I88-U1Z HW BERNSTEIN WERKZEUGFABRIK, I88-U1Z HW Datasheet - Page 5

• Manufacturer Part Number: I88-U1Z HW
• Description: LIMIT SWITCH, LEVER
• Manufacturer: BERNSTEIN WERKZEUGFABRIK

Specifications of I88-U1Z HW

• Actuator Style: Roller Plunger
• Switch Operation: Slow Action
• Contact Voltage Ac Max: 240V
• Contact Current Ac Max: 3A
• Switch Terminals: Screw Clamp
• Actuator Type: HW RO11
• Approval Bodies: CSA, CCC
• Rohs Compliant: Yes

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Common Features of Electromechanical Switches
p = Mechanical positive opening action
The term positive opening action refers to
contact separation as the direct result of
defined movement of the switch actuator
by means of non-sprung parts. All parts
involved in contact separation must be
form-fit connected. The positive opening
distance describes the minimum travel
distance from the start of actuation of the
operating element up to the point where
positive opening action of the opening
contacts is completed.
DIN EN 60947-5-1 defines two types of po-
sitive opening action contacts with 4 con-
nections and double break.
Type Za
l Positively opening contacts
Type Zb
l Positively opening contacts
Galvanic isolation describes the isolation
of electrically conducted parts by insulating
material or by air gaps.
In switching devices with several contact
elements, galvanically isolated contact
elements make it possible to switch volta-
ges with different potential (e.g. normally-
closed contact in safety circuit, normally-
open contact for indicator).
In accordance with applicable health and
safety requirements, protective devices
(guards) must be mounted on machines,
devices and systems that perform hazar-
dous movements. Safety switches in the
form of electromechanical switching devices
are predominantly used for this purpose as
they offer the following advantages:
l High degree of safety
l Non-susceptibility to interference
l Safety status easily checked on site
l Rational solutions
not galvanically isolated
galvanically isolated
Form-fit, mechanical drives or coupling
elements in the form of levers, rods,
gearwheels etc. are necessary to ensure
optimum operation of these safety
components.
Switching devices that are used for safety
functions must be identified with the
symbol p internationally standardised in
accordance with DIN EN 60947-5-1.
In defining the class of switching devices,
this symbol denotes two important proper-
ties that must be met for personal protection
applications:
l Mechanical positive opening action
l Disruptive breakdown voltage > 2.5 kV
Disruptive breakdown voltage
In accordance with DIN EN 60947-5-1, the
open contacts must be able to maintain a
minimum surge voltage of 2.5 kV without
disruptive breakdown.