Danfoss VACON OPTEA User Manual

The acceleration ramps are valid only for the SSR function. The acceleration ramps are defined in the same way as deceleration
ramps. A nominal speed value (shared with the deceleration ramp) and two time values that represent the maximum and minimum
time that the ramping is permitted to take. The actual monitored ramps are calculated when ramp monitoring starts.
SSR_Acc_max s = 
(SSR_Min_Limit rpm − Speed rpm ) × Ramp_Acc_Time_Min s
Rampx_speed rpm
SSR_Acc_min s = 
(SSR_Min_Limit rpm − Speed rpm ) × (Ramp_Acc_Time_Min s − SSR_td1 s
Rampx_speed rpm
where Speed is the speed at the time of the calculation. SSR_Acc_Max and SSR_Acc_Min are the time from ramp start (A and B)
where speed should be at the monitored minimum limit speed (C and D). Rampx_speed is the nominal speed for the ramp set. At
any given point during the ramp monitoring the actual value of monitoring is calculated from the slope connecting the respective
points.
C
A
D
B
Speed
Nominal Acceleration Ramp
Scaled Acceleration Ramp
Rampx Speed
SSR Max Limit
SSR Min Limit
Speed
SSR td1
SSR Acc Min
SSR Acc Max
Rampx Acc Time Min
Rampx Acc Time Max
t
e30bi386.10
Illustration 27: Acceleration Ramps, the SSR Function as an Example
A
Start of the minimum acceleration ramp
B
Start of the maximum acceleration ramp
C
End of the minimum deceleration ramp
D
End of the maximum deceleration ramp
N O T I C E
The response to a ramp violation is the STO(+SBC) function for safe stopping functions, and the SQS function for safe monitoring
functions.
6.2 Safe Stopping Functions
6.2.1 Introduction to the Safe Stopping Functions
The safe stopping functions are used to start and monitor the stopping of the motor. The safe stopping functions do not take into
account the rotation direction of the motor when they are in the optional zero speed or the ramp monitoring mode. The SOS func-
tion is an exception, it takes into account the rotation direction of the motor.
The priority of the safe stopping functions from the highest to the lowest:
1. The STO function
2. The SQS function
AQ319736045637en-000101 / DPD0179866 | Danfoss A/S © 2021.06
Safety Functions
VACON® NXP Advanced Safety Options
Operating Guide

Danfoss VACON OPTEA Specifications

General

Brand	Danfoss
Model	VACON OPTEA
Category	DC Drives
Language	English