Yokogawa 202 Field Mounting Rate Totalizer User Manual
Page 28

Versions
24
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 points are fully programmable so that the output can span across
the entire operating range or, alternatively, across a small section of the operating
range.
The instrument draws its operating power from the 4-20mA loop and uses lithium
batteries for backup if the 4-20mA loop is interrupted. The alarm/pulse outputs
are not supported if the 4-20mA loop is interrupted.
Specification
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 202D, 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.