Structural Design; Assembly - Installation; Minimum Air Gap In Compliance With The Material Combinations; Maximum Permissible Vibration Limits - Helios RD Serie Montage- Und Betriebsvorschrift

Installation and Operating Instructions
EN
CHAPTER 3
ASSEMBLY
m
ATTENTION
m
ATTENTION
RD..  and VD..  – Roof fans
3.0

Structural design

The RD/VD..Ex roof fans are directly driven fans with motors located directly in the air stream. The air flow direction is
through the motor (suction). The casings, support profiles and inlet nozzles are made from aluminium. The base plate
on the intake-side and the motor mount are made from galvanised sheet steel.
These types have a high performance impeller with aluminium blades. The dynamic balancing takes place according
to ISO 1940 T1, class 6,3. ATEX-certified motors pursuant to Directive 2014/34/EU (Equipment Safety Act) are used
as standard.
3.1 Assembly – Installation
All safety regulations must be observed during assembly and installation!
The fan is delivered in standard execution as a complete unit, i.e. ready for installation. Before delivery, every fan is
tested at the factory. After unpacking and before installation the following points should be checked::
– damages from transport.
– unhindered running of impeller.
– uniform distance from impeller (cover plate) and inlet nozzle (minimum air gap, see 3.2).
– The installation location must be suitable for the roof fan with regard to type, condition, ambient temperature and
ambient medium. The substructure must be level with sufficient load-bearing capacity.
– The roof fans are designed for base installation. There are 4 drill holes in the base plate of the fan for attachment to
the base. Place the fan with the base plate on the base (see accessories). In this respect, observe the respective
installation and operating instructions for the flat roof bases. Tighten the base screws evenly in order to prevent
warping.
– There must be a straight, flat pipe section or an unimpeded intake for the intake area. The discharge area must not
be blocked and a minimum distance of 1 m to the fan must be observed. The fan must be easily accessible for cle-
aning and maintenance purposes, particularly the terminal box/isolator switch.
– The casing must not be deformed or warped during installation (minimum air gap test, see 3.2).
3.2

Minimum air gap in compliance with the material combinations

Before installing check the minimum air gap between the impeller (cover plate) and the inlet nozzle according to the
following table:
Type
RDD/VDD 200/.. Ex
RDD/VDD 225/.. Ex
RDD/VDD 250/.. Ex
RDD/VDD 315/.. Ex
RDD/VDD 355/.. Ex
RDD/VDD 400/.. Ex
RDD/VDD 450/.. Ex
RDD/VDD 500/.. Ex
RDD/VDD 560/.. Ex
RDD/VDD 630/.. Ex
If the stated values
not be installed or operated. For questions, please contact the Helios customer service.
Own repair attempts are strictly prohibited!
3.3 Maximum permissible vibration limits according to ISO 14694 / ISO 10816-3
Commissioning
stationary mounted set up flexible
[mm/s] [mm/s]
4,5
3.4

Recommended tightening torque for mounting screws

The following tightening torques for connection of mounting nuts and screws (grade 8.8) are to be used:
Screw size
M10
3.5

Functional safety - Emergency operation

When using the roof fan in important technical supply function it must be installed in such a way that with fan failure
automatically an emergency operation is guaranteed. Suitable solutions are e.g.: Parallel operation of two devices of
lower performance with separated current supply, standby roof fan, alarm and emergency ventilation systems.
Minimum air gap
„S"
2 mm
2 mm
2 mm
2,4 mm
2,7 mm
3 mm
3,4 mm
3,8 mm
4,2 mm
4,8 mm
do not correspond to
max. permissible vibration limits for a fan power < 75 kW
Alarm
stationary mounted
[mm/s]
6,3 7,1
M8
4
Impeller (cover plate)
Laufrad (Deckscheibe)
Inlet nozzle
Düse
the specified dimensions,
Switching off
set up flexible stationary mounted
[mm/s] [mm/s]
11,8 9,0
Tightening torque
20 Nm
35 Nm
Fig.3
S
the fan may
set up flexible
[mm/s]
12,5