Based on the Dell Power Calculator results showing 5.8A total draw, we can make some important calculations. Your 1800W UPS (PRP 3050 RM) has a VA rating of 2000VA, which gives us a power factor of 0.9 (1800W/2000VA).

// Sample calculation for power consumption in Watts
const amps = 5.8;
const volts = 230; // Standard European voltage
const powerFactor = 0.9;

const totalWatts = amps * volts * powerFactor;
console.log(Total power consumption: ${totalWatts.toFixed(2)}W);
// Output: Total power consumption: 1200.60W

Your UPS has 8.5Ah batteries. With two battery strings (typical for rackmount UPS), runtime can be estimated:

// Runtime estimation function
function calculateRuntime(batteryAh, batteryCount, loadWatts, efficiency = 0.85) {
  const totalWh = batteryAh * 12 * batteryCount; // 12V per battery
  const usableWh = totalWh * efficiency;
  return (usableWh / loadWatts) * 60; // Convert to minutes
}

const runtimeMinutes = calculateRuntime(8.5, 2, 1200);
console.log(Estimated runtime: ${runtimeMinutes.toFixed(2)} minutes);
// Output: Estimated runtime: 8.67 minutes

Your current 1200W load is safely within the 1800W limit (66% utilization). Best practice suggests keeping loads below 80% of rated capacity for optimal performance and battery life.

The "8.5Ah" rating refers to battery capacity, not load capacity. You can add more equipment until you reach:

• 1800W maximum continuous load
• 2000VA maximum apparent power

For servers with redundant PSUs (like your Dell units), each PSU typically shares the load. Here's how to model this:

// Redundant PSU calculation
class Server {
  constructor(maxWatts, psuCount, redundancy = true) {
    this.maxWatts = maxWatts;
    this.psuCount = psuCount;
    this.redundancy = redundancy;
  }
  
  get loadPerPsu() {
    return this.redundancy ? this.maxWatts / this.psuCount : this.maxWatts;
  }
}

const r610 = new Server(800, 2, true);
console.log(R610 PSU load: ${r610.loadPerPsu}W per PSU);
// Output: R610 PSU load: 400W per PSU

1. Implement power monitoring to track actual usage. Many UPS units provide SNMP or USB interfaces for this:

# Sample Python code to monitor UPS via NUT
import nut2

client = nut2.PyNUTClient()
print(client.list_vars("ups1"))

2. Consider future expansion - the 600W headroom allows for additional equipment but impacts runtime.

3. For critical loads, consider implementing graceful shutdown scripts when battery reaches 20% remaining.

Based on your rack configuration and Dell's power calculator, your current setup draws approximately 5.8A. Let's break down the power requirements for each device:

// Sample power calculation pseudocode
const devices = [
  { name: "Netgear 1100", watts: 150 }, // Estimated from similar NAS devices
  { name: "QNAP U-859 RP+", watts: 120 }, 
  { name: "Dell R610", watts: 800 }, // With dual PSUs (50% load each)
  { name: "Dell 1950", watts: 750 },
  { name: "Dell 2850", watts: 850 },
  { name: "Screen L1710S", watts: 25 }
];

function calculateTotalLoad(devices) {
  return devices.reduce((total, device) => total + device.watts, 0);
}

const totalWatts = calculateTotalLoad(devices);
console.log(Total power requirement: ${totalWatts}W);

Your PRP 3050 RM UPS has:

• 1800W maximum load capacity
• 8.5Ah battery capacity at 48V

The key formula to understand is:

Runtime (hours) = (Battery Ah × Battery Voltage × Efficiency) / Load (Watts)

Example calculation for your setup (assuming 90% efficiency):

const batteryAh = 8.5;
const batteryVoltage = 48;
const efficiency = 0.9;
const runtime = (batteryAh * batteryVoltage * efficiency) / totalWatts;

console.log(Estimated runtime: ${runtime.toFixed(2)} hours);

Since you have two UPS units with dual PSU servers, you need to ensure:

1. Each UPS can handle the full load if one fails (N+1 redundancy)
2. The runtime meets your requirements during outages

Here's how to check redundancy:

function checkRedundancy(upsWatts, totalLoad) {
  const singleUpsLoad = totalLoad / 2; // Assuming load balancing
  const redundancyPass = upsWatts >= totalLoad;
  
  return {
    normalOperation: singleUpsLoad <= upsWatts,
    redundancyScenario: redundancyPass,
    headroom: upsWatts - singleUpsLoad
  };
}

const redundancyCheck = checkRedundancy(1800, totalWatts);
console.log(redundancyCheck);

Based on your configuration:

• Monitor actual power draw using UPS management software
• Consider adding environmental sensors for temperature monitoring
• Implement automated shutdown scripts for critical servers

Sample shutdown script for Linux servers:

#!/bin/bash
# UPS monitoring and graceful shutdown script

MIN_RUNTIME=5 # minutes remaining before shutdown
POLL_INTERVAL=60 # seconds

while true; do
  remaining=$(upsc myups@localhost battery.runtime | awk '{print $1}')
  if [ $remaining -le $((MIN_RUNTIME * 60)) ]; then
    echo "Initiating shutdown sequence..."
    # Add server-specific shutdown commands
    ssh admin@dell-r610 "sudo shutdown -h +1"
    ssh admin@dell-1950 "sudo shutdown -h +1"
    exit 0
  fi
  sleep $POLL_INTERVAL
done