Omega CNI16 - Manual (Page 16)

This device may have a programmable communication output. The
RS-232 and RS-485 Output Connection are shown below.
External RS-232 connections are not available with -EI or C4EI options.
Figure 2.11
a) RS-232 Output Wiring Hookup b) RS-485 Output Wiring Hookup
This device may also have an
excitation output.
If the Dual Display model has a Low
Voltage power supply option, then
excitation is not available.
Excitation is not available if
communication option is installed.
Figure 2.12 Excitation Output
This device has snubber circuits
designed to protect the contacts of the
mechanical relays when it switches to
inductive loads (i.e. solenoids, relays).
These snubbers are internally
connected between the Common (C)
and Normally Open (NO) relay contacts
of Output 1 and Output 2.
If you have an inductive load
connected between Common (C) and
Normally Closed (NC) contacts of the
mechanical relays and you want to
protect them from the rush current
during the switching period, you have
to connect an external snubber circuit
between Common (C) and Normally
Closed (NC) contacts as indicated in
Figure 2.13.
12
Figure 2.13
Snubber Circuits Wiring
Hookup