Based on the "Standard Input" Model 4030, 4032, 4060, 4062, or 4077, each "4K/SPC" instrument provides true, on-line SPC in either bit-controlled operation (for discrete parts) or time-controlled operation (for continuous processes).
This is "true" SPC because it ensures a stable process not just within fixed "spec-determined" setpoints, but also within natural control limits continuously calculated from the process spread, using "±3-sigma" conventions.
And it's "on-line" because, with vivid analog and digital indication, plus TTL-level logic control outputs, it makes immediate control feedback possible. The operator can catch out-of-tolerance parts while they're still on the line, without having to wait for a computer to process "historical" measurement data.
Standard 4K/SPC models perform SPC operations on a single "live" measurement channel. In almost all cases, this is the "finished answer" channel of the base unit—or, in the case of base units with two analog inputs, an undedicated channel that may be assigned to either input or to a "Calculate" channel that operates on them both. Note, however, that a special modification of the 4K/SPC based on the Model 4032 or 4062 permits simultaneous SPC processing of both analog inputs.
4K/SPC features include
- Selectable digital and bargraph display of "LIVE" MEASUREMENT OR STATISTICAL DATA: X-BAR, R, Standard Deviation, Variance, and Mean Moving Range for the last complete subgroup; X-BAR-BAR, R-BAR, and Standard Deviation for the last 100 subgroups taken since SPC was reset
- User-defined SUBGROUP SIZE (2 to 25)
- CONTROL LIMITS, WARNING LIMITS, and SPECIFICATION LIMITS all continuously indicated by front-panel bargraph. Control and Warning limits may be fixed (as entered by the user) or calcaulted (continuously) derived from the monitored process). Logic outputs and front-panel annunciators are tied to the control-limit status of "live" data, X-BAR, and R (the outputs are shown in the following diagram). Default settings may be entered for control limits and statistical variables to prevent tripping of control outputs until a specified number of subgroups have been taken.
- On-board "HISTORY" MEMORY of up to 6000 individual sample readings, accessible via mnemonic command or the StartPAC 100 software supplied with every 4K/SPC unit (for specially modified DUAL-CHANNEL 4K/SPC MODELS, the history memory allows up to 3000 individual sample readings per SPC channel)
- Total part counting up to 32000
- Subgroup samples may be taken MANUALLY or AT A SPECIFIED TIME INTERVAL. When the 4K/SPC is set for "manual" sampling, you can take a reading by (1) pressing the front-panel TAKE button, (2) delivering a logic input to the rear panel via footswitch or other contact closure, or (3) entering a SAMPLE (SAM) command through an optional Model 10P80D Extended Keyboard or through the instrument's Computer Interface Port. The statistical process can be instantly stopped, started, or reset at any time.
- RS485 NETWORKING IS A STANDARD FEATURE OF EVERY 4K/SPC. Simple mnemonic commands may be issued by the network host—or by the local operator, via optional Model 10P80D Extended Keyboard—to control the entire statistical process or to access any and all statistical data stored in the instrument. See the summary of special 4K/SPC SETUP commands and RUN-TIME commands.
- StartPAC100 software with on-line HELP lets you set up the 4K/SPC quickly and easily. You can define and store multiple SPC FORMATS. Any format may then be downloaded into the instrument, depending on your current application requirements. In addition, the software contains routines for viewing and printing "Sample History" or current SPC variable data; for logging SPC data to disk; and for exporting SPC data to third-party software for later off-line analysis.