To better understand the SE8c you must first take into consideration that the device is divided into 8 elements of two inputs, one output for turnouts and 8 outputs for signal aspects. This arrangement is for organizational purposes.
Actually the SE8c is a multipurpose device designed to cover all of the basic needs of a security element that includes block occupancy of the element (via add on block occupancy device), routing within the element (via the control of a stall motor control of the turnout points), and the control of 8 output signals to the various aspects for the element.
With other add on devices (i.e. BDL168, DS64's, and PM42's) amazing things can be done in the way of signaling.
You are not restricted to using the inputs and outputs as arranged. You can mix and match as needed. Mixing and matching of inputs and outputs is possible. All you need to do is to be able to see a non standard application and make use of the various inputs and outputs of the SE8c.
You are only limited by your imagination of what you can do with the proper hardware and software.
As an example on my layout should a short occur on the rails for any reason all of the signals inside or leading to the affected non operational area automatically turn red. When the short is removed they return to their normal pattern. I use BDL168's to determine block occupancy, DS54's and DS64's to determine routing, PM42's to determine power to the rails, the PR3 for communication between the LocoNet and the computer (whose only function is to control the signaling system) and a old, no longer supported, computer program to handle the signaling system.
I have a second computer system, with its own PR3 to LocoNet connection, that functions as a dispatchers panel for those occasions when a dispatcher is part of the operating session.
As a side note you do not need to use the inputs of the SE8c if you do not want to nor do you have to use them for the intended reason. I do not use the SE8c turnout inputs or the turnout outputs at all. This does not mean I could not use them. It just means I do not care to use them. I do not use the block occupancy feature of the SE8c either. My preference is to use a device for its primary purpose. If there are secondary purposes I generally do not use them.
Experimentation is a very good source for information. I created a very small test layout many years ago for the purpose of experimentation. The dimensions is 30" x 48". The track plan is an oval with a passing siding and a spur. There are three turnouts controlled by Tortoises, 13 electrical blocks, 8 signal heads, 1 UP5, 1 PM42, 1 BDL168, 1 DS64, 1 SE8c, 1 PR3, a Zephyr, and an older computer running JMRI software.
Al
