Level Switch Version Vh; Reed Contact - Switching Of Inductive Or Capacitive Loads; Exclusion Of Liability - SIKA VH Notice D'utilisation

VH... / VK...
1.1.1 Level switch version VH...X
The Level switches for application in explosion-hazardous area have an "X" at the end of the
article number ( type plate). They have been subjected to an ignition hazard assessment in
accordance with DIN EN 13463-1: 2002 and correction 1: 2003 and do not have potential
sources of ignition. They are, therefore, not subject to directive 2014/34/EU.
The switching unit is a simple electrical instrument for connection to a certified intrinsically
safe circuit in accordance with DIN EN 60079-11: 2007. The effective internal inductances
and capacities are negligibly small.
The level switches series VH...X are designed for application in potentially explosive atmos-
phere. The ignition energy of the explosive atmosphere should not fall below 60 µJ.
Please observe the following separation of zones:
The design of the level switches series VH...X allows a potentially explosive atmosphere
(zone 0) to exist permanently, over a longer period or frequently within the tank in which the
float is located.
In normal operation, there should only be an occasional potentially explosive atmosphere
(zone 1) outside the tank where the level switch connection is located. A manufacturer's dec-
laration is available.

1.1.2 Reed contact - Switching of inductive or capacitive loads

CAUTION! Destruction or damage of reed contact!
Take notice of the max. contact loads mentioned on the specification plate!
The max. contact loads mentioned on the type plate (switching voltage, switching current
and switching capacity) refer to pure ohmic loads and may not be exceeded under any cir-
cumstances.
High voltage and current peaks can occur, particularly when switching inductive or capacitive
loads (e.g. relay coil, capacitors). Even if the overload is brief, this can destroy (welding the
contacts) or damage (reduced lifespan) the reed contact.
 Only use protection methods which be appropriate and checked.
Protection method when electrical connection of reed contacts:
The following protective circuits are basically possible: current limiting resistors, RC cir-
cuits, freewheeling diodes, suppression diodes, varistors or a combination of these.
Please verify the effectiveness of the chosen protection method in accordance with the spe-
cific loads involved.

1.2 Exclusion of liability

We accept no liability for any damage or malfunctions resulting from incorrect installation,
in-appropriate use of the device or failure to follow the instructions in this operating manual.
Technical changes reserved
Device description
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