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NRR 2-50, NRR 2-51 - USA - Installation & Operating Manual -
850699-00
Usage for the intended purpose
The NRR 2-50, NRR 2-51 level controller is used in combination with the NRGT 26-2 level trans-
mitter as a limit switch and water level controller, e.g., in steam boilers and hot water installa-
tions or in condensate and feedwater tanks. The level controller indicates when a MIN and MAX
water level has been reached, and opens or closes a control valve.
The NRR 2-50 and NRR 2-51 are classified as operating controls in accordance with UL 60730-1.
When used as intended, the NRR 2-50, NRR 2-51 level controller can be combined in a circuit with an
NRGT 26-2 level transmitter.
To ensure proper use in all applications, please also read the Installation & Operating
Manuals for the system components used.
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You can find the latest Installation & Operating Manuals on our website:
http://www.gestra.com
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.
Applicable directives and standards
The equipment has been tested and approved for use in the scope governed by the following
directives and standards:
Standards:
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UL 60730-1 and CAN/CSA E60730-1
General Requirements for Automatic Electrical Controls
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UL 60730-2-15 and CAN/CSA E60730-2-15
Requirements for Automatic Electrical Water Level Sensing Controls
