Pitagora 4.0 – Rollback control and comfort adjustment

Contents

When the Pitagora controller is applied to installations equipped with closed loop gearless machines, comfort and precision can be optimized thus avoiding undesired effects such as rollback (typical of lifts with unbalanced load).
The following parameters can be adjusted to achieve optimal setting for your installation. It is suggested to follow the procedure from start to end in the proposed sequence.

Starting phase adjustments

Parameter	Description	Suggested adjustments	Default
			Geared	Gearless
F24	Starting speed holding time	Do not change this value, unless the installation is equipped with digital positioning system (Magnetic readers)	0,2	0,2
H64	Zero speed control time	Set value between 0,7 and 0,8 then increase to soften start phase ramp. Important: Enter the "Positioning" Menu and check parameters DIR-BRK (must be kept low: 0,1-0,2) and BRK-S (must be kept higher than H64)	0,8	0,8
H65	Soft Starter activation	Do not change this value	0,5	0,5
L66	RBC activation time at zero speed (Specifies the maximum time length for estimating an unbalanced load)	Do not change this value	2 s.	2 s.
L68	RBC Proportional Gain (P constant) (specifies the P constant of the Automatic Speed Regulator to be used during RBC calculation time)	Motor overshoots: increase value by 0,25 Vibrations: decrease value by 0,25	10	1,8
L69	RBC Integral Time (I constant) (specifies the I constant of the Automatic Speed Regulator to be used during RBC calculation time)	Motor overshoots: decrease value by 0,001 Vibrations: increase value by 0,001	0,010 s.	0,0003 s.
L73	Unbalanced load compensation (specifies the I constant of the Automatic Position Regulator to be used during RBC calculation time)	Motor overshoots: increase value by 0,50 Vibrations: decrease value by 0,50	0	0,5
L05	Proportional gain current loop starting phase	It depends on the type of machine	1,5	1,5
L80	Brake Control (Mode)	Do not change this value	1	1
L82	ON delay time (specifies the delay time during which the inverter main circuit is kept activated)	Larger Brakes: decrease value by 0,1 Smaller brakes: increase value by 0,1	0,2 s.	0,2 s.

High speed phase adjustments

Parameter	Description	Suggested adjustments	Default
			Geared	Gearless
L36	P" Gain constant at high speed	Speed fluctuations: increase value by 0,25 Vibrations: decrease value by 0,25	10	2
L37	I" Time I constant at high speed	Speed fluctuations: decrease value by 0,01 Vibrations: increase value by 0,01	0,100 S.	0,100 S.

Low speed adjustments

Parameter	Description	Suggested adjustments	Default
			Geared	Gearless
L38	P" Gain constant at low speed	Motor stops: increase value by 0,25 Vibrations: decrease value by 0,25	10	2
L39	I" Time I constant at low speed	Motor stops: decrease value by 0,01 Vibrations: increase value by 0,01	0,100 S.	0,100 S.

Stopping phase adjustments

Parameter	Description	Suggested adjustments	Default
			Geared	Gearless
F25	DC Brake Parameters Stop Speed	Do not change this value	0,1	0,1
L38	"P" Gain constant at low speed	Car unable to stay at floor: increase value by 0,25 Vibrations: decrease value by 0,25	10	2
L39	"I" Time I constant at low speed	Car unable to stay at floor: decrease value by 0,01 Vibrations: increase value by 0,01	0,100 s.	0,100 s.
H67	Stop speed holding time	Car unable to stay at floor: increase value by 0,25 (Max: 1,0 s) Important: Enter the "Positioning" Menu and check parameters BRK- DIR (must be kept at 2 s) and Stopping Boost (set between 1% and 2%)	1,5 s.	1,5 s.
L80	Brake Control (Mode)	Do not change this value	1	1
L82	ON delay time (specifies the delay time during which the inverter main circuit is kept activated)	Larger Brakes: decrease value by 0,1 Smaller brakes: increase value by 0,1	0,2	0,2
L83	Brake Control (OFF delay time) (specifies the delay time between stop speed and turning off of the brake signal)	Larger Brakes: decrease value by 0,1 Smaller brakes: increase value by 0,1	0,1 s.	0,3 s.
E16	Deceleration time # 9 (Last deceleration ramp)	Increase value by 0,5 to soften last ramp (max suggested value: 3 sec)	1,80 s.	1,80 s

Case VVVF controllers with non-encoder based positioning systems

Parameter	Description	Suggested adjustments	Default
			Geared	Gearless
F24	Starting speed holding time	Set value between 0,7 and 0,8	1	0,1
E12	Acceleration at high speed	Speed fluctuations: increase value by 0,25	2	2
E13	Acceleration at low speed	Motor stops: increase value by 0,25	2	0,100 s.
C07	Creep Speed (10% of high speed)	Motor stops: increase value by 0,1 Vibrations: increase/decrease value by 0,1		1,5 s.
C11	High Speed	If the car is unable to keep floor level, make sure the low speed phase is performed correctly by reducing high speed C11 to half of its value to check that low speed is kept for few seconds, then slowly increase C11.	See Nominal Value on the motor plate	1

**Fire operation programming procedure**

Updated on 9 Giugno 2025

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Starting phase adjustments

High speed phase adjustments

Low speed adjustments

Stopping phase adjustments

Case VVVF controllers with non-encoder based positioning systems

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