Kohler has two models of transfer switches that are a currently in production; the RDT and the RXT series. We won’t go over all of the differences, however the main difference would be the 4-wire start RXT vs the 2-wire start RDT. The RXT series is Kohler specific and only works with the newer RDC2/DC2 controller. The RDT series can work with any generator that is a 2-wire start because all of the intelligence is inside the transfer switch. We know that it can be a bit confusing so you can speak with any rep at AP and we can determine what would be the best option for your particular installation.
There are two kinds of switches that are common; a transfer switch with a load center and without. The difference in the two switches is the maximum load they can power. You would have to decide if you are backing up selected circuits, or if you are backing up your entire service before you know which type of switch you need. When you use a transfer switch with a load center it can help you to keep the cost of the generator itself down because you are picking only a couple of things to power. Since you are being selective you remove the risk of overloading the generator. Anything that has a high draw of electricity can simply be placed on a circuit that is not backed up.
The transfer switch without a load center can be considered a whole house transfer switch. As the name implies, you have the ability to power your entire service. You have to be a careful with this kind of switch and make sure that the generator can handle the entire power demand. If it can’t then you are putting your generator at risk to be overloaded. It may require working with your electrician to look into load-shedding some of the items with a large demand.
The last type of automatic transfer switch isn’t as common and would be considered a hybrid. It combines the functions of a load center switch and a whole house switch. You would want to consult with your electrician before purchasing an item like this, but, if you could make them work they are convenient since they save you space. This particular switch is typically for new construction or for homes with an abnormally large amount of circuits in the panel. This switch can be used in place of a transfer switch and main panel.