Comments. IS Code. Recent; Popular; Featured. IS – – Pallets for materials. Buy BIS IS (R) SPECIFICATION FOR CENTRIFUGAL FANS from SAI Global. Standard Air. Centrifugal fans for use in mines and hazardous atmospheres may requirt: additional requirements to be met, not covered by this standard.
|Published (Last):||25 June 2013|
|PDF File Size:||12.46 Mb|
|ePub File Size:||7.64 Mb|
|Price:||Free* [*Free Regsitration Required]|
Full text of “IS Centrifugal fans”
The value of r may be taken as 1 “4 for atmospheric air. As type test, this test should preferably be done immediately after the temperature-rise test.
A fan with protective electrical insulation may be of all-insulated construction or have either double insulation or reinforced insulation. Standard marked products are also continuously checked by BIS for conformity to that standard as a further safeguard. The method of measurement of the speed of fan shall be such that the speed of the fan is not appreci- ably affected.
Such fans shall be specially marked. Note — Nevertheless, fans made for other freque- ncies shall be considered to comply with the specifica- tion provided they do so in all other relevant respects. Note — The need for specifying limits of noise levels acoustical of the fans is recognized. This value shall fall within the range of specified tolerances. The test voltage shall be applied as follows: All metallic parts tan with it shall be protected from accidental contact.
Manaksanstha Common to all centrifhgal Telephone,,’Sales Office in Calcutta is at 5 Chowringhee Approach, P.
IS 4894: Centrifugal fans
The other limbs of the manometer shall be opened to the ambient atmosphere and the manometer reading cemtrifugal be taken as equal to the average static pressure in the airway. When the guards are in two pieces, positive locking arrangement to keep the two pieces together should be made. When the air flow, in cubic metres per hour, is numeri- cally less than 16 times the airway diameter in metres, then the coefficient of discharge shall be taken appropriate to the Reynolds number given in Table 2.
The guards shall be securely attached and shall be adequately rigid to resist accidental contact with the blades. For routine and acceptance tests, instruments of class index 2 may be used.
Intermediate values of d, may be obtained by linear interpolation. For Reynolds numbers of and above, the coeffi- cient of discharge is 0″ and will cover the majority of fan tests. The stray load loss is assumed to be percent of the shaft power. The handle or knob shall be so designed that it does not become loose in use.
The criterion of noise level may, therefore, be subject to an agreement between the manufac- turer and the purchaser. The fixed losses and copper losses shall be calculated in accordance with the details given in IS: In the case of indirectly driven fans, the electric motor shall centrifygal to the relevant Indian Standard, 1.
Centrifugal fans [ETD 5: Note — In this specification, the term ‘fan’ shall be used to mean centrifugal fan as supplied, without any addition to the inlet or outlet, except where such addition is specified.
Part 1 General requirements second revision.
Note — The trade name, voltage and the size of the fan shall be marked on associated regulator. If the number of defectives found in the first sample is less than the rejection number, take a second sample of size indicated in col 3; and if the total number of defectives in the first and second sample put together is less than the rejection number, accept the lot, otherwise not.
A recommended sampling plan is given in Table 3. This is also commonly known as wheel diameter.
IS – – Centrifugal fans | QuestIn
The copper losses shall be calculated on the corresponding current at the duty point of the fan. This revision has been undertaken to take into account the experience gained since then and to align some of the safety requirements with the provisions of IS: Capacitors shall comply with IS: The 484 may be composed of one or more layers of even wire or iiabric supported by a wire guard.
In the case of a double insulated fan, both basically insulated parts and live parts shall not be accessible to the standard test finger. In the case of inductance type regulator, it is essential that no portion of the inductive winding should remain permanently short-circuited in any of the running positions.