Thermostart governor

During the nineteens some Zetor were equipped with a thermostart. A flame glowplug was mounted in the inlet manifold, fed with diesel from the lift pump via an electromagnetic valve, and all regulated by a thermostart governor (relay). This governor is connected to the valve, glow plug and indicator light.
Please can anybody explain in a pedagogical way the steps this governor takes and if possible, the different sequence times.

Hazze

Some 1970's TK Bedford Diesels had the same set up, you may have more luck finding info on them.
They were fitted to the Bedford 381ci Diesel, the 466ci Diesel and the 500ci Diesel.

I have a Bedford 381 with the remains of the thermostart system but has been disconnected long ago ...... does not get cold enough in NZ to need it
and i think they were prone to catching fire!