptance Criteria: All alarms trigger correctly; no safety hazards

4.6 Long-Term Stability Test

1. Set load bank to 80% rated power (40 kW); run for 500 hours
2. Monitor parameters daily: Temperature, airflow, pressure, leakage
3. Acceptance Criteria:
   • No performance degradation (≤5% heat removal drop)
   • No leakage or structural damage
   • All components operate normally
   
   

5. Data Analysis & Reporting

5.1 Key Metrics to Report

• Baseline vs. RDHx-cooled outlet temperature
• RDHx heat removal efficiency (%)
• Airflow resistance (Pa)
• PUE reduction (baseline vs. RDHx)
• Temperature uniformity (°C)
• Transient response time (s)

5.2 Test Report Template

1. Test Overview: Date, location, RDHx/load bank model, operator
2. Environmental Conditions: Temp, humidity, pressure
3. Test Data: Raw data tables, curves (temperature/time, airflow/load)
4. Performance Analysis: Comparison with baseline & design specs
5. Compliance: Pass/fail status for each test item
6. Recommendations: Optimization for airflow, liquid parameters, or maintenance

6. Advantages of Air-Cooled Load Banks for RDHx Testing

• Cost-effective: No liquid loop required; easy deployment
• Realistic simulation: Replicates traditional server hot exhaust
• Baseline comparison: Enables direct air-cooled vs. liquid-cooled performance 对比
• Flexible testing: Suitable for pre-installation, on-site, and temporary test environments

7. Safety Precautions

• Always perform lockout/tagout (LOTO) during electrical connections
• Maintain a minimum 1m clearance around load banks for ventilation
• Avoid contact with hot surfaces (RDHx/load bank) during operation
• Stop the test immediately if abnormal noise, smoke, or leakage occurs