what is the load relay used for??

[Ed ke6bnl]

I have a solar panel in my rv trailer and I have a panel on my shed to keep my two trucks charged that are use infrequently. the solar panel controller has a light for panel battery and load.. I do see that when I disconnect the panel the load light comes on and there is 12 v from the battery fed to the load leads. BUT WHAT PURPOSE DOES THAT SERVE. What is a practicle useage for this relay??

[Suprasoup]

More than likely your charge controller has a nightlight function. Most controllers that have this function use the PV input to determine day/night.

[Sunking]

To make you ask questions and pay more for something you will not use.

It is for a very low current device like a night light, so if the battery is over discharged, it will urn off the light. Just about completely useless and you paid extra for it. Goo dhigh quality controlers do not have them.

[Ed ke6bnl]

To make you ask questions and pay more for something you will not use.

It is for a very low current device like a night light, so if the battery is over discharged, it will urn off the light. Just about completely useless and you paid extra for it. Goo dhigh quality controlers do not have them.

I defentely did not pay much for the controller and as suprasoup says you could add a smalll led to this function as a night light and would indicate if the solar panel is not putting out in daytime

[Sunking]

night light and would indicate if the solar panel is not putting out in daytime

Hogwash.

Al the Load Terminal is a very small relay that connects the Battery to the Load Terminal. As long as the battery voltage is above 10.5 volts or not dead, the relay contacts connect the battery to the Load Terminal. If it has a Night Light function as you were told, would not be on during the day. So by your logic the panel would never work except at night.