DURAG D-R 290, Operating Manual

Page: 101 / 202

5 | Installation
D-R 290 101
The cables to terminal X10 are pre-wired by the factory for the measuring heads. The
practical connection to the measuring heads is then performed via a plug connector.
When connecting the conductors to the terminals, make absolutely sure you use the
relevant twisted pairs of the cable for the associated conductors (e.g. RS 485 A and B,
4..20mA + and –, relay 1 NC and COM, etc.)!
Close the supply unit and tighten the four (captive) screws.
In order to maintain protection type IP 66 (NEMA 4.4x) any cable glands that are not
used must be securely sealed using suitable plugs.
Installation of the purge air unit
A purge air unit (blower) is required for supplying the device with purge air.
Purge air units are used to reduce contamination of the outer optical faces and to pro­
vide thermal protection of the device against exhaust gases. Even at plants with a nat­
ural operational vacuum, a purge air unit is required, because the device may become
contaminated if the boiler is shut down, the suction intake fails or during start-up.
Selection of an installation location of the purge air unit (blower)
The following points must be observed when selecting the installation location:
Damage as a result of blocked intake openings / purge air hoses!
The inlet opening must not be blocked or covered over by deposits of leaves, sand,
dirt, snow or the like.
It can also make sense to guard against ingress by small animals and insects so as to
avoid them causing interruptions in the purge air supply
▶
Fit the intake air hose so that no water, dirt or dust can accumulate in the hose.
▶
See technical data (e.g. ambient temperature and protection type) – see the ap­
pendix!
●
The intake air must be as free of dust and as dry as possible.
●
The temperature of the intake air must be within the range -20 to +40°C.
●
Sufficient clear space must be available for filter replacement (see Fig. 9.12 , sec­
tion 9.3.7 Dimensional diagram purge air unit D-BL [
}
188] ).
●
A weather protection cover type D‑BL WSHN is available for outdoors installation
of the purge air unit.
The purge air unit can be attached to the rear wall using the 4 attachment holes (see
Fig. 9.12 upper illustration).
Arrangement and installation of the purge air unit
The purge air unit is mounted on a compact stainless steel baseplate (material
no. 1.4301) (see also 9.3.7 Dimensional diagram purge air unit D-BL [
}
188] ).
5.8
5.8.1
5.8.2