4
Important notes
Usage for the intended purpose
The level electrode NRG 16-36 is used in conjunction with level switch NRS 1-50 as water level limiter
for steam boilers and (pressurized) hot-water installations and in conjunction with level switches NRS
1-52 / NRS 1-54 or NRS 1-2 / NRS 1-5 as water level controller.
Water level limiters switch off the heating when the water level falls below the set minimum level (low
water).
Function
The
NRG 16-36
is a combination level electrode consisting of 1 level-limiting electrode tip for low level
alarm (LW) and 3 electrode tips for water level control with high level alarm (MAX).
The electrode operation is based on the conductive measuring principle using the electrical conductiv-
ity of the water for signalling water level. The high integrity self-monitoring function in the level limiter
ensures that an alarm will also be triggered if the electrode insulation is contaminated or has devel-
oped a leak and/or if there is a malfunction in the electrical connection.
The length of the individual electrode rods determines the switchpoints for the respective water levels.
The level electrode is installed inside steam boilers, vessels or in an external level pot. If the electrode
is installed inside the boiler or vessel, a protection tube provided on side ensures correct functioning.
(see section
Examples of installation
page 11).
If the level electrode is installed in an isolatable level pot outside the boiler, make sure that the con-
necting lines are rinsed regularly. In addition, the logic unit SRL is required to monitor the purging
times and the purging sequence. If the connecting lines for steam ≥ 40 mm and water ≥ 100mm, the
installation is considered to be internal. In this case the rinsing processes do not have to be monitored.
Safety note
Danger
When loosening the electrode steam or hot water might escape!
This presents the risk of severe scalding all over the body!
It is therefore essential not to dismantle the electrode unless the boiler pressure is
verified to be 0 bar.
The electrode becomes hot during operation.
Risk of severe burns to hands and arms.
Before carrying out installation and maintenance work make sure that the steam trap is
cold.
Attention
The name plate specifies the technical features of the equipment. Do not commission or
operate any item of equipment that does not bear its specific name plate.
This device is an item of equipment with safety function (PED) and must only be installed, wired 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.
