TOHO ELECTRONICS TTM200 - Manual (Page 108)

48-7009-E 5-38
5.4.6 Loop abnormality function
■ What the loop abnormality is

The function is to detect an abnormality in the control loop.

When a value falls in the judgment domain with respect to the conditions of the control loop
anomaly MV threshold(MS*) and control loop anomaly PV threshold(tS*), the control loop anomaly
PV change threshold is judged at each “LoP*” time.

A loop abnormality is determined if each change threshold is judged to be equal to or below “PS*.”

When [PS* = 0] is true, only time judgment is executed using LOP*.
When the time satisfying threshold of TS* or MS* exceeds LOP*, the loop abnormality is
determined as detected.
(The symbol “*” takes the following values: “1” for the primary control and “2” for the secondary
control.)
The loop abnormality function is usable when one of OUT 1 to OUT 7 is selected for the event
loop abnormality existent.
About primary control loop abnormality-related setting ............................. P6-24~27
About secondary control loop abnormality-related setting .......................... P6-37~40
About event function 4 loop abnormality(E1~7F4) setting ......................... P6-44
Monitoring
time
（ＬｏＰ＊）
ON
OFF
ＳＶ
ＰＶ
ＭＬＬ＊
ＭＬＨ＊
ＭＶ＊
Monitoring
time
（ＬｏＰ＊）
Monitoring
time
（ＬｏＰ＊）
Loop
abnormality
Judgment
domain
Non-
judgment
domain
Judgment
domain
Non-
judgment
domain Control loop
anomaly PV
threshold
（ＴＳ＊）
Control loop
anomaly MV
threshold
（ＭＳ＊）