08/11/2026
Melted End??? The Most Common Causes & How To Prevent
Most melted ends (male or female plugs) are NOT caused by surges and spikes. While these are high voltage transients (could be hundreds or even thousands of volts), they happen way too fast (billionths and thousands of a second) to heat up and melt metal or plastic.
Typically melted ends are a drawn out slow process that can take many minutes to hours. So what causes this?
Resistance = Heat. If electrons can freely and easily move through copper wire or brass conductors they do not bounce into each other as much. If you have points of resistance, think bad/loose connection, oxidized/corroded metal, pitted or tarnished metal, you have a resistance layer. The electrons have to 'work harder' to get through, they bump into eachother and cause heat. Like a toaster ovens heating elements, the resistance causes the wire/metal to heat up. As it heats up, it becomes more resistive and you have a thermal runaway effect, resistance causes heat, heat causes resistance and eventually something fails.
Gaps or bad female ends can cause arcing. Those little blue sparks you see is plasma, yes, like lightning and it is hot. This causes heat, and/or it can pit/vaporize the metal conductors. Pitted/burned metal conductors cannot conduct electricity as well as a nice shiny blade of copper/brass and you have resistance.
Low voltage causes inductive loads (AC compressor, fans, electric motors) to draw more amps. More amps (amperage) is the volume/flow of electrons through the wire. More electrons means more bumping and bouncing into eachother which can cause heat. (heat = resistance).
Even high ambient temperature can exascerbate the situation, as you have a jump on higher temps. This also typically means you have the AC running to cool down and you have a higher amperage draw.
Conclusion:
- Try to keep amp draw as low as possible. If you do need to use power, think about periods where you can let wires/conductors/plugs/outlets 'cool down' for 10-20 mins.
- Make sure all connections are tight and secure, check periodically for oxidized, corroded, pitted, or loose connections. Fix as needed.
- Try to make sure you have proper voltage. Inductive loads (your RV's biggest loads) will draw more amps when voltage is low. If you are using power for long periods of time (2-3 hours or more), ensure that you are keeping amp draw to about 80% of the max. For 50A this means forty amps, for 30A this means twenty four amps.
Using a Power Watchdog surge protector allows you to see in real time your volts, watts, and amps. The EPO (emergency power off) units will shut down if you are drawing too many amps (over current). In addition to protecting you from surges and spikes.
Stay Protected With The Best!
Introducing Watchdog Power Center The End-All, Be-All of RV Power Protection Learn More Shop Voltage Boosters Shop Surge Protectors Shop Smart Inlets Featured Products Watchdog Powercenter - 30 Amp $819.99 Out of Stock Watchdog Powercenter - 50 Amp $1,199.99 LEARN MORE Stay on Guard Join the Watchdo...