Fanuc Ot 900 Parameter: List ^hot^

The Fanuc 0T 900 parameter list refers to the critical "option parameters" used to enable specialized software features and hardware capabilities on the Fanuc Series 0-T CNC control. While standard parameters control daily machine behavior like rapid speeds and stroke limits, the 900-series (ranging from 900 to 932) unlocks internal options such as canned cycles, custom macros, and memory expansions. Understanding the 900-Series Parameters

Unlike standard decimal or integer parameters, the 900-series are bit-type parameters. Each parameter consists of 8 bits (labeled 0 through 7), where setting a bit to 1 enables a specific function and 0 disables it. Core Option Parameter Examples

The following table highlights some of the most frequently referenced option parameters for the 0-T series: | Parameter | Bit | Description |

| :--- | :--- | :--- || 900 | 0 | Canned Cycle (G-codes like G80–G89) || 900 | 1 | G10 Program Input of Offset || 900 | 5 | Inch / Metric Conversion || 901 | 1 | Tape Memory Addition (120M) || 901 | 5 | Chamfering and Corner Radius || 901 | 7 | Multiple Repetitive Canned Cycles (G70–G76) || 902 | 2 | Constant Surface Speed Control || 902 | 6 | Custom Macro A || 903 | 7 | Soft Keys below CRT || 910 | 0 | Program Restart || 910 | 1 | Work Offsets (G54–G59) || 911 | 2 | Rigid Tapping | How to Access and Modify 900 Parameters

Modifying these parameters is restricted because they often relate to paid options from the machine tool builder (MTB). Enable Parameter Write (PWE): Switch the machine to MDI mode. Press the SETTING or PARAM hard key.

Find the PWE (Parameter Write Enable) setting and change it from 0 to 1. The CNC will typically trigger an alarm (e.g., P/S 100), which is normal. Navigate to the 900s: fanuc ot 900 parameter list

Press the SYSTEM or PARAM key again to view the parameter list.

Type 900 and press INPUT or use the PAGE DOWN keys to scroll to the correct page. Input New Values: Highlight the target bit.

Enter the 8-digit binary string (e.g., 00100101) and press INPUT. Finalize and Reboot: Set PWE back to 0. Press RESET to clear the alarm.

CRITICAL: Many 900-series changes require a full power cycle (OFF/ON) to take effect. Safe Handling and Risks Fanuc O-T Parameter List Overview | PDF - Scribd

The Problem with Parameter 900–939

Most operators know parameters 000–899: axis gains, acceleration times, RS232 settings. But parameters 900 through 939 are different. They are option parameters – they tell the CNC what hardware and software features are installed. The Fanuc 0T 900 parameter list refers to

Without them, the control doesn’t know:

• Does it have rigid tapping? (usually 910.#)
• Does it have a second axis? (900.#)
• What type of PMC (ladder logic) is installed? (903–906)
• Is there custom macro B? (or just basic macro A)

Diego’s machine was dead because the control had reverted to factory defaults: no options enabled, wrong PMC type, no axis configuration.

Part 7: Troubleshooting – When the 900 Parameters Go Wrong

Parameter 901 – Spindle Orientation & Encoder

| Bit | Function | |------|-----------| | 7 | Spindle orientation function (M19) available | | 6 | Orientation stop position setting (by parameter vs. auto) | | 5 | High-speed orientation response | | 4 | Encoder type: 0 = separate encoder, 1 = built-in motor encoder | | 3-0 | Orientation deceleration constant |

Parameter 900 – Axis Control Type

| Bit | Function | |------|-----------| | 7 | 0: X-axis not present / 1: X-axis present | | 6 | 0: Z-axis not present / 1: Z-axis present | | 5 | 0: No C-axis / 1: C-axis (spindle positioning) present | | 4 | 0: No 3rd axis / 1: 3rd linear axis (e.g., Y-axis on live tooling) | | 3-0 | Spindle type: 0000 = single speed, 0001 = two-speed, etc. |

Example: 10001000 (binary) = X axis present, Z axis present, no C, no 3rd axis, spindle type 0 (standard). The Problem with Parameter 900–939 Most operators know

Method 1 – Manual Recording

• Print or manually write down all parameters from 000 to 999 (yes, all).
• Pay special attention to 900–949. Copy them as an 8-character string per param.
• Store in two places: the machine’s electrical cabinet and a cloud drive.

Parameter 907 – High Speed Skip & Tapping

| Bit | Function | |------|-----------| | 7 | High-speed skip signal (G31 with P) enable | | 6 | Rigid tapping (M29) enable – very common on lathes | | 5 | Synchronous tapping with floating chuck | | 4 | Skip signal noise filter | | 3 | Retract after skip | | 2-0 | Skip input logic: 000 = skip via X4.7, 001 = X1.2, etc. |

Part 4: How to Read the Parameter List (Binary Basics)

Each 900 parameter is an 8-bit binary number, displayed in decimal format. To understand the "list," you must convert decimal to binary.

Example: Parameter 903 shows a value of 11001011 on the screen.

• Decimal displayed? That’s 203. No – on Fanuc OT, 900 parameters often show as binary digits directly, or a 3-digit decimal. More commonly, they display as 8 individual bits (0/1).
• On the screen, you will see:

0903 0 0 1 1 0 0 1 0

(Reading from right to left: bit 0 is the rightmost number)

To enable Macro B (MA2) on parameter 903, bit 0:
You need bit 0 = 1. If current is 0, change it. The display will update automatically.

✅ Common 900 Series Option Bits (Fanuc 0T Model C)

| Param | Bit | Function | |-------|-----|----------| | 900 | 0 | Helical interpolation | | | 1 | Scaling | | | 2 | Coordinate system rotation | | | 3 | User macro A | | | 4 | User macro B | | | 5 | Mirror image | | | 6 | DNC (tape mode) | | | 7 | Custom macro (global variables) | | 901 | 0 | Additional work offsets (6 pairs) | | | 1 | Tool life management | | | 2 | Tool offset memory C (wear/geometry) | | | 3 | G68/G69 coordinate rotation (milling) | | | 4 | Polar coordinate interpolation | | | 5 | Cylindrical interpolation | | | 6 | Skip function (G31) | | | 7 | High-speed skip | | 902 | 0 | Constant surface speed (G96/G97) | | | 1 | Multiple repetitive cycles (G70–G76) | | | 2 | Pattern repeat | | | 3 | Chamfering/rounding | | | 4 | Helical (already 900.0) | | | 5 | Thread cycle (G92) multiple start | | | 6 | G32 thread cutting | | | 7 | G34 variable lead thread | | 903 | 0 | Automatic tool position compensation | | | 1 | Tool nose radius compensation (G41/G42) | | | 2 | Tool offset measure (touch setter) | | | 3 | Program restart | | | 4 | Manual absolute ON/OFF | | | 5 | External data input | | | 6 | Rigid tapping (requires spindle encoder) | | | 7 | Spindle synchronization | | 904 | 0 | Background editing | | | 1 | Graphic display (tool path) | | | 2 | Program number search | | | 3 | Sequence number compare/stop | | | 4 | Tape punch format (ISO/EIA) | | | 5 | 2nd spindle control | | | 6 | Tool offset B (32 pairs) | | | 7 | Tool offset C (99 pairs) | | 905 | 0 | High-speed machining (G08) | | | 1 | AI contour control (Fanuc 0TC) | | | 2 | Nano smoothing | | | 3 | Small diameter drill cycle | | | 4 | Polygon turning | | | 5 | 2-axis synchronous feed | | | 6 | 3-axis control (lathe with live tooling) | | | 7 | C-axis control | | 906 | 0 | Manual guide (conversational) | | | 1 | Data server | | | 2 | Ethernet | | | 3 | Remote buffer | | | 4 | High-speed DNC (5/10/20 msec) | | | 5 | Memory card | | | 6 | Floppy disk interface | | | 7 | PCMCIA adapter | | 907 | 0 | Spindle load meter (analog output) | | | 1 | Part counter (input signal) | | | 2 | Power outage recovery | | | 3 | Automatic power off | | | 4 | Operation time display | | | 5 | Clock function | | | 6 | Maintenance timer | | | 7 | Operator message (100–199) | | 908 | 0 | 4th axis (A-axis) | | | 1 | 2nd spindle (sub-spindle) | | | 2 | Tailstock control | | | 3 | Parts catcher control | | | 4 | Bar feeder interface | | | 5 | Chip conveyor control | | | 6 | Door interlock override | | | 7 | Safety zone (stroke check) | | 909 | 0 | High-speed skip (duplicate) | | | 1 | Probe calibration (Renishaw) | | | 2 | Tool breakage detection | | | 3 | Adaptive feedrate | | | 4 | Learning control | | | 5 | Feed forward | | | 6 | Backlash acceleration | | | 7 | Dual drive control (two motors one axis) |