9.2 CNI4 Index Base
When the UMB index mount option is included with the instrument, a rotating magnet and two or three
magnetic sensor switches will be present inside the enclosure as seen below. For convenience, wires from
the sensor switches are prewired from the factory to the pulse counting input terminal block. In the
unlikely event that one of the two reed switches fails, the redundant input channel will continue to
register accurate counts.
The illustration below shows the CNI4 with the rotary magnet and magnetic sensor switches. For the sake
of clarity, this illustration does not show the routing of wires from the sensor switches.
Figure 9-2: Index Base with Magnetic Switches
Another option is the Uncorrected Pulse Output board, as seen below. This provides an additional dry-
signal pulse output that allows for connection to an external pulse counting instrument.
Figure 9-3: Pulse Output Board