Part of charging cable 20F warmer

[alsetyledom280]

I have a chargepoint home flex charger for less than 2 months old. It is perfect. However I noticed that under 48amp charging, part of cable (the section right above LED) is quite warm (90F) vs rest of cable (60F to 70F range). I would not understand the physics here except a guess that particular section has more resistance (hence heat) due to cable management position. My 48amp charging looks normal to me at votage of 238v.

 

[VT_EE]

per chatgpt, have fun.

Q1: I have an EE related question, why would coiled electrical cable under load (say continuous 48amp) generate more heat than flat cord?

A1: The amount of heat generated by an electrical cable under load depends on several factors such as the current flowing through the cable, the resistance of the cable, and the thermal conductivity of the cable's material.

When a cable is coiled, the individual turns of the coil are closer together, and the cable's cross-sectional area is effectively reduced. This can increase the resistance of the cable, which means that more energy will be dissipated as heat as the current flows through the cable.

In contrast, a flat cord has a larger cross-sectional area, which can lower its resistance and reduce the amount of heat generated under the same load as compared to a coiled cable.

Furthermore, the coiled cable has a lower surface area exposed to the air, which can limit its ability to dissipate heat through convection, whereas the flat cord has a larger surface area exposed to the air, which can enhance its heat dissipation.

Therefore, the combination of increased resistance and reduced surface area for heat dissipation can lead to a higher temperature in the coiled cable than the flat cord under the same load.

Q2: if the wires inside the cord has 2 hot and 1 ground (240v setup, 48amp), will coiled cord get more electro-magnetic effect somehow?

A2: A coiled electrical cable carrying a 240V, 48A current will generate an electromagnetic field (EMF) due to the flow of the electrical current. The EMF generated will be proportional to the current flowing through the cable and the geometry of the cable.

When a cable is coiled, the turns of the coil are closer together, and this can increase the strength of the magnetic field generated by the cable. This is because the magnetic fields generated by each turn of the coil add up, resulting in a stronger overall field.

However, the impact of the coiled cable's geometry on the EMF is usually small compared to the impact of the current flowing through the cable. Therefore, any increase in the EMF due to coiling the cable is likely to be negligible compared to the overall EMF generated by the cable carrying a 240V, 48A current.

It is worth noting that if the coiled cable is positioned near sensitive electronic equipment or other devices that are susceptible to electromagnetic interference (EMI), the stronger EMF generated by the coiled cable may cause interference with these devices. In such cases, it is recommended to use shielded cables or take other measures to reduce the EMI.

Are those really ChatGTP responses? If so, that is incredible.

 

[alsetyledom280]

Are those really ChatGTP responses? If so, that is incredible.

Yes sir it is

 

[VT_EE]

Yes sir it is

Damn!

 

[thefisch]

Adding some data points I took this morning for charger temps. Mine is a Gen2 WC that's been running at 48amps for 3 hours (10-50%) since 7am in enclosed garage.
Garage - 80F (welcome to Florida)
Breaker 60A - 110-115F
Conduit - 90-95F
Charger - 110-115F
Cable - 90-100F
Handle - 100F

 

[alsetyledom280]

This is very helpful and thanks for the data collection. My garage is 65F this morning and cable is about 80F to 90F under 48amp for 2h. Breaker is about 75F