Flowserve NRS 1-7 User Manual
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Important Notes
Danger
The terminal strip of the NRS 1-7 is live during operation. This presents the danger of
electric shock!
Cut off power supply before attaching or detaching the housing lid and the terminal
strips of the equipment.
Usage for the intended purpose
Use level switch NRS 1-7 only in conjunction with level electrodes NRG 16-11, NRG 17-11,
NRG 19-11, NRG 111-11, NRG 16-11 S or NRG 16-38S for low-level limiting (low level alarm).
Safety note
The equipment must only be installed and commissioned by qualified and competent staff.
Retrofitting and maintenance work must only be performed by qualified staff who – through
adequate training – have achieved a recognised level of competence.
Explanatory Notes
Scope of supply
NRS 1-7
1 Level switch NRS 1-7
1 Installation manual
Description
Self-monitoring low-level alarm with periodic self-checking routine, designed for use in conjunction
with level electrodes NRG 16-11, PN 40, NRG 16-11S, PN 40, NRG 17-11, PN 63, NRG 19-11,
PN 160 and NRG 111-11, PN 320. The equipment combination detects the min. water level (low
level alarm).
Application in steam and (pressurized) hot water boilers in accordance with TRD 602 and TRD 604
sheet 1 and sheet 2 as well as EN 12952 and EN 12953.
ATEX (Atmosphère Explosible)
The equipment constitutes a simple item of electrical equipment as defined in DIN EN 50020 section
5.4. According to the European Directive ATEX 94/9/EC the equipment may only be used in potentially
explosive atmospheres if it is provided with approved Zener barriers.
Applicable in Ex zones 1, 2 (1999/92/EC). The equipment does not bear an EX marking. The suitability
of the Zener barriers is certified in a separate document.