Activation Of Safety Functions; Simultaneous Activation Of Safety Functions - Danfoss VLT MCB 150 Operating Instructions Manual

Functions and System Overvi...

3.2.3 Activation of Safety Functions

•
The safety functions are activated using the dual-
pole safe inputs on the safety option.
•
These inputs operate in accordance with the fail-
3 3
safe principle (on switching off). The safety
control system activates the safety functions via a
1/0 transition.
•
Deactivate the safety functions before applying
any changes to them.
3.2.4 Simultaneous Activation of Safety
Functions
All safety functions can be active at the same time.
However, Safe Torque Off has priority over all other safety
functions. Functions already started (e.g. Safe Stop 1 or
Safely Limited Speed) are canceled and the frequency
converter coasts.
•
Safe Torque Off has the highest priority. If the
Safe Torque Off function is triggered, a Safe
Torque Off is managed no matter what other
functions are active.
•
Safe Stop 1 has medium priority to the other safe
functions.
•
Safely Limited Speed has the lowest priority.
If 2 Safe Stop 1 functions are active at the same time, the
function with the steepest ramp has higher priority than
the function with less steep ramp.
If 2 Safely Limited Speed functions are active at the same
time, the function with the lowest speed limit has higher
priority than the function with higher speed limit.
If 2 equal safety functions have to be configured, they
must be parameterised as SS1-a and SS1-b or SLS-a and
SLS-b.
12
Operating Instructions
A Ramp stop function 1
B Ramp stop function 2
C Actual ramp stop function
Illustration 3.3 shows the result of activating first a Safe
Stop 1 function with a given ramp and afterwards
Danfoss A/S © Rev. 2014-02-11 All rights reserved.
A
B
C
Illustration 3.3 2 Safe Stop 1 Safety Functions Active
time
time
MG34W302