The relationship between time constant (T) and acceleration (a) is:
Detection units (dependent on machine resolution, typically 0.001 mm or 0.0001 inch)
Disclaimer: Parameter numbers and behavior can vary slightly between FANUC control series (e.g., 0i-TD vs 31i-A). Always refer to the specific FANUC operator’s manual for your control model. fanuc parameter 1860 full
2. Full-Closed Loop Systems (Linear Scales / External Encoders)
How to confirm exact definition for your controller: The relationship between time constant (T) and acceleration
Increase 1860 by 10–20% increments. Also verify that the motor torque limit (parameter 1640/1641) is adequate.
Known as BLEN , this bit must be set to 1 to enable backlash acceleration functions. Commonly Confused Parameter: 1815 Full-Closed Loop Systems (Linear Scales / External Encoders)
This article provides a full technical breakdown of Parameter 1860—its function, its relationship with other parameters, how to calculate it, common troubleshooting scenarios, and best practices for optimization.
If Parameter 1860 is set incorrectly (e.g., after a servo swap or battery backup loss), the following issues will occur:
Change from 0 to 1 . Ignore the resulting flashing P/S alarm. Navigate to Parameter 1860: Press the SYSTEM hard key. Press the PARAM soft key. Type 1860 and press the No. SRCH (Number Search) soft key. Input the Value:
