A2.2 input process section, A2.2.1 determining input value statuses, A2.2.2 converting the rate – Yokogawa EJX930A User Manual

Page 86: A2.2, A2.2.2, A2-2

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<Appendix 2. Integrator (IT) Block>

A2-2

IM 01C25T02-01E

A2.2 Input Process Section

When executed, the Integrator block first performs input processing in the order of:
"Determining input status" → "Converting Rate or Accum" → "Determining the input flow direction"
Switching between Convert Rate and Convert Accum is made using bit 0 (for IN_1) or bit 1 (for IN_2) of

INTEG_OPTS. INTEG_OPTS is one of the system parameters and should be set by the user. The values of

IN_1 and IN_2 are not retained if the power is turned OFF.

A2.2.1 Determining Input Value Statuses

The following shows the correlation between the statuses of input parameters (IN_1, IN_2) and the statuses of

input values used in the Integrator block.

Statuses of Input

Parameters (IN_1, IN_2)

Bit 4 of INTEG_OPTS

(Use Uncertain)

Bit 5* of INTEG_OPTS

(Use Bad)

Status of Input Values

Handled in IT Block

Good

Irrelevant

Irrelevant

Good

Bad

Irrelevant

H (=1)

Good

Bad

Irrelevant

L (=0)

Bad

Uncertain

H (=1)

Irrelevant

Good

Uncertain

L (=0)

Irrelevant

Bad

For addition (see A2.3), if the status of an input value is "Bad," the "Good" value just before the status changed

to "Bad" is used.

* Even if the Use Bad option is used, changing the internal status to "Good," the value of "Good" just before

the status changed to "Bad" is used.

A2.2.2 Converting the Rate

The following describes an example of rate conversion.
In rate conversion, firstly convert the unit of two inputs to that based on seconds.

Next, convert the unit of the inputs to the same unit to be added together. The unit of IN_2 is standardized to

that of IN_1. Then, calculates a weight, volume, or energy by multiplying each input value and block execution

time. Because unit information is not input to the Integrator block as an input value, the user must input in

advance tuned values to the TIME_UNIT1/2 and UNIT_CONV parameters.

TIME_UNIT1

second:÷1

minute:÷60

hour:÷3600

day:÷86400

input1

kg/hour

input2

lb/s

kg/s

kg

increment2

increment1

lb/minute

lb: pounds

Converts the unit into

that based on seconds

Standardizes the unit of

IN_2 to that of IN_1.

Because "lb/s" is converted into

"kg/s" in this example, the input

2 value is multiplied by 0.453.

(1 lb = 0.453 kg)

UNIT_CONV

x [conversion factor]

(Conversion factor:

0.453 in this example)

Converts the unit into

that based on seconds

TIME_UNIT2

second:÷1

minute:÷60

hour:÷3600

day:÷86400

kg/s

kg

× block execution time

× block execution time

FA0202.ai

Figure A2.2 Increment Calculation with Rate Input

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