Omega RD100B manual Measuring Input Section

1.2 Measuring Input Section

Input Section

Number of Measurement Channels and Scan Interval

The recorder samples the input signals on the measurement channels at the scan

interval to obtain the measured values.

Model	Number of Channels	Scan Interval
1-pen model	1	125 ms
2-pen model	2	125 ms
3-pen model	3	125 ms
4-pen model	4	125 ms
Dot model	6	1 s
		(However, the scan interval is 2.5 s when the
		integration time of the A/D converter is 100 ms.)

Input Type, Measurable Range, and Computation

The recorder can measure the following types of inputs.

Input Type	Measurable Range
DC voltage	DC voltage in the range of ±20 mV to ± 50 V
1-5V	See “1-5V” below.
Thermocouple	Temperature range corresponding to each type: R, S, B, K, E, J, T, N, W, L, U,
	and WRe
RTD	Temperature range corresponding to each type: Pt100Ω and JPt100Ω
ON/OFF input	Contact input: Open contact is OFF (0). Closed contact is ON (1).
	Voltage input: Less than 2.4 V is OFF (0). Greater than or equal to 2.4 V is ON (1)

•1-5V

1-5V is scaled to values in the appropriate unit to be used as measured values. Also, the low-cut function (input less than 0% is fixed to 0 (scale left value)) can be used.

•Current Input

A shunt resistor is attached to the input terminal. The current signal is converted to a voltage signal and measured. The measurable range is the range equivalent to the

“DC voltage” range indicated above after converting the current to the voltage signal.

Note

Three types of shunt resistors (250 Ω, 100 Ω, and 10 Ω) are available for current input (see “Optional Accessories (Sold Separately)” on page v). For example, a 250-Ωshunt resistor is used to convert the signal to the range of 1 to 5 V for 4 to 20 mA input.

•Range Type, Measurable Range, and Recording Span

Various “range type” are available for the different types of inputs (for example thermocouple R). Each range type has a preset measurable range (0.0 to 1760.0°C for thermocouple R). Measurement can be made by specifying an arbitrary range within the measurable range as the input range. The measured values in the input range are recorded on the chart paper. The range of measured values that are recorded is called the recording span.

Measurable range
(Thermocouple R example)		Input range or
	1760.0°C	recording span
			1500.0°C (rightmost value of span)
			300.0°C (leftmost value of span)
	0.0°C

<Related Topics>

Setting the input range: Section 5.1

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