GESTRA NRS 1-2, Руководство по установке

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Scope of supply
NRS 12
1 Level switch NRS 12
1 Installation manual
Explanatory Notes
Description
Level switch for indicating one high and one low liquid level (MIN alarm, MAX alarm), designed for
use with GESTRA level electrodes NRG 164, NRG 1...52, ER 50 and ER 56. Application in steam and
(pressurised) hot water plants according to TRD 602 and TRD 604, sheet 1 and sheet 2.
Function
The level switch NRS 12 has one channel and is designed for signalling one MAX and one MIN alarm.
The level switch has a manual test function. The button “TEST LW” can simulate a malfunction in the
level electrode. As a precaution in case of a power failure the normally closed contacts will trigger an
alarm in the event of power failure. The level switch features the following four operating modes:
n
Normal operation (no running dry, no high water)
n
MIN alarm (running dry)
n
MAX alarm (high water)
n
Alarm (malfunction in level switch or level electrode)
Two red LEDs indicate low water (LW), high water (HW) or system error alarm.
Components
NRG 164
Level electrode NRG 164 , PN 40
ER 50
Level electrode ER 50, NRG 1052 , PN 6
ER 56
Level electrode
ER 56, NRG 1652
, PN 40
Design
NRS 12
Plugin unit in plastic case for installation in control cabinets. The terminals in the case are
accessible after loosening two screws and unplugging the unit from its base.
To avoid confusion with other plugin units of the GESTRA range, inserts are fitted in the bases so
that only the correct unit may be plugged into each base.
The plugin unit may be snapped onto a 35 mm supporting rail or screwed into position on a
mounting panel.