Liquid Controls IT375 - Manual (Page 19)

Sponsler, Inc. Model IT375 Versions Pg. 19
6.3 RELAY AND 4-20mA OUTPUT VERSION
This version combines features of the DC powered with a 4-20mA output.
The 4-20mA output provides a two-wire retransmission of the flow rate. Both the 4mA and 20mA setpoints are fully
programmable so that the output can span either the entire operating range or only a portion.
The instrument draws its operating power from the 4-20mA loop and uses the internal lithium batteries for backup if the
4-20mA loop is interrupted. The alarm/pulse outputs are disabled if the 4-20mA loop is interrupted.
Specifications:
Resolution and Linearity: 0.05% of span.
Accuracy:
0.05% of span at 25°C.
0.1% (typ) of span, full temperature range.
Response (4-20mA): 0.5 second.
Loop Power Supply: 9-28 Volts.
Since the 4-20mA output is designed to provide power to the Model IT375, it is not isolated from the input. Hence, all
sensors must be self-powering (such as reed switches and coils). If external power is required to power the sensor (eg.
Namur switches, Hall effect sensors or opto-sensors), the power supply delivering the external power must be isolated
from the 4-20mA loop supply.
Typical Connection
Connection to a Sensor requiring External Power