Omega RD100B manual Measuring Input Section Delta Computation, Scaling, Square Root Computation

1.2 Measuring Input Section

•Delta Computation

The value obtained by subtracting the measured value of another channel (called the reference channel) from the input value of the channel set to delta computation is used as the measured value of that channel. The reference channel must be assigned to a channel whose channel number is less than that of the channel on which delta computation is specified. The channel on which delta computation is specified is automatically set to the same range type as the reference channel.

Channel set to delta computation

Input
		Measured value
value	–

Measured value on the reference channel

DC voltage

Note

A channel whose input type is set to DC voltage, TC, or RTD can be designated as a reference channel. However, channels set to scaling or square root computation cannot be designated.

•Scaling

The input values are scaled to values in the appropriate unit to be used as measured values.

Input value		Measured value
	10 V		300.0°C

0 V −100.0°C

•Square Root Computation

When the input type is DC voltage, the square root of the input value is calculated, the result is scaled to a value in the appropriate unit, and used as the measured value of the channel. Also, the low-cut function (input less than a given measured value is fixed to 0 (scale left value)) can be used.

	Channel set to square root computation
Input value			Scaling	Measured value
		√
			Measured value	Result of square
				root computation
			Low-cut value

Note

The square root computation on the recorder uses the following formula.

Fx = ( Fmax - Fmin )	Vx	- Vmin	+ Fmin
	Vmax	- Vmin

where Vmin (leftmost value of span) < Vmax (rightmost value of span)

Fmin (leftmost value of scale after scaling) < Fmax (rightmost value of scale after

scaling)

Vx is the input voltage and Fx is the scaled value

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Functional Description

1-3