Ramp Monitoring; The Ss1 Signals - Danfoss Vacon OPTEA Operating Manual

VACON® NXP Advanced Safety Options
Operating Guide
When zero speed monitoring is used, time monitoring is also used. Zero speed monitoring monitors if the motor stops. The stop-
ping of the motor is determined by parameter Zero Speed. When zero speed monitoring is used, the speed going below the zero
speed starts a delay time set in SS1 td2 after which the SS1 function is reached. When the SS1 function is reached, the STO function
becomes active. The SS1 function must be reached before the time that is set in SS1 t1 elapses. If SS1 t1 elapses first, the STO func-
tion is activated as a violation response, not as a regular STO safety function.
If the SBC function is used, the moment when the brake output becomes active depends on the parameterization of the SBC func-
tion. See 6.2.2.3 The STO Function Used with the SBC

6.2.3.4 Ramp Monitoring

Speed
Zero speed /
SBC speed
Illustration 37: The SS1 Function in the Time + Zero Speed + Ramp Monitoring Mode
When ramp monitoring is used, zero speed monitoring and time monitoring are also used. Ramp monitoring monitors that the
deceleration speed obeys the set deceleration ramp. Select the monitored ramp with parameter SS1 Ramp Monitoring. The ramp
can be static or dynamically selected by a digital input or a fieldbus. It is possible to monitor the minimum ramp, the maximum
ramp, or both these ramps.
The ramp monitoring starts after the time delay that is set with SS1 td1 has passed. SS1 td1 starts when the SS1 function starts its
operation. The ramp monitoring ends when the SS1 function is reached. If the speed does not obey the parameterized ramp during
the monitoring, the STO function becomes active as a violation response.
When using dynamic ramp from digital input or fieldbus, the monitored ramp is determined at the moment when the SS1 function
is requested. The changes that are made after this do not affect the operation of the function.

6.2.3.5 The SS1 Signals

It is possible that the Active and Reached signals that are mentioned in this chapter are not always available in all interfaces.
The availability of the signals over safe fieldbus depends on the used fieldbus protocol. Refer to chapter Safe fieldbuses for more
information.
Table 32: The SS1 Signals
Signal Activation and deactivation of the signal
SS1 Active Activation:
• SS1 is requested and starts execution.
Deactivation (manual acknowledgment):
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Function.
SS1 td1
SS1 td2
N O T I C E
STO +
SBC
SS1 t1
AQ319736045637en-000101 / DPD01798 | 75
Safety Functions
t
Description
The signal indi-
cates if SS1 func-
tion is being exe-
cuted.