SISTEMA Data
Functional safety data is available via a data library for use
with the SISTEMA calculation tool from the IFA (Institute
for Occupational Safety and Health of the German Social
Accident Insurance), and data for manual calculation. The
library is permanently completed and extended.
1.6.1 Terminal 37 Safe Stop Function
The frequency converter is available with safe stop
functionality via control terminal 37. Safe stop disables the
control voltage of the power semiconductors of the
frequency converter output stage. This in turn prevents
generating the voltage required to rotate the motor. When
the Safe Stop (T37) is activated, the frequency converter
issues an alarm, trips the unit, and coasts the motor to a
stop. Manual restart is required. The safe stop function can
be used as an emergency stop for the frequency converter.
In normal operating mode when safe stop is not required,
use the regular stop function instead. When automatic
restart is used, ensure the requirements of ISO 12100-2
paragraph 5.3.2.5 are fulfilled.
Liability Conditions
It is the responsibility of the user to ensure that qualified
personnel installs and operates the safe stop function:
•
Read and understand the safety regulations
concerning health and safety/accident prevention
•
Understand the generic and safety guidelines
given in this description and the extended
description in the relevant Design Guide
•
Have a good knowledge of the generic and safety
standards applicable to the specific application
User is defined as: integrator, operator, service technician,
maintenance technician.
Standards
Use of safe stop on terminal 37 requires that the user
satisfies all provisions for safety including relevant laws,
regulations and guidelines. The optional safe stop function
complies with the following standards.
•
IEC 60204-1: 2005 category 0 – uncontrolled stop
•
IEC 61508: 1998 SIL2
•
IEC 61800-5-2: 2007 – safe torque off (STO)
function
•
IEC 62061: 2005 SIL CL2
•
ISO 13849-1: 2006 Category 3 PL d
•
ISO 14118: 2000 (EN 1037) – prevention of
unexpected startup
The information and instructions of the instruction manual
are not sufficient for a proper and safe use of the safe stop
functionality. The related information and instructions of
the relevant Design Guide must be followed.
Protective Measures
•
Qualified and skilled personnel are required for
installation and commissioning of safety
engineering systems
•
The unit must be installed in an IP54 cabinet or
in an equivalent environment. In special
applications a higher IP degree is required
•
The cable between terminal 37 and the external
safety device must be short circuit protected
according to ISO 13849-2 table D.4
•
When external forces influence the motor axis (for
example, suspended loads), additional measures
are required (for example, a safety holding brake)
to eliminate potential hazards
Safe Stop Installation and Set-Up
WARNING
SAFE STOP FUNCTION!
The safe stop function does NOT isolate mains voltage to
the frequency converter or auxiliary circuits. Perform work
on electrical parts of the frequency converter or the motor
only after isolating the mains voltage supply and waiting
the length of time specified in Table 1.1. Failure to isolate
the mains voltage supply from the unit and waiting the
time specified could result in death or serious injury.
•
It is not recommended to stop the frequency
converter by using the Safe Torque Off function.
If a running frequency converter is stopped by
using the function, the unit trips and stops by
coasting. If unacceptable or dangerous, use
another stopping mode to stop the frequency
converter and machinery, before using this
function. Depending on the application, a
mechanical brake can be required.
•
For synchronous and permanent magnet motor
frequency converters, in a multiple IGBT power
semiconductor failure: In spite of the activation of
the Safe Torque Off function, the system can
produce an alignment torque which maximally
rotates the motor shaft by 180/p degrees. p
denotes the pole pair number.
•
This function is suitable for performing
mechanical work on the system or affected area
of a machine only. It does not provide electrical
safety. Do not use this function as a control for
starting and/or stopping the frequency converter.
Follow these steps to perform a safe installation of the
frequency converter:
Introduction
VLT
®
AQUA Drive
Operating Instructions
MG20M902 - VLT
®
is a registered Danfoss trademark 9
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