when a right diverging tunout is not

I was looking at a site giving advice for model railroad switches etc, specifically left and right hand turnouts. In most cases, the mainline track is the one going straight though the turnout and the other track is the one diverging, left or right as the case may be and for curved turnouts, the track that continues with the same radius is the main and the diverging track follows a tighter radius.

But what if the mainline track is the one that diverges and the straight through track is the secondary line? Does a right diverging turnout become a left diverging one, with the appropriate changes in signals?

Here the mainline curves to the right and the secondary track continues on straight for a while.

To my way of thinking, two factors are important here.

1. In most systems the signalling is set for through trains running on the main line, so your statement "the mainline curves to the right and the secondary track continues on straight" would hold true and the left diverge would have to be signalled as the diverging track, allowing for point 2 below.

2. The curve to the right must be rated as a "line speed" curve with no speed reduction. If not then it *could* be considered as a diverging track and require appropriate signalling at a caution level.

My opinion.

Your mainline track isn't diverging, it's just has a curve.

Since the tracks to the left are a siding off the main, you signal as left diverge. The fact that the siding goes straight in line with the main leading up to it changes nothing.

An operational solution to this is to use: "TRI switch indicator" KUID:481384:11210059 Install it ahead of the switch, open the help menu and configure it: Green for the side you want it to be mainline, orange for the diverging side. It does not matter if the tracks are curved or straight. Note, the orange side will limit the speed, leaving the green side to whatever the main line is set. I have been using it for quite some time and it works.