The tortoise and the wabbit.

[OBJack]

Is anyone here familiar with the workings of a tortoise switch machine coupled to a Wabbit stationary decoder?

I am batting out of my league here and need some serious help please.

I have wired ( as per wabbit instruction booklet) some electro frog turnouts to enable auto throw to work.
The frog is isolated and is powered by the tortoise using connections 4 & 5.
Everything seemed to be going according to plan until I acquired a new loco whose pickup wheels all fitted neatly in the isolated frog area as it went thru the turnout.
As it did so, it stalled.
After much I found that the voltage across the frog went from 15v - 16v to about 2v as the all wheels made contact, hence the stall.
The other locos etc obviously had pick up wheels longer than the isolated frog and so did not stall, however the frog's voltage still dropped to 2 v as each set of pickup wheels of the trains passed over.

What have I done to cause this problemo.

If it is any help ( and not adding more confusion ).... When the train is stalled on the turnout if I give the isolated trigger rail a shot of DCC current by "un-isolating".... it then away we go.

Confused ?

I would certainly improve my sanity if someone could take the time to think this thru and come up with an answer for me please.


Jack