They are stored in (Static RAM) backed by a battery. If the battery dies, these parameters are lost—and the machine becomes a brick.
For daily operators, your job is to and never modify these values unless under service guidance. For maintenance engineers, understanding bits like 904.7 (PMC enable) and 908.7 (turret type) will save hours of downtime. fanuc ot 900 parameter list
| Machine Builder | Typical 900 Params (examples) | Notes | |----------------|--------------------------------|-------| | (OSP 7000L) | 906 bit 0=1 (dogless reference), 908 bit5=1 (shortest path turret) | Uses absolute encoders – 900 params must match encoder type | | Mori Seiki (SL series) | 907 bit6=1 (rigid tapping), 910 bit7=1 (4th axis live tooling) | Heavy use of 904 PMC ladder protection | | Hardinge (T42, Conquest) | 902 bits 7-6=10 (PMC-R), 908 bit3=1 (random tool selection) | Unique tool changer logic tied to param 941-944 | | Haas (HL-1, HL-2 – early models) | 905 bit7=1 (custom macro), 909 bit4=1 (DNC with no parity) | Haas used modified FANUC OT firmware – check service manual | They are stored in (Static RAM) backed by a battery