Casio fx-991W (S-V.P.A.M.)
The Casio fx-991W is a scientific calculator with 12 digits precision and formula input logic. It has 50 keys, and an LCD (liquid crystal) display. The power source is Solar + mercury cell. The calculator was manufactured in Japan.
Facts at a glance:
| Feature | Value |
|---|---|
| Type | Scientific |
| Keys | 50 |
| Precision | 12 |
| Logic | Formula |
| Display type | LCD |
| Length | 150mm |
| Width | 76mm |
| Thickness | 11mm |
| Weight | 138g |
| Power Source | Solar + mercury cell |
| Country | Japan |
| Year introduced | 1996 |
| Year discontinued | 2000 |
User Manual
You can download the Casio fx-991W manual from the manuals website.
Diagnostics
Note that diagnostic tests generally delete any data on the calculator. Be sure to back up any important information held in the calculator before running these tests.
Hold down SHIFT key and press reset button (on reverse - press pin into hole marked P). Press SHIFT to cycle through 5 display tests. Press REPLAY> key to enter keypad test (display flickers when a key is pressed). Use reset button to exit test.
Replacements:
If you have a Casio fx-991W that is no longer working, you can consider replacing the calculator with a modern equivalent.
We suggest the following current model as a replacement: