The standard CAT5 cable is typically rated for temperatures between -20°C to 60°C (-4°F to 140°F). You can verify this by checking the cable jacket for markings like "CM" (communications cable) followed by temperature ratings. Common inscriptions include:

// Example cable marking interpretation
const cableMarkings = "ETL Verified CM 24AWG 60°C 300V";
const maxTemp = cableMarkings.match(/(\d+)°C/)[1];
console.log(Maximum operating temperature: ${maxTemp}°C);

When CAT5 cables exceed their rated temperature:

• Signal attenuation increases by approximately 0.4% per °C above 20°C
• Crosstalk between pairs worsens due to dielectric changes
• Permanent damage occurs above 60°C (conductor insulation breakdown)

For your radiator scenario, consider this Python simulation of thermal effects:

def calculate_signal_loss(base_temp, ambient_temp, cable_length):
    temp_diff = ambient_temp - base_temp
    loss_factor = 1 + (0.004 * temp_diff)
    effective_length = cable_length * loss_factor
    return min(effective_length, 100)  # CAT5 max length
    
print(f"Effective cable length at 70°C: {calculate_signal_loss(20, 70, 50)} meters")

Instead of routing along the radiator pipe:

1. Use plenum-rated CAT6A: Rated up to 75°C with better shielding
2. Install thermal insulation: Fiberglass sleeves can reduce heat transfer
3. Alternative routing: Consider ceiling drops or baseboard channels

For network admins needing to monitor such installations:

// Bash script to check for packet loss increases
#!/bin/bash
BASE_LOSS=$(ping -c 100 gateway | grep 'loss' | awk '{print $6}')
while true; do
    CURRENT_LOSS=$(ping -c 10 gateway | grep 'loss' | awk '{print $6}')
    if [ "$CURRENT_LOSS" -gt "$((BASE_LOSS + 5))" ]; then
        echo "WARNING: Increased packet loss detected - check cable conditions"
        break
    fi
    sleep 300
done

If temporary installation is unavoidable:

• Keep cable contact with pipe to under 30 minutes during heating cycles
• Use zip ties loosely to allow air circulation
• Monitor connection quality with:

# Continuous speed test logging
for i in {1..12}; do
    speedtest-cli --simple >> /var/log/thermal_impact.log
    sleep 3600
done

The standard CAT5 cable typically has a temperature rating between -20°C to 60°C (-4°F to 140°F). This information is usually printed directly on the cable jacket, marked as "CM/CMR/CMP" for general/riser/plenum ratings followed by temperature specifications. For example:

CABLE CAT5E 350MHz 24AWG CM 75°C (167°F) ETL VERIFIED

Cast iron radiators typically operate at 70-80°C (158-176°F) surface temperature, which exceeds most CAT5 cables' rated maximum. This creates three potential issues:

• PVC jacket degradation over time
• Increased signal attenuation (approx. 0.2% per °C above rated temp)
• Possible impedance changes (nominal 100Ω at room temp)

To monitor thermal effects programmatically, you can use Python with network tools:

import subprocess
import time

def test_connection_stability(host="8.8.8.8", count=100):
    cmd = f"ping -c {count} {host}"
    output = subprocess.getoutput(cmd)
    packet_loss = float(output.split('packet loss')[0].split('%')[-1])
    avg_latency = float(output.split('min/avg/max/mdev = ')[1].split('/')[1])
    return packet_loss, avg_latency

# Before heating test
normal_loss, normal_latency = test_connection_stability()
print(f"Baseline: {normal_loss}% loss, {normal_latency}ms latency")

# Simulate heat exposure (run when pipe is hot)
heated_loss, heated_latency = test_connection_stability()
print(f"Heated: {heated_loss}% loss, {heated_latency}ms latency")

For environments with heat exposure, consider:

1. High-temp rated cables: Look for "CMX-Outdoor" rated cables (-40°C to 75°C) or industrial Ethernet cables (-40°C to 85°C)
2. Conduit separation: Use metal conduit as heat shield with minimum 2" air gap
3. Fiber optic alternative: Media converters with OM3 fiber (rated to 85°C)

Implement automatic failover if temperature exceeds thresholds:

import RPi.GPIO as GPIO
import smbus
import os

# Setup I2C temperature sensor
bus = smbus.SMBus(1)
address = 0x48

def read_temp():
    raw = bus.read_word_data(address, 0) & 0xFFFF
    return (raw / 32.0) * 0.125

def network_failover():
    os.system("nmcli con up wifi-hotspot")
    os.system("iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE")

GPIO.setmode(GPIO.BCM)
GPIO.setup(17, GPIO.OUT) # Cooling fan control

try:
    while True:
        temp = read_temp()
        if temp > 60: # 60°C threshold
            GPIO.output(17, True)
            if temp > 70:
                network_failover()
        else:
            GPIO.output(17, False)
        time.sleep(10)
finally:
    GPIO.cleanup()