9
Installation
Note
One level electrode NRG 26-21 can be installed together with one GESTRA level elec-
trode, one level switch or transmitter in a single protection tube or an external level pot
(inside diameter DN80/DN100).
Fig. 4 - 7.
If the level limiting electrode is installed
inside the vessel, it must be at least 40 mm away from the upper vent hole.
For the approval of the boiler standpipe the relevant regulations must be considered.
Refer to pages 10 and 11 for typical installation examples.
The angle of inclination of the electrode must not exceed 45°, with the length of the
electrode being limited to 688 mm.
Fig. 8
If installed outdoors the level electrode
must
be equipped with a GESTRA weather
protection cover.
The seating surfaces of the standpipe or the flange provided on the vessel must be
accurately machined,
Fig. 3
!
Do not bend electrode tip when mounting.
Do not subject electrode to physical shocks.
Use only the supplied joint ring.
Joint ring 27 x 32, form D, DIN 7603, 2.4068, bright annealed
Do not lag electrode body above the hexagonal section.
Do not insulate electrode thread with hemp or PTFE tape!
Do not apply conductive paste or grease to the electrode thread!
Observe the minimum withdrawal distance when installing the electrode!
Observe the specified tightening torque.
Do not cut the electrode rod.
Attention
NRG 26-21
1. Check seating surfaces.
Fig. 3
2. Place supplied joint ring
2
onto seating surface of the threaded standpipe or flange.
Fig. 3
3. Apply a light smear of heat resistant silicone grease(e.g. WINIX
®
2150) to electrode thread
3
.
4. Screw level electrode into threaded standpipe or flange and tighten with an open-end spanner
A. F. 41 mm. The torque required
when cold is 160 Nm.
Tools
Open-end spanner A. F. 41, DIN 3110, ISO 3318
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