PDN schematics overview

Power Distribution Network (PDN) schematics are included on consoles to provide an overview of available power sources and to allow for the configuration of those sources. Power sources and vessel systems connected to them are all represented on the PDN as nodes. Nodes are connected by conduits which are shown on schematics to provide an overview of available distribution pathways for power.

PDN schematics on consoles have a canvas mode which allows them to be drawn or edited. 



Distribution nodes are the most common. They receive power from other nodes upstream from them and make power available (usually converted to a new power standard) to nodes downstream from them.

A node receives power via its upstream interface and supplies power via its downstream interface.


Power is delivered between nodes by conduits. A node connects to a conduit from either its upstream or downstream interface via a conduit tap. Connection to a conduit provides access to any other node also connected to that conduit via a complementary interface. For example, a node connected via an upstream interface tap will be able to receive power from any node with a downstream interface tap to the same conduit.


Schematic denotation is designed to provide information as clearly and quickly as possible.

Node Symbols

Nodes are represented by two types of symbol. The symbol for supply or distribution node is a rectangle enclosing data regarding the node’s designation, rating and current status. The wider vertical line to one side of the symbol represents the node’s upstream interface.

Touching a distribution node symbol provides access that node’s monitoring and control interface.

The symbol for a consumption node (a vessel system, usually one of the systems being controlled by the console the schematic is displayed on) displays only system designation information and is distinguished by its extra wide upstream interface.

To facilitate different schematic layouts, the node symbols are reversible. The upstream interface is always represented by the wider vertical line regardless of which side of the symbol it is on.

Consumption nodes are not touch activated – their control and monitoring interfaces will already be available on the console (or another console if an outer node – see below).

Conduit Symbols

Conduits are represented by coloured horizontal or vertical lines, with a different colour representing each distinct conduit. A conduit tap (connecting to a node) is represented by an angled line which ‘flows’ in the direction of power delivery. For example, a conduit tap to a node’s interface will always meet the node symbol at a point vertically lower than it meets the connecting conduit.

Conduits are also accompanied by a control symbol, which displays designation, rating and status information. The conduit control symbol is similar to a node symbol except that the nodes wider upstream line is replaced by two adjacent parallel lines.

Touching a conduit control symbol provides access that conduit’s monitoring and control interface.

Conduit Tap Orientation

Conduit taps may have different orientations in the schematic to support required layouts. Conduit taps may be oriented horizontally where a horizontal schematic flow is required.

Alternatively, conduit taps may be oriented vertically where a vertical schematic flow is required.

Inner and Outer Schematics

A PDN schematic will typically show at least the conduits connected to the systems being controlled or monitored by the console, and any upstream nodes available on those conduits. These directly connected nodes form the inner schematic. Conduits directly connected to console systems are inner conduits. Upstream nodes connected to those conduits are inner nodes.

To provide greater context the schematic may also show conduits and nodes connected upstream from the inner nodes. This additional level of information forms the outer schematic. Conduits connected upstream of inner nodes are outer conduits. Upstream nodes connected to those conduits are outer nodes.

Additionally, the schematic may show other nodes also connected to the inner conduits via their upstream interfaces (including other systems not controlled by the console). These nodes are also outer nodes.