ci-server-engineer/.claude/skills/item-engineering/tasks/sub-items.md

task	version	source	status
Create sub-items (integrator, min-max)	R1.03	IM 36K10G10-01EN §3.1.5, §3.2.3; practiced with CI-Eng-Sample 2026-09-30	verified

Sub-items

A sub-item hangs under an item (<Section>.<Tag>.<Sub>) and processes the main item's value. Types: Integrator, Min-Max, Pulse, Rate-of-Change, Typeless. Sub-items cannot connect to equipment, cannot have sub-items, and are not blocked when the main item is blocked.

Quick load (SUB_ITEM_DF; the main item must exist):

@FIELDS
NAME,DESCRIPTION,SUB_TYPE,TIME_UNIT,MIN_MAX

@SUB_ITEM_DF
"CI-Eng-Sample.PUMP1.RUNNING.RUN_SECONDS","Pump 1 running time (seconds)","Integrator","",""
"CI-Eng-Sample.TANK1.LEVEL.MAX","Tank 1 maximum level","Min-Max","","Maximum"

Load with dssqld -i <file>.qli -l <file>.qlo; remove with a NAME-only file and dssqld -r (before removing the main item).

Behaviour (verified)

• Integrator adds value × seconds: with the main item at 1 it grows by 1 per second. TIME_UNIT (e.g. Hour) made no difference (knowledge/issues.md ISS-010); to show hours, divide by 3600 where the value is used.
• Min-Max with MIN_MAX = Maximum (or Minimum) keeps the highest (lowest) value written to the main item: writing 30, 70, 50 gave 70.
• TIME_UNIT (Second, Minute, Hour, Day) belongs to Rate-of-Change (from docs, not practiced).

Example files: examples/CI-Eng-Sample/02b_sub_item_df.qli, 90b_remove_sub_item_df.qli.