---

Where the minimum angle of installation (combining roof pitch and ventilator pitch) recommended by the supplier exceeds 45°, the ventilator takes the classification SL 1000 without a test; except where the snow will be prevented from slipping from the ventilator e.g. by wind deflectors.

If the ventilator is fitted with deflectors, the snow load classification shall not be less than SL=2000 d where d is the depth of snow, in metres, which can be contained with the confines of the deflectors.

NOTE The following types of ventilators may be suitable for use on heated buildings without a snow load classification test:

1. vertical discharge units without flaps or dampers;

2. vertical discharge units with uninsulated metal flaps or dampers.

A powered ventilator with a separate device for the operation of the dampers, flaps or louvres, which does not use the air pressure from the fan, shall conform to 7.3 of prEN 12101-2:1995, when tested in accordance with annex E of prEN 12101-2:1995.

A powered ventilator with dampers, flaps or louvres or a separate device for the operation of the dampers, flaps or louvres, which does not use the air pressure from the fan, shall conform to 7.1 of prEN 12101-2:1995 when tested in accordance with annex C of prEN 12101-2:1995.

NOTE It is permissible to convert these figures to determine the performance with hot gases and at other speeds of rotation using the scaling formulae from ISO 5801, with due allowance for tip clearance effects.

4. 2. If a ventilator is designed to be fitted with a duct for cooling air the data sheet shall include the volume pressure characteristic of the auxiliary system and the minimum cooling air flow required.

5. Marking

The ventilator shall be marked with the following:

1. the name or trade mark of the supplier, and

2. the type and model; and

3. the application classes; and

4. the temperature/time category; and

5. the maximum exhaust temperature in °С; and

6. the functioning period in minutes; and

7. the year of manufacture; and

8. technical data such as power, current, voltage, pressure, volume flow; and

9. the motor insulation class; and

10. the snow load class;

11. the number and the year of this European Standard.

Where the requirements of annex ZA.3 give the same information as above, the requirements of this clause (7) shall be considered to have been met.

4. Evaluation of conformity

   1. General

The compliance of powered smoke and heat exhaust ventilators with the requirements of this standard shall be demonstrated by:

• initial type testing,

• factory production control by the manufacturer.

Initial type testing shall be performed on first application of this standard. Tests previously performed in accordance with the provisions of this standard (e.g. same product, same characteristic(s), test method, sampling procedure, system of evaluation of conformity) may be taken into account. In addition, initial type testing shall be performed at the beginning of the production of a new product type or at the beginning of a new method of production (where these may affect the stated properties).

All characteristics given in clauses 5 and 6.1 to 6.7 shall be subject to initial type testing.

The manufacturer shall establish, document and maintain an FPC system to ensure that the products placed on the market conform with the stated performance characteristics. The FPC system shall consist of procedures, regular inspections and tests and/or assessments ana tne use of the results to control raw and other incoming materials or components, equipment, the production process and the product, and shall be sufficiently detailed to ensure that the conformity of the product is apparent.

An FPC system conforming with the requirements of the relevant part(s) of EN ISO 9000, and made specific to the requirements of this standard, shall be considered to satisfy the above requirements.

The results of inspections, tests or assessments requiring action shall be recorded, as shall be any action taken. The action to be taken when control values or criteria are not met shall be recorded.Annex A
(normative)

Type approval schedule for a range of ventilators

A.l Reduction of numbers of tests for ventilators forming a product range

For the purpose of type approval it is not usually considered necessary to test every size of ventilator in a product range provided that the following are tested and the range complies with the rules given in A.3 and A.4 and annex B:

1. the ventilator with the most highly stressed impeller, or the ventilators with impellers in which the individual stress in any material, weld or fastening is the highest, as appropriate (see A.4);

2. for ventilators with motors mounted in an enclosure which restricts the cooling, the worst case shall be tested, for example the ventilator with the ratio of motor cross sectional area to the minimum cross sectional area through which the cooling air flows;

3. at least two sizes are tested at their highest rotational speed;

4. the ventilator with the smallest motor frame size to be used;

5. if the highest impeller stress levels are determined by geometric similarity conditions from A.4.1, sufficient sizes of ventilators to ensure that the impeller diameters of the range are from 0,8 to 1,26 of those tested;

6. if the highest impeller stress levels are determined by the calculation methods in A.4.2, sufficient sizes of ventilators to ensure that the impeller diameters of the range are from 0,63 to 1,26 of those tested.

A.2 Motors

A product range shall only be approved if the motors used in the range are also approved, except when the impeller is not mounted on the motor shaft and the motors are out of the airstream in ambient air and the cooling of the motor is not affected by heat transfer from the ventilator or the ventilator construction. When the motor is out of the airstream and the impeller is mounted on the motor shaft, motors from a different supplier to the one used in the ventilator test may be used, provided that the tested and alternative motors are of the same construction, i.e. same class of insulation and bearing type and class of fit and same synchronous speed and rating.

A.3 Combined testing

The tests to approve ventilators and motors may be performed at the same time. The motor approval procedure is given in annexes В and D. Motors tested independently of fans or in another range of ventilators may also be used provided these tests have been undertaken with similar mechanical loads and cooling conditions as described in this annex and annex D.

A.4 Determination of highest stresses in impellers

A.4.1 Ventilators with geometrically similar impellers.

For geometrically similar impellers the impeller with the highest peripheral speed is the most highly stressed.

Impellers are geometrically similar if all dimensions, excluding thickness of materials, are within 5 % and the thickness of materials is within + 10 % of the values scaled by the ratio of the impeller diameters, and the numbers of blades and fastenings are identical. The centre boss is excluded from the geometric similarity requirements.

A.4.2 Ventilators with impellers that are not geometrically similar.

NOTE The method given for calculating stresses is for comparative purposes only and is not suitable for design assessment. It only takes into account centrifugally induced stresses as aerodynamically induced stresses are of less importance.

A.4.2.1 Axial impellers

A.4.2.1.1 Centrifugal force

Divide the blade into four parts using five sections as shown in Figure A.l.

Calculate the centrifugal force for each part as follows

Л,,., = f^(Лx- *.)')*/’*[ WaliSJ'jxa¹ ) X J

Where

E_n,_n+i is the centrifugal force in Newtons of the part of the blade between sections n and n+1;

p is the density in kg/m³;

A_n is the area of section n in m²;

R_n is the radius of section n;

a is the angular velocity in radians/s.

Figure A.l — Axial impeller, blade divided into four parts using five sections

Calculate the tensile stress as follows, see Figure A.2.

F_n= F_n,_n+1 + +^4Д

<T_Tn = F_nA_n/10⁶

Where

cr_Tn is the tensile stress in N/mm²;

n is the number of the section.

Figure A.2 — Axial impeller, application of centrifugal force

A.4.2.1.2 Fastenings or welds

Treat fastenings or welds as the inboard end of the blade section with the cross section area calculated from the weld or fastener area.

A.4.2.1.3 Hub/backplate/shroud stresses

Consider only forces due to centrifugal effects. The stresses on the hub are a combination of the self induced stress due to the rotation of the hub, the hoop stress due to the loads imposed by the blades, and the bending stress due to the point loads of the blades.

pxR_h²xa²

^CTsl " IO⁶

Where

cr_Si is the self induced stress in N/mm²;

7?h is the maximum hub radius in m;

a is the angular velocity in radians/s;

p is the density in kg/m³.

Assume that only the section of the hub/backplate/shroud approximately symmetrical about the plane of rotation through the centre of the blade fixing is supporting the blades, see Figure A.3, then calculate the hoop stress,

cr_h = ^_₅ / (2-3--A_h)

Where

cr_h is the hoop stress in N/mm²,

A is the number of blades,

Fi.₅ is the total blade centrifugal force in Newtons,

A_h is the cross sectional area of the hub in mm².

Calculate the section modulus about an axis through the section centre of area, parallel to the axis of rotation, using the distance to the outside of the hub/backplate/shroud supporting the blade. Then calculate the bending stress.

a-_b= CF^ 5 х2я-xR_h/(N x12xZ)

Where

Ob is the bending stress in N/mm²,

Z is the section modulus in mm³,

Then using linear hypothesis

Total stress = o-_si + Oh + Ob

I

Figure A.3 — Portion of hub to be used for calculation

NOTE Shaded parts show portion to be used for calculation.A.4.2.2 Centrifugal impellers

A.4.2.2.1 Centrifugal force

The centrifugal force is calculated by treating the blade as one piece, as follows

F = p x A_bx I x R xa²

Where

F is the centrifugal force in N,

p is the density of blade material in kg/m³,

Аь is the cross section area of the blade at the centre of gravity, perpendicular to the axis of rotation in m²,

1. is the distance between the backplate and shroud, through the centre of gravity, parallel to the axis of rotation, in m,

R is the radius of blade centre of gravity about the axis of rotation, in m,

a is the angular velocity of impeller in radians/s.

Figure A.4 — Centrifugal impeller, calculation of centrifugal forces about a principal
axis

A.4.2.2.2 Blade bending moment

M = Fxl/k

Where

M is the bending moment in №n

к is a constant depending on the type of impeller construction (for comparative purposes use к = 1).

A.4.2.2.3 Comparative blade stresses

To calculate comparative blade stresses resolve the bending moment about the principal axis and the stress calculated as follows:

Ob max ⁼ 1000 X А/ X COS 11 Z_max

Ob min = 1000 X M X sin I / Zmin

Where

Ob max is the bending stress about the maximum principal axis in N/mm²,

Ob min is the bending stress about the minimum principal axis in N/mm²,

1. is the angle between maximum principal axis and a radial line,

Z is the section modulus about principal axis in mm³.

A.4.2.2.4 Blade joint stress

Calculate the relative shear stresses at each blade joint as follows

cr_s = F/A

Where

cr_s is a shear stress in N/mm²,

A is the area of cross section of fastening at joint in mm²’

A.5 Assessment of changes after testing

A.5.1 Assessment of motor changes

If motors of a different construction or from a different a supplier to the one that has been tested are used , the assessment shall be made, in accordance with annex A.2, by the body responsible for testing the product range.

A.5.2 Assessment of detail changes

If detail changes are made to the product range that has been tested, the body responsible for testing the product range shall assess either that the changes do not worsen the performance of the product range or that further specific tests are necessary to verify performance.Annex В
(normative)

Type approval schedule for a product range of motors

For the purpose of type approval it is not usually considered necessary to test every size and speed of motor to be used in a range of powered ventilators. Provided tests are carried out on the largest and smallest motor frame size at the highest ratings it may be assumed that all the motors in a range will comply with the standard.

If the sponsor wishes to use motors of a different construction to the one that has been tested, the assessment shall be made in accordance to annex A.2, by the body responsible for testing the product range.

If detail changes are made to the product range that has been tested, the body responsible for testing the product range shall assess either that the changes do not worsen the performance of the product range or that further specific tests are necessary to verify performance.Annex C
(normative)

Test method for performance of powered ventilators at high temperature

C.l Principle

Determine the performance of powered ventilators by testing the ventilator so that at normal ambient pressure and temperature (i.e. density 1,2 kg/m³) the power output input is 80 % to 100 % of the maximum absorbed input power of the ventilator motor and it is operating anywhere on its volume pressure curve, provided the volume or pressure readings are stable.

C.2 Apparatus

C.2.1 Furnace, capable of heating the required quantity of air and raising the temperature of the system to the specified level in the specified time within the specified tolerances, either connected directly or through a system of ducting either to recirculate the hot gases or to discharge to atmosphere, see Figures C.l, C.2 and C.3.

NOTE Some test furnaces are specified in ISO 834 and ISO 6944.

Key

1 Furnace

2 Ventilator

Figure C.l — Ventilator connected directly to furnace

Key

1. Furnace

2. Ventilator

Figure C.2 — Ventilator connected to furnace by recirculating duct system

Key

1. Furnace

2. Ventilator

Figure C.3 — Ventilator mounted inside furnace

C.2.2 Flow and/or pressure measuring equipment in accordance with ISO 5801, EN ISO 5167 or ISO 5221 or static pressure taps, in accordance with ISO 5221, either side of the impeller.

C.2.3 Thermo-elements and thermocouples in accordance with EN 1366 and EN 1363.

C.3 Preparation

Set up the ventilator, following the supplier’s instructions, with its air-intake side connected to the furnace so that it represents as near as possible the conditions to which it will be exposed in service.

Test the ventilator by a method appropriate to the application class or classes (stated by the manufacturer). Set up a smoke reservoir ventilator either surrounded by hot gases as indicated on Figure C.3, or, if the motor is inside the fan totally surrounded by the high temperature gas flow and not cooled by ambient air, set up the ventilator insulated so that the effect is the same as being surrounded by hot gases. Install a non smoke reservoir ventilator connected to the hot gases either by partial insertion, e.g. for a roof extract unit, or in a ducted system surrounded by ambient air, see Figures C.l to C.3). It may be necessary to make special duct connections when hot gas recirculation test systems are used. Install the duct connection so that it does not prevent heat recirculation to the motor if this could happen in practice.

For the case when the ventilator discharges motor cooling air into the main airstream set up the ventilator so that the flow of cooling air is a minimum.

NOTE The flowrate will be affected by the operating point and the upstream and downstream loading.

Set up a flow or pressure measuring device in the system to measure the volume flow or pressure of the ventilator.

NOTE The installation of flow measuring devices or pressure taps is not critical as the readings are for comparative purposes only and cannot be used to indicate actual performance.

Test an insulated axial fan for use as an uninsulated fan as well as an insulated fan with a smaller than normal tip clearance. The reduction in tip clearance shall be calculated as follows:

Reduced clearance = normal clearance — reduction of clearanceReduction of clearance = (ZD/2). С.ЛТ mm

Where

D is the diameter at minimum clearance in mm;

C is the coefficient of expansion for the material of the casing;

AT is half the difference between the hot gas temperature and the ambient temperature.

Measure the minimum clearance between the impeller and the casing. Check that

1. it is not less than the minimum specified by the supplier;

2. it is not greater than the minimum plus 25 %.

NOTE A ventilator tested with insulation will have a higher casing temperature than one without insulation and consequently under test will have a larger tip clearance.

Fit at least three furnace thermo-elements at approximately 100 mm upstream of the intake plate of the ventilator, positioned uniformly, to measure the temperature of the incoming gases.

Where the motor is mounted within the fan casing and is cooled by ambient air, fit flow measuring equipment taking care that it does not affect the flowrate of cooling air. Also fit thermocouples in the centre of the inlet and exit airways.

Fit electrical devices for the measurement of frequency, voltage, current, power and speed in accordance with IEC 34-2. A frequency measurement is not required if the main supply is of known frequency.

C.4 Procedure

C.4.1 General conditions

Carry out the following tests, continuously in the order indicated, at an ambient temperature between 15 °С and 40 °С and in a location not affected by varying ambient conditions such as rain, snow, wind. Test insulated fans inside a building. Check that any cooling air is not below 15 °С. Start test measurements prior to the test period. For ventilator classes F200, F300, F400 an F600 test in accordance with C.4.2, C.4.3 and C.4.4. For ventilator Class F842 test in accordance with C.4.2 and C.4.5.

If a ventilator is tested at a higher temperature and for a longer period than a lower class or classes then the ventilator shall also be approved for that class or classes.

During the entire period of the test (for products intended to be installed within a building) observe the emissions of any smoke from the furnace coming from the housing of the ventilator due to distortion/leakage of the housing.

C.4.2 Warm up period

C.4.2.1 Do not operate an emergency ventilator prior to test. Operate a dual purpose ventilator at ambient temperature, at the maximum speed, for a warm up period until the motor carcase temperature increase is less than 2 °С in 10 minutes but for a minimum period of 60 min. Record voltage, current, power, flow or pressure and temperature measurements at intervals not exceeding 2 min. Ensure measurements are stable.

C.4.2.2 Operate an emergency ventilator at ambient temperature until the volume flow or pressure readings are stable.

NOTE A variation of +/-1 % in volume flow or +/- 2 % in pressure, averaged over consecutive 2 minute periods, may be considered stable.

C.4.3 Heat up period

Increase the gas temperature at the intake plane of the powered ventilator to the appropriate value specified in Table 1 in a period of not more than 10 min. and not less than 5 min. Record voltage, current, power, temperature and flow and/or pressure measurements.