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Activation and Termination of Safe Stop
The safe stop function is activated by removing the voltage at Terminal 37 of the safe inverter. By connecting the safe inverter to external safety devices
providing a safe relay, an installation for a safe Stop Category 1 can be obtained. The Safe Stop function of AutomationDrive FC 302 can be used for
asynchronous and synchronous motors.
Safe stop activation (i.e., removal of 24 V DC voltage supply to terminal 37) does not provide electrical safety.
1.
Activate the Safe Stop function by removing the 24 V DC voltage supply to the terminal 37.
2.
After activation of Safe Stop (e.g., after the response time), the adjustable frequency drive coasts (stops creating a rotational field in the motor).
The response time is shorter than 10 ms for the complete performance range of AutomationDrive FC 302. For AutomationDrive FC 302 up to
10 hp [7.5 kW], it is even shorter than 5 ms.
The adjustable frequency drive is guaranteed not to restart creation of a rotational field by an internal fault (in accordance with Cat. 3 of EN 954-1). After
activation of Safe Stop, the AutomationDrive FC 302 display will show the text Safe Stop activated. The associated help text says "Safe Stop has been
activated. This means that the Safe Stop has been activated, or that normal operation has not been resumed yet after Safe Stop activation.
NOTE!
The requirements of Cat. 3 (EN 954-1) / PL “d” (ISO 13849-1) are only fulfilled while 24 V DC supply to terminal 37 is kept removed
or low by a safety device which itself fulfills Cat. 3 (EN 954-1) / PL “d” (ISO 13849-1).
In order to resume operation after Safe Stop is activated, 24 V DC voltage must first be reapplied to terminal 37 (text Safe Stop activated is still displayed);
second, a reset signal must be created (via bus, digital I/O, or [Reset] key on the inverter).
By default, the safe stop function is set to unintended restart prevention behavior. This means that in order to terminate the safe stop and resume normal
operation, the 24 V DC must first be reapplied to Terminal 37. Subsequently, a reset signal must be given (via Bus, Digital I/O or [Reset] key).
The Safe Stop function can be set to automatic restart behavior by setting the value of par. 5-19
Terminal 37 Safe Stop
from default value [1] to value
[3]. If an MCB112 option is connected to the drive, automatic restart behavior is set by values [7] and [8].
Automatic Restart means that Safe Stop is terminated, and normal operation is resumed, as soon as the 24 V DC are applied to Terminal 37, no reset
signal is required.
IMPORTANT! Automatic restart behavior is only allowed in one of the two following situations:
1.
Unintended restart prevention is implemented by other parts of the safe stop installation.
2.
A presence in the hazard zone can be physically excluded when safe stop is not activated. In particular, the following paragraphs of standards
under the EU Machinery Directive must be observed: 5.2.1, 5.2.2, and 5.2.3. of EN954-1:1996 (or ISO 13849-1:2006), 4.11.3 and 4.11.4 of
EN292-2 (ISO 12100-2:2003).
3.12.2 Installation of External Safety Device in Combination with MCB112
If the ex-certified thermistor module MCB112 which uses Terminal 37 as its safety-related switch-off channel, is connected, then the output X44/12 of
MCB112 must be AND-ed with the safety-related sensor (such as emergency stop button, safety-guard switch, etc.) that activates Safe Stop. This means
that the output to Safe Stop terminal 37 is HIGH (24V) only if both the signal from MCB112 output X44/12 and the signal from the safety-related sensor
are HIGH. If at least one of the two signals is LOW, then the output to Terminal 37 must be LOW, too. The safety device with this AND logic itself must
conform to EN 954-1, Safety Category 3. The connection from the output of the safety device with safe AND logic to Safe Stop terminal 37 must be short-
circuit protected. See figure below:
3 Introduction to AutomationDrive FC 300
FC 300 Design Guide
3-42
MG.33.BC.22 - VLT
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