Rockwell Automation 1336T Function Block Prog. Manual, Series A/B - Manual (Page 106)

Function Block Library 4–44
1336 FORCE — 5.9 August 1995
RATE LIMITER
BLOCK TYPE 19 decimal 13 hexadecimal
Rate Limiter
ID = Exec =
Lim Out
NODE 0 Lim In
NODE 1
NODE 5
Lim @ Lim NODE 4
Lim Set
NODE 2 Lim Data
NODE 3 Lim Rate
DEFINITION
Limits the rate of change of the input value Lim In by the value of
rate Lim Rate.
INPUTS
Lim In — A signed integer that is rate limited in the positive or
negative direction.
Lim Set — A logic value that preloads the output with the
Lim Data value when Lim Set
≠
0.
Lim Data — A signed integer that the output will be set to when
Lim Set
≠
0.
Lim Rate — A word that specifies the Lim Out maximum rate of
change in units/second.
OUTPUTS
Lim @ Lim — A logic flag that indicates Lim Out is limited by
Lim Rate.
Lim Out — A signed integer, rate limited to the Lim Rate value.
FUNCTION
1. If Lim Set is true, Lim Out = Lim Data.
2. If Lim Set is false,
∆
= Lim In – Lim Out.
If
∆
is + and > Lim Rate, Lim @ Lim is true and
∆
= Lim Rate.
If
∆
is + and < Lim Rate, Lim @ Lim is false.
If
∆
is – and < – Lim Rate, Lim @ Lim is true.
If
∆
is – and > – Lim Rate, Lim @ Lim is false.
Lim Out = Lim Out +
∆
.