Renogy RNG-KIT-STCS100D-VOY20 Connecting Manual

Connecting the Battery before Solar Panels to a Renogy Charge
Controller
When connecting to a Renogy charge controller it is likely you have seen a warning like the following:
WARNING! Connect the battery terminal wires to the charge controller FIRST, then connect the solar
panel(s) to the charge controller. NEVER connect solar panel to charge controller before the battery.
You might be asking yourself why? Or if there are any exceptions? The purpose of this article is to
answer those questions and shed light on connecting solar order of operations.
Why is this the rule?
Renogy charge controllers may turn on if they detect solar power (PV) or battery power. However, the
battery source defines the system voltage (for auto recognition), is a stable supply that allows
programming of the charge controller, and most importantly, is how the controller receives its operating
power to regulate solar power. Though a controller may turn on with PV input, the power source is
unstable, and in some cases can damage the charge controllers if they lack certain protections.
Wanderer 30 LI (Model: RNG-CTRL-WND30-LI)
In previous years, the protections did not apply to all charge controllers. Over the years, Renogy
controllers have improved on their electronic protections to the point where the controller would be
fine if PV is connected before battery power. If you find that you connected it in this fashion and the
controller is operating fine, then there is nothing to worry about. However, each controller may have a
different threshold for this protection so above all else, it is always good practice to connect the battery
first and then the solar panels to ensure system success and ability to program your controller.