Replacing three-wire timed switch with a microcontroller

Question

The building is surrounded by 6 lights and 4 buttons, 3 of which are illuminated.

Right now the circuit is managed by a Perry 1IT 1051. Here are the official schematics:

While I'm happy with the basic functionality offered by the product, I would like to make the circuit "smarter":

1. Keeping a button pressed for a few seconds should turn on/off the lights without the timer.
2. Pressing a button shortly when the lights are turned on should (re)start the timer.

Programming the functions on a microcontroller such as ESP8266 is not an issue.

My question is: how should I connect the device without changing the existing wiring?

Answer 1

The Perry 1IT 1051 has three terminals for the following connections:

1. Terminal # 1 for 230 V ~ utility power

2. Terminal # 2 for 230 V ~ to the lamps

3. Terminal # 3 that is to be momentarily connected to neutral through one of the push button switches.

The existing wiring need not be changed provided that:

1. One of the controller outputs energises a relay, with 16 A - 250 V AC contacts, to turn on the lamps.

2. One of the controller inputs is energised through a relay, actuated by a momentary push button switch, in the 230 V AC circuit.