Rockwell Automation Low-Voltage Switchgear and Controlgear - Manual (Page 32)

ding is assured by an auxiliary contact before opening of the main contacts of the disconnec-
tor. Also circuit breakers with isolating function or other switchgear with isolating function and
motor switching capacity can be used as supply disconnecting devices, provided that they
fulfill the corresponding IEC standards.
- A supply disconnecting device must be manually actuated and have unambiguous “ON” and
“OFF” positions that are clearly marked with “
О” and “I”.
- A supply disconnecting device must either have a visible contact gap or a position indicator
which cannot indicate OFF (isolated) until all contacts are actually open and the require-
ments for the isolating function as specified under IEC 60947-3 have been satisfied.
- If the supply disconnecting device does not simultaneously serve as EMERGENCY STOP
device, it may not have a red handle (preferred colors black or gray).
- It must be possible to lock the handle in the “OFF” position (for example with a padlock).
- The supply-side terminals of supply disconnecting devices must be equipped with a finger
protection anti-tamper shield and a warning sign.
If required, supply disconnecting devices may be equipped with a door interlock device.
The power supply of the below circuits does not necessarily have to be controlled via the supply
disconnect switch:
- Lighting circuits that are required for maintenance work
- Sockets that are exclusively used for service equipment such as drills.
The requirements for supply disconnect switches can be fulfilled by switch-disconnectors, fuse-
switch-disconnectors and circuit breakers.
2.2.1.6 Supply disconnecting EMERGENCY STOP devices
If there is a real and present danger for man or machine, the dangerous parts of the machine or
the entire machine must be disconnected from the power supply by actuation of an
EMERGENCY STOP device as quickly as possible and brought to a standstill. According to IEC
60204-1 supply disconnecting devices are acceptable as local EMERGENCY STOP devices as
long as they are easily accessible for operating personnel. The below conditions must also be
fulfilled:
- For use as an EMERGENCY STOP device the handle must be red and on a yellow back-
ground.
- The device must be simultaneously able to interrupt the locked-rotor current of the largest
connected motor plus the sum of the rated currents of the remaining loads.
- It must be able to conduct the total rated operational current of all connected devices.
- The EMERGENCY STOP switch may not break those circuits that could lead to endanger-
ment of the personnel or the machine.
LVSAM-WP001A-EN-P - April 2009 2-4