ISPSoft User Manual 10.2.5 Creating a Comparison Contact An example of a comparison contact in ISPSoft is shown below. > in the block represents a comparison type. S1 and S2 are objects which are compared. The data format which is accepted depends on the comparison type. Q can drive a coil or connect to a contact in series. The comparison contacts in a ladder diagram are similar to general contacts in that they can connect to other contacts in parallel or in series. A comparison contact can be inserted not only in one of the three ways described in section 10.2.4, but also by means of the following steps. (1) Click on the toolbar, and then select a type.
(2) Select a line, a contact, or a group of devices. Before users connect a comparison contact to a group of devices in parallel or in series, they have to draw a frame round the group of devices. After users make sure of the position in which a comparison contact will be inserted, they can click on the toolbar. 10-18