Item Qualities
When using External Item Data Validation, Apis Hive will mark the item quality with Prediktor-specific qualities when validation fails. In compliance with the OPC DA specification, vendor specific item qualities are supported inside the upper 8 bits of the 16-bit quality word.
Apis uses the following item qualities:
| Quality name | Quality value(16 bit word) | Description |
|---|---|---|
| bad quality | 256 | Item value had bad quality |
| range | 257 | Item value failed range check |
| roc | 258 | Item value failed rate of change check |
| watchdog | 259 | Item value failed watchdog check |
| difference | 260 | Item value failed difference check |
| abs difference | 261 | Item value failed absolute value of difference check |
| spc unable | 262 | Item value failed SPC check cause unable to perform check (ie. data conversion failure) |
| spc 1beyza | 263 | Item value failed SPC check cause One point beyond zone A |
| spc 9beycent | 264 | Item value failed SPC check cause Nine points in a row in zone C or beyond on one side of CL |
| spc 6incdec | 265 | Item value failed SPC check cause Six points in a row steadily increasing or decreasing |
| spc 14altupdo | 266 | Item value failed SPC check cause Fourteen points in a row alternation up and down |
| spc 2of3inza | 267 | Item value failed SPC check cause Two out of three points in a row in zone A or beyond |
| spc 4of5inzb | 268 | Item value failed SPC check cause Four out of five points in a row in zone B or beyond |
| spc 15inzc | 269 | Item value failed SPC check cause Fifteen points in a row in zone C above or below CL |
| spc 8outzc | 270 | Item value failed SPC check cause Eight points in a row on both sides CL with none in zone C |