Rockwell Automation 1336T Function Block Prog. Manual, Series A/B - Manual (Page 69)

Function Block Library 4–7
1336 FORCE — 5.9 August 1995
COMPHYST
BLOCK TYPE 4 decimal 4 hexadecimal
Compare w/Hyst
ID = Exec =
GT
NODE 0 In1
NODE 1
NODE 5
LT NODE 4
EQ NODE 3
Pre
NODE 2 Hyst
DEFINITION
Compares the input value In1 against a preset value Pre with an
associated hysteresis band Hyst and sets the appropriate indicator
flags.
EQ Output
FALSE
PRESET
FALSE TRUE
PRE (+) HYST PRE (–) HYST
INPUTS
In1 — Input value signed integer.
Pre — Preset value signed integer.
Hyst — Hysteresis band unsigned integer between 0 and + 32767.
OUTPUTS
EQ — Equal flag set to true when the input is within the hysteresis
band.
LT — Less than flag is set to true when In1 < Pre.
GT — Greater than flag is set to true when In1 > Pre.
FUNCTION
1. If In1
≤
Pre + Hyst and
≥
Pre – Hyst,
then EQ = true, else EQ = false.
2. If In1 > Pre,
then GT = true and LT = false.
3. If In1 < Pre,
then LT = true and GT = false.