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NRS 1-51 - USA - Installation & Operating Manual -
850695-00
Usage for the intended purpose
The NRS 1-51 level switch is used in conjunction with NRG 1...-51 level electrodes as a high level
alarm for steam boilers and hot water installations.
A high level alarm prevents the defined high water (HW) level from being exceeded and switches
off the feedwater supply, for example, to achieve this. The NRS 1-51 is classified as protective
control Class B (C) in accordance with UL 60730-1.
When used as intended, the NRS 1-51 level switch is combined in a circuit with the level elec-
trodes stipulated by the directives or standards below:
Level electrodes NRG 1...-..
UL 60730-2-15,
CAN/CSA E60730-2-15
NRG 16-51
NRG 17-51
NRG 19-51
Applicable directives and standards
The equipment has been tested and approved for use in the scope governed by the following
directives and standards:
Standards:
■
UL 60730-1 and CAN/CSA E60730-1
General Requirements for Automatic Electrical Controls
■
UL 60730-2-15 and CAN/CSA E60730-2-15
Requirements for Automatic Electrical Water Level Sensing Controls
Improper use
There is a danger of death due to explosion if the equipment is used in potentially
explosive atmospheres.
Do not use the equipment in potentially explosive atmospheres.
Do not bring any equipment into service that does not have its own specific rating
plate.
The rating plate indicates the technical features of the equipment.
