PiterEthnoExp. Part II. Inside a Drawbridge

October 27 ... November 19, 2013

Let’s go see how a drawbridge works.

All it takes to open the bridge is a few button pushes.

Hydraulic System Parameters
Pump Motors: Pump 1, Pump 2
Pump Hydraulic Valves: Pump 1, Pump 2
Close Bridge. Bell. Stop.

Everything is controlled by a computer, which has two programs installed on it: Trinity Bridge and Solitaire.

Poke, poke.

Locking Mechanisms, Pump Motors: Pump 5, Pump 7
Hydraulic Valves for Locks: Pump 5, Pump 7
Wedge, Pump Motors: Pump 6, Pump 8
Hydraulic Valves for Wedges: Pump 6, Pump 8
Motor Controls, 1st Circuit, 2nd Circuit: On/Off
Open/Stop/Close

A cozy corner.

Underneath the bridge is a giant space where the counterweight goes.

The huge concrete thing on the ceiling is the counterweight. Up until the mid-1960s, the bridge span swung 90 degrees to the side to open the bridge. Now it swings the way tourists like: straight up.

If something breaks, there’s always a screwdriver handy to fix it.

All right, it’s time to open the bridge.

Here we go.

The counterweight is fully lowered.

Yeah, baby!

No enemies on the horizon.

Camera 12: Signal lost

Ships are a go.

It’s an incredible invention, to be sure.