Specifications

181
Transducers
Glossary of Terms
Fixed-load output
An output system that can be used only with the load
resistance value connected to the output being a single,
predetermined value and with which an error occurs if the
load resistance value differs from the specified value.
Constant-voltage output/Constant-current output
An output system that can be used if the load resistance
value connected to the output is within a predefined range,
and is suited for cases where the load resistance value is
unspecified and cases where future load increase is
predicted.
Load
The full load resistance value connected to the output
terminals of a transducer.
Accuracy (grade)
A term expressing the accuracy of a transducer classified
according to the tolerance and limits of influence
(influence of temperature, influence of frequency and
other allowable limits of performance).
Example: The tolerance of a grade 0.5 transducer is within ±0.5%.
The tolerance for an input of 1000W and output of 5V is:
5V✕(±0.5%)=±25mV.
Output ripple (P-P)
An AC component contained in the output expressed by a ratio
of the peak-to-peak value of the AC component and the span.
Response time
The time it takes for the output to settle within a specified
range of a final stationary value when the input changes
suddenly from one fixed value to another.
Ordinarily refers to the time it takes for the output to settle within
±1% of the rated output value centered at a final output value
when a step input that gives rise to an output change of from 0%
to approximately 90% of the effective output range or from 100%
to approximately 10% of the effective output range is applied.
Effective output range
A range within the output range in which predefined
performance is guaranteed.
The diagram to the left is an
input-output characteristics
diagram for T-51KSS and T-
51HSS. The effective output
range is 0~0.8mA (the output
range of 0.8~1mA is not an
effective output range).
Saturation output
Although the output in the range 0~0.8mA is proportional to the input in
the diagram above, the proportion of change of output gradually
decreases and saturates with respect to the proportion of change of input
in the 0.8~1mA region. Such an output is called “saturation output”.
Output span
The difference between the upper-limit value and lower-
limit value of an effective output range.
Example 1: For an output of 5V, the span is 5V.
Example 2: For an output of 4~20mA, the span is 16mA.
Example 3: For an output of -5~0~5V, the span refers respectively to the +
side span of +5V and the – side span of -5V.
Auxiliary power supply (control power supply)
An AC power supply or DC power supply necessary for
operation of the transducer and supplied from the exterior
(i.e., not supplied from the measured circuit). If the
voltage of the measured circuit is comparatively stable, it
can be used for connection to the auxiliary power-supply
terminals.
Example: Connection to auxiliary power supply from a measured circuit.
Output
Load: 250Ω
Lead wire: 10Ω
Transducer
Load resistance value=10+250+250=510Ω
Load: 250Ω
Example
AC component
DC component (span)
Peak-to-peak value
Response time
1% of rated
output value
Output
0
0
Time
Final output value
Example
approximately 1
DC input
AC input
Effective
output range
mA
0.8
0.4
0
0
0
2.5
0.5
5
1
15
A
3
Input voltage terminals
Input
Source
(Voltage of
measured circuit)
Auxiliary power supply terminals