Compass. The compass needle responds to currents carried by wires drawn across the compass. Only one compass can be placed. With the Select tool, you can move the compass and wire it to other objects. You attach wires to the compass's two nodes, which are indicated by the yellow rectangles in Figures 1 and 2.


Fig. 1


Fig. 2

By clicking on the icon below the compass (Figure 3), you can open up a panel (Figure 4) that allows you to change the number of wires wrapped around the compass. Increasing the number of wire increases the size of the Compass Deflection  


Fig. 3


Fig. 4

Double-clicking on the compass with Select depressed opens up a window titled Compass Deflection rather than a Properties Box. The window shows the face of the compass, with a blue & red compass needle.

This window shows the angular deflection of the compass needle due to current running through wires placed over the compass. By default, for a single wire looped across the compass, a standard current  produces a 3º deflection of the needle. Changing the number of wires changes the standard deflection to 5º for 2 wires, 7º for 4 wires, 9º for 8 wires, and 11º for 16 wires.

The standard compass deflection can be changed in the background properties, along with the standard current. However, only change the standard compass deflection if you do not intend to vary the number of wires. 

The direction of the compass deflection depends upon the current. If the electron current in entering the south, near end of the compass, the compass deflection is to the right and down (Figure 5). If the electron current enters the south, near end of the compass, the deflection is to the right and down. The Zoom In button increases the size of the Compass Deflection window.


Fig. 5