..\Manuals\RCI-100-MDM rev.B.doc
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Inputs:
The RCI-100 has one dry contact input and one 0-20mA input. The dry contact
input is excited with 24VDC and will source approximately 20mA when the
contact is closed. A red LED lights up when the contact input is closed.
The analog input is configured as a 0-20mA input and has a 250
Ω
input
impedance. The input terminal has three connections: +24V, I/P, COM. The
+24V power output may be used to power field transmitters. Up to 500mA may
be used to power a transmitter. The input signal is connected to I/P(+) and
COM(-).
The analog input is connected to the RCI-800 in two fashions: 1) Normal (3-wire connection) or 2) two-
wire connection. On a 3-wire connected input, an external power supply or the +24V power output
terminal of the RCI provides power to the field transmitter. The field transmitter has a current source
that provides the 4-20mA signal back to the RCI-100. If using the power supply of the RCI-100, the
field transmitter may draw up to 125mA.
On a 2-wire connected input, the field transmitter receives power from the RCI-100 and superimposes
the signal onto the power return path. A maximum of 20mA will flow in such a connection. Make sure
to consult the field transmitter manual to determine how to connect it to the RCI-100.