Honeywell VRX180 user manual Math Prompts, Input a Input H

Programming Function Blocks and Features

Math

Performs math on up to 8 inputs using a single operator. Output is CVn OV. Division by 0 is indicated by CVn OV’s displayed value flashing 0.

Table 4-22 describes the Math prompts. See Table 4-2 for additional prompts.

Table 4-22 Math Prompts

Prompt		Range/Selections	Definition
INPUT A - INPUT H	OFF, analog parameter,		Enter up to 8 input sources.
		number.	If connecting to an upstream loop, that loop output (LP# OV)
			MUST be INPUT A (see Feedback).
OUTPUT LOW LIMIT		Enter limits	Displayed output value will be clamped and will flash when
			these limits are exceeded.
OUTPUT HIGH LIMIT
OPERATOR		ADD, SUBT, MULT, DIV,	1. Input A OPERATOR Input B OPERATOR...Input H
		ABSVAL, SQRT and	where OPERATOR is one of these:
		STDDEV.
			add, subtract, multiply, or standard deviation
			(Standard Deviation uses all inputs.)
			Example: Input A minus Input B minus ...Input H.
			2. OPERATOR Input A
			where OPERATOR is absolute value or square
			root.
			3. Input A OPERATOR Input B
			where OPERATOR is divide.
			Note: Inputs 3-8 are not used in division.
FEEDBACK		OFF, analog parameter,	Select LP# BC or AO# BC to propagate the back calculation
		number	(BC) value from a downstream loop or AO. Also, program
			the upstream loop's feedback with this Math CV's back
			calculation value (CV# BC). You MUST program this CV's
			feedback to NONE if this CV is not used as part of a control
			loop output configuration (Figure 4-4). If it is part of a loop
			configuration, the math operator cannot be ABSVAL, SQRT,
			or STDDEV.

FB	BC	FB	BC
PID	INP 1	MATH	PID
		CV
			OR
			AO

Figure 4-4 Math CV Feedback Programming

114 Video Recorder – User Manual