User Manual

SAFETY
Safety handbook page - 12 -
PNSPO
Once active operation of the emergency stop control has ceased following a stop
command, that command must be sustained by engagement of the emergency stop
device until that engagement is specifically overridden; it must not be possible to
engage the device without triggering a stop command; it must be possible to disengage
the device only by an appropriate operation, and disengaging the device must not
restart the machinery but only permit restarting.
Complex installations
In the case of machinery or parts of machinery designed to work together, the
manufacturer must so design and construct the machinery that the stop controls,
including the emergency stop, can stop not only the machinery itself but also all
equipment upstream and/or downstream if its continued operation can be dangerous.
4.1 Standards for E-Stop function :EN 418, EN 60204, EN 1037
The most relevant standards for e-stop applications are EN418, EN60204 and EN1037.
EN 418 contains functional aspects and principles for design. EN 60204 is about
Safety of machinery – electrical equipment of machines and EN 1037 explains
prevention of unexpected start-up of machines.
4.2 Requirements for E-Stop
EN 418 defines the functional aspects and principles for design of emergency stop
equipments such as e-stop push buttons, rope switches or foot-pedals. Devices
constructed according to EN 418 are useful for e-stop applications. The design is
illustrated by a graphic
O
p
eration
Rest
Time
A person becomes aware of the
necessity of an emergency stop
E-Stop
Status resulting
from
Emer
g
enc
y
sto
p
E-Stop
reset
E
E
N
N
4
4
1
1
8
8
Machinery can
be restarted