8 ISD Safety Concept
NOTE
It is the responsibility of the user to install and use the
safe stop function correctly. Observe the following:
•
Read and understand the safety regulations
regarding occupational health and safety.
•
Ensure that the basic and special provisions
regarding the safety functions in the descriptions
in this and more detailed documents are
understood
•
A sufficiently familiarity with general and safety-
related standards relevant to the specific
application is required
•
Carry out a hazard and risk analysis
•
Demonstrate the safety of the overall system
Read and understand the detailed safety instructions in
.
Only PELV power supply units may be used.
Safety circuitry must always be wired and operated using
conductors and original accessories intended for this
purpose. Only original Danfoss cables may by used for
cabling between the drives and between the connection
box and a drive. Using any other cable will defeat the safe
stop function as described in the standards listed below.
The safe stop function of the servo drive is used for
synchronous ISD motors. In the event of several concurrent
faults, in very rare cases a residual rotation of 22.5
°
may
occur. It must be ensured that this residual rotation cannot
create a hazard.
Pulsed semiconductor outputs may not be used with
safety devices. The safe stop function can be used when it
is necessary to perform mechanical work on the machine.
This function does not provide electrical safety in the
sense of the VDE regulations. The supply voltage of the
drives is not disconnected by this function.
The machine manufacturer is responsible for taking
additional safety measures. The holding torques of the
servo drive and the optional brake do not constitute safety
functions. If hazards are present, additional measures must
be taken, such as protective fences, barriers and exclusion
of persons from hazard areas.
WARNING
UNCONTROLLED SERVOMOTOR COASTING
Uncontrolled coasting of the servo drive occurs when
Category 0 Stop (Safe Torque Off) is used. This depends on
the inertia of the external mass driven by the motor.
Additional measures must be taken if this is not
permissible following a risk analysis. See also the example
circuit in
8.1 Standards
If the safe stop function accessed via pin 4 of the drive is
used, the user must ensure compliance with all regulations
and prerequisites for safety, including applicable statutes,
standards, directives and guidelines. The safe stop function
conforms to the following standards:
•
EN 60204-1: 2005 Stop Category 0
•
IEC 61508: 1998 SIL 2
•
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 start
To install and use the safe stop function in accordance
with the requirements of Safety Category 3 PL d
(ISO 13849-1), the related information and instructions on
the proper and safe use of the safe stop function in the
connection box operating instructions must be followed.
8.2 Functional Description
The ISD 410 servo drive is equipped with the Safe Torque
Off function under EN IEC 61800-5-2 and Stop Category 0
under EN 60204-1. Danfoss calls this function "Safe Stop".
It has been developed and tested as suitable for
requirements conforming to:
•
Category 3 under EN ISO 13849-1
•
Performance Level d under EN ISO 13849-1
•
SIL 2 under EN IEC 61508 and EN 61800–5–2
•
SIL CL 2 under EN 62061
ISD Safety Concept
VLT
®
ISD 410 Servomotor Operating Instructions
MG75D102 - VLT
®
is a registered Danfoss trademark
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