Electrical Design Software | Elecdes Design Suite by Scada Systems Ltd

Power Numbers for Raceway, Cables and Wires

Power number description

The power number represents the power compatibility of a cable or wire when compared to other cables or wires. Sensitivity to electromagnetic interference is the usual use for the power number.

As a simple example, an instrument cable should have a different number from the power cable for a motor.

The power number informs the automatic routing functions of Paneldes which cables to keep separated from each other. Paneldes will only route conductors through raceway with the appropriate power number.

  • Each cable or wire has a single power number.

  • Each raceway segment can have one or more power numbers.

  • You can define the compatibility for each number 0...32768.

Power number "0"

The power number zero, "0", is a special number that disables the power separation feature of the automatic routing functions.

  • A cable or wire with power number "0" can be placed in ANY raceway segment.

  • A raceway segment with power number "0" can carry ANY cable or wire.

Incompatible power numbers

Although connected raceway segments may have different power numbers, if there is not at least one common power number between two raceway segments, then they cannot be connected together.

For example: a segment with power numbers "1-4, 9" can be connected to a segment with power numbers "3, 12" but not to a segment with power numbers "5-7,11".

Thus if two segments appear to be joined correctly in the model yet no route can be found through that junction, the segments may not have any common power numbers.

Point separated power numbers

Power numbers with different "point" values can be used on raceway segments in close proximity to prevent them from being connected together. A point value is added to a power number by adding a decimal point then fractional digits.

For example: "3.1" is power number "3" with point value "1".

The power number is the number before the dot. This is the number used when Paneldes checks if a cable can be carried by the raceway segment. However, when Paneldes is connecting segments, it will not connect two segments together if they have different point separated power numbers. A raceway segment with the same power number but no point separation can be connected.

For example: a segment with power number "3.1" can be connected to a segment with power number "3.1" or "3", but not to a segment with power number "3.2".

All of the segments in this example can carry a cable with power number "3".

This method can be used to prevent cross-connection between parallel runs of tray that have the same power number. If each run of tray has a different point separated power number, they can all carry the same cables, but they will not be cross connected between runs.

NEC signals power numbers

If you are using the NEC code to calculate raceway fill, you can set the power numbers that identify control or instrumentation (signals) cables and trays.

See How to Configure NEC Filling.

Power ranges for raceway

The power number for raceway segments can now contain one or more "ranges". This allows you to specify a range of power numbers that the tray can carry.

E.g. If you want a tray to carry all cables from 110 to 480, then enter the text "110-480" into the POWER number attribute of the tray segment.

NB: "1-5" is the same as "1,2,3,4,5"

A raceway segment can have several ranges separated by commas e.g. "110-480, 900-999, 5000-6000"

The power ranges for raceway segments can be set at insert time or with the Global Editor.

Split power numbers for tray

A raceway segment can, when necessary, be treated as 2 separate sides by "tray splitting".

Splitting only works on straight segments of tray.

To split a tray you must enter a complex POWER number setting when inserting or Global Editing the tray. This setting describes the POWER ranges and numbers on each side of the tray and the approximate split of the trays natural cable fill (CABLEFACTOR) capacity.


The text for a split tray is formatted as follows:

  • <power for side A> , <split data W.R.T side A> , <power for side B>

    e.g. "100-400, N0.6, 500-1000"

  • <power for side A> and <power for side B>

    These two parts describe the power ranges for each side just as a normal POWER setting does.

    In the example, side A can carry cables with power numbers in the range 100 to 400, side B can carry cables with power numbers in the range 500 to 1000.

  • <split data W.R.T. side A>

    Describes the split orientation and the proportion of the cable carrying capacity that is assigned to part A.

    In the example, "N0.6" specifies that side A is the NORTH SIDE (N/S/E/W can be used) and that side A comprises 60% (0.6) of the tray fill. NB: NORTH is +Y (WCS).

NOTE:

This feature should be used sparingly. Junction segments and corners can not be split and hence long routes with splits may become un-split or cause cables to cross over.

See also

Keeping power separated raceway on different layers

Panel ducting

Raceway

How to tune your model for wire and cable routing

Routing functions description

Route optimisation errors and warnings

Cable filling factor for raceway