SAE connector
The SAE connector is a physically self-mating hermaphrodite two-conductor DC connector commonly used for solar and automotive applications (also motorcycles). It is so named for the Society of Automotive Engineers who created the specifications this connector is based on.
Although the plug is physically hermaphroditic, and any SAE connector can be connected to any other SAE connector, they are NOT electrically hermaphroditic and care needs to be taken to maintain correct polarity when connecting different plugs to each other.
Although there is a risk of short-circuiting a battery charger, the risk is minimal and often mitigated by the circuitry of the battery charger itself. On the other hand, the short-circuit current of the lead–acid batteries installed in vehicles is sufficiently great, that a short circuit could result in a fire or explosion. The priority is therefore given to avoiding short circuits of the vehicle battery, rather than of the charger.
Although the term “SAE connector” is commonly used to refer to the pictured two-pin connector, there are many different connector standards designated by SAE International that may also be referred to by this term. Furthermore, while the design of the subject connector was inspired by and based on SAE Standards, the connector itself has no official SAE designation.
Certainly, the SAE perspective was toward automotive applications, including: trailer hitch/lighting wiring, onboard mechanisms (such as power windows), and ect.
Powerpole connectors
Powerpole connectors are a series of connectors developed by Anderson Power Products[9] and are available in a variety of sizes and colors. The commonly used 15/30/45 series connectors are interoperable with each other and use the same housings but use different contacts for different wire sizes and current requirements.
Powerpole connectors are physically and electrically genderless, thus avoiding the need to worry about which end is the plug and which the socket, or which end has the correct polarity, as is the case with the physically but not electrically genderless two-wire trailer plug.
Solar Connector
Solar connectors are common on photovoltaic panels. Because these panels are exposed to the weather for decades, Solar connector (Male) includes a rubber sealing ring to keep out moisture. Because solar panels are often stacked in strings of hundreds of volts, Solar connector has locking clips to hold the wires together. Because solar panels can be connected in series strings, or parallel arrays, the positive and negative terminals use separate connectors.