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Level Switches (intrinsically safe)

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BS 70*/71*

Product Description and Application
  • They act as level monitors and also as dry running or overflow indicators and they are used, in conjunction with a coupling switch, for controlling pump motors or solenoid valves in intrinsically safe circuits
  • Applicable in water, sewage, mildly corrosive liquids, oil (without aromatic additives) and fuel oil
  • Applicable as contact makers and signal transmitters (FULL/EMPTY)
  • Installation position: suspended on cable
  • Switching function: switching over when passing through the horizontal
  • Tubular plastic enclosure, completely sealed
  • Type BS 70 floats on the surface of the medium
  • Type BS 71 in standard form preset to sink to a depth of 1.5 metres, variable immersion depth

 

Type of explosion protection: mining
ex I M2 EEx d I
Type of explosion protection: industry
ex II 2G EEx ia IIC T6
Degree of enclosure protection
IP 68
EC type examination certificate
IBExU 99 ATEX 1093
Model and Performance Variants
Typ   Kontaktgebung
BS 70
BS 71
With optical
signal (LED)
By 2 series-connected LED
BS 70/o
BS 71/o
Supply voltage
230 Volt
With an electronic switch (mercury tube switch),
being designed as changeover switch
BS 70/os
BS 71o/s
Supply voltage
230 Volt
By a changeover switch (mercury tube switch),
connected in series with 2 anti-parallel diodes
BS 71/2-3
With optical
signal (LED)
By 2 parallel working NO-switches,
connected in series with one LED each
BS 71/2-4
With optical
signal (LED)
By 2 parallel working CO-switches,
connected in series with anti-parallel diodes
BS 70 MS
BS 71 MS
With optical
signal (LED)
By a changeover switch (snap-action contact switch),
connected in series with 2 LED
BS 70 NS
BS 71NS
With optical
signal (LED)
With 2 separate inclination switches, consisting of one
NC- and one NO-contact, connected in series
with one LED each
Design – Technical Specifications
Installation position
Suspended on cable
Switching function Switching over when passing through the horizontal
Floating body material Polypropylene, flame-resistant
Floating body dimensions
BS 70* = 163.5 x 32 mm
BS 71* = 163.5 x 55 mm
Immersion depth

BS 70* - floats on the surface
BS 71* - in standard form sinking to a depth of 1.5 m
(variable if required)

Cable Oil resistant and ultraflexible 3 x 0.75 mm² blue, 
optionally HO5VV-F 3 x 1 mm², blue
Length of connecting lead As required, up to 75 m max.
Temperature stability Max. + 60° C (higher temperatures on request)
Pressure resistance Max. 6 bar
Contact Depends on selected item,
specific information see catalogue data sheet (pdf)
Switching angle Depends on selected item,
specific information see catalogue data sheet (pdf)
Voltage Depends on selected item,
specific information see catalogue data sheet (pdf)
Amperage Depends on selected item,
specific information see catalogue data sheet (pdf)
Electrical connection To intrinsically safe circuits Ex i,
e. g. via coupling switch

 

Subject to technical modifications!

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