Safety gate
Hot, smoking, melting, sparking, or burning-smell means stop use.
CPSC warns that extension cords can overheat when overloaded or damaged and that hot plugs/sockets can be associated with deteriorated connections. If there is smoke, active arcing, melting, or a fire hazard, disconnect power only if it can be done safely and use emergency services as appropriate.
Step 01
Calculate what the cord is actually carrying.
Use equipment labels or power-supply ratings to estimate the maximum simultaneous load and compare it with the extension cord’s marked amp/watt rating. Do not assume a cord is adequate because the connected devices normally draw less than their adapter’s maximum.
If a device manual says it should not be used on an extension cord, follow the appliance manufacturer’s instruction.
Step 02
Use the heat location as a clue, not proof.
Load, wire gauge/length, damage, or bundled/covered routing can contribute.
A loose or resistive connection becomes more concerning. Inspect both mating parts.
Stop using that receptacle for the setup and have the building wiring/receptacle evaluated.
Step 03
Check routing and physical condition.
Do not run the cord under rugs or where furniture, doors, chair casters, or cable-management hardware crushes it. Do not coil or cover a heavily loaded cord in a way that traps heat. Replace cords with cut, cracked, abraded, melted, or loose components.
Decision
What fixes the problem?
Reduce the load or use an appropriate permanent circuit/receptacle arrangement.
Replace it with a listed cord whose rating and environment match the intended temporary use.
Stop using that outlet and involve a qualified electrician.
Related
Sources