Flowserve NRS 1-50 For TWO Electrodes - Manual (Page 5)

5
Directives and Standards
Pressure Equipment Directive (PED) 97/23/EC
Water level limiters are safety accessories as defined in the Pressure Equipment Directive (PED). The level
switch NRS -50 in conjunction with level electrode NRG ...-50 and NRG 6-36 is EC type
approved according to EN 95/EN 953. These Directives state, among other things, the requirements
made on limiting systems and equipment for steam boiler plants and (pressurised) hot-water installations.
ATEX (Atmosphère Explosible)
According to the European Directive 94/9/EC the level switch NRS -50 must not be used in potentially
explosive areas.
Note
The level electrodes NRG ...-50, NRG ...- and NRG 6-36 are simple items of electrical
equipment as specified in EN 60079- section 5.7. According to the European Directive
94/9/EC the equipment must be equipped with approved Zener barriers if used in potentially
explosive areas. Applicable in Ex-zones ,  (999/9/EC).
The equipment does not bear an Ex marking. The suitability of the Zener barriers is
certified in a separate document.
Note that the requirements of the IEC 6508 are not met if the NRG ...-50, NRG ...-
and NRG 6-36 + Zener barriers + NRS -50 are interconnected!
VdTÜV Bulletin “Wasserstand 100” (= Water Level 100)
The level switch NRS -50 in conjunction with the level electrodes NRG ...-50, NRG ...- and
NRG 6-36 is type approved according to the VdTÜV Bulletin “Water Level 00”.
The VdTÜV Bulletin “Wasserstand (=Water Level) 00” specifies the requirements made on water level
control and limiting equipment for boilers.
Functional Safety acc. to IEC 61508
The level switch NRS -50 is certified acc. to IEC 6508 only if used in combination with level
electrode NRG ...-50 / NRG 6-36 . This standard describes the functional safety of safety-related
electrical/electronic/programmable electronic systems.
The equipment combination NRG ...-50 or NRG 6-36 + NRS -50 corresponds to a type B
subsystem with Safety Integrity Level (SIL) 3.
Approvals for Marine Applications
The level switch NRS -50 in conjunction with level electrodes NRG 6-50S/NRG 6-S/NRG 6-38S
and NRG 6-39S is approved for marine applications.
We can present approvals issued by Germanischer LLoyd and Lloyd's Register.
LV (Low Voltage) Directive and EMC (Electromagnetic Compatibility)
The level switch NRS -50 meets the requirements of the Low Voltage Directive 006/95/EC and the
EMC Directive 004/08/EC.