Calculating heat dissipation in Eldon enclosures

1 Calculating heat dissipation in Eldon enclosuresVisit our website at | 32 | Calculating heat dissipation in Eldon enclosuresHeat is the main reason for electronic component failure inside an enclosure . The service life of these components is halved, and the failure rate is doubled in the event of a 10 K temperature increase relative to the maximum permitted operating with heat losses in enclosures depends on whether the enclosure is equipped with cooling accessories, like filter fans and cooling units, and whether the enclosure is supposed to be air tight.

2 For an enclosure that has cooling accessories installed, heat losses can be dissipated through active heat dissipation . If an enclosure has to remain closed without any cooling accessories, heat can only be dissipated through the enclosure most important factor in what type of heat transfer is possible is the maximum ambient temperature at the enclosure location and the maximum temperature inside the enclosure . The maximum temperature increase relative to the environment inside the enclosure can be determined from the following equation:(Ti-Tu) = Qv / (k*A) Where: Qv- Watts to dissipateTu- Ambient temperatureTi- Permitted internal temperaturek- heat transfer coefficientA- enclosure surface areaTo choose the most suited climate control solution for an enclosure , it is necessary to calculate the heat loss, Qv , in the enclosure .

3 The following parameters also need to be calculated. Qv - heat loss installed in the enclosure (W)Qs - Thermal radiation via enclosure surface Qs = k *A * TQk - Required useful cooling output (W) T - Temperature difference between inside and outside temperature (K) T = (Ti-Tu)Qe - Required cooling output (W) Qe = Qv - QsV - Required volumetric flow of fan and filter unit (m /h) Approximate calculation V = ( *Qv)/ TVisit our website at | 54 | Calculating heat dissipation in Eldon enclosuresThe maximum Internal enclosure temperature is determined by the electrical components used in the enclosure .

4 As far as the recommended internal enclosure temperature is concerned, an average value of +35 C has become the norm. In addition, the enclosure surface area must also be determined according to the installation :The tables below show the amount of heat that is dissipated (W) through the enclosure surface, when the T is 20K. The temperature difference between the ambient temperature and the maximum permitted internal temperature is then 20K: Ti (internal temperature) = 45 CTu (Ambient temperature) = 25 C T = (Ti-Tu) T = 45-25 T = 20 KExampleFree standing enclosure , MCS18044R5 Ti (internal temperature) = 50 C, Tu (Ambient temperature) = 40 C.

5 T = (Ti-Tu) T = 50-40 T = 10K enclosure heat dissipation value according to the table below (when T is 20K): 310W 310 / 20K = 15,5W 15,5 x 10K = 155 W If the T = 10K, the natural heat dissipation of a free standing MCS18044R5 is 155 WAll data is calculated by using the formulas presented in this you find that the natural heat dissipation presented in these lists is not enough for the enclosure application at hand, active cooling accessories may have to be installed in the enclosure . Such accessories could be filter fans, heat exchangers, or Vortex coolers.

6 Take the relevant information you have on your application and go to Eldon s website and the thermal software there to calculate cooling, heating, and control accessory installation type according to IEC 60 890 Single enclosure , free standing on all sides A= x H x (W+D) + x W x DSingle enclosure , for wall mounting A= x W x (H+D) + x H x DFirst or last enclosure in a suite, free-standing A= x D x (W+H) + x W x HFirst or last enclosure in a suite, for wall mounting A= x H x (W+D) + x W x DEnclosure within a suite, free standing A= W x H + x W x D + H x DEnclosure within a suite, for wall mounting A= x W x (H +D)

7 + H x DEnclosure within a suite, for wall mounting, covered roof surfaces A= x W x H + 0,7 x W x D + H x DThe following tables demonstrate the amount of heat that is dissipated through the enclosure data is calculated using formulas mentioned in this you need further assistance to determine your cooling, heating, and control accessory needs, please go to the Eldon website and use the Thermal software to help you with your climate calculation. Visit our website at | 76 | Calculating heat dissipation in Eldon enclosuresW ( T =20 K)EnclosureH (mm)W (mm)D (mm)

8 1234567 MCS18044R5180040040031027827824624621520 2 MCS18045R5180040050035232031228027224122 5 MCS18046R5180040060039336234631429826724 8 MCS18055R5180050050039535535531631627625 7 MCS18064R5180060040039334636231433028226 4 MCS18065R5180060050043839139935135931228 8 MCS18066R5180060060048343643638838834131 3 MCS18084R5180080040047741444538241435032 6 MCS18085R5180080050052546248542244638235 2 MCS18086R5180080060057351052546247841437 8 MCS18104R5180010004005614815294504974183 87 MCS18105R5180010005006125325724935324534 15 MCS18106R5180010006006635836155365684884 42 MCS20044R5200040040034130630627127123622 4 MCS20045R5200040050038735234330829926424 9 MCS20046R5200040060043339838034532729227 4 MCS20048R5200040080052448945441938434832 4 MCS20055R5200050050043539139134734730328 3 MCS20064R5200060040043338039834536331029 1 MCS20065R5200060050048242943838539434131 8 MCS20066R5200060060053147847842542537234 5 MCS20068R5200060080062857655850548843539 8 MCS20084R5200080040052445448941945438435 9 MCS20085R5200080050057650653246248841838 7 MCS20086R5200080060062855857650552345241 5 MCS20088R5200080080073266266259159152147 2

9 MCS20104R5200010004006165285814935464584 27 MCS20105R5200010005006715836275395834954 57 MCS20106R5200010006007266386735856205324 86 MCS20108R5200010008008367487666786956075 46 MCS22066R5220060060057852052046246240437 6 MCS22068R5220060080068462660654852947143 4 MCS22086R5220080060068460662654856849045 3 MCS22088R5220080080079671871864164156351 4W ( T =20 K)EnclosureH (mm)W (mm)D (mm)1234567 MCD18085R5180080050052546248542244638235 2 MCD18104R5180010004005614815294504974183 87 MCD18105R5180010005006125325724935324534 15 MCD18124R5180012004006445496125175814864 49 MCD18125R5180012005006986036595646195244 78 MCD18126R5180012006007526577056106575625 07 MCD18164R5180016004008116857806537486215 72 MCD20085R5200080050057650653246248841838 7 MCD20104R5200010004006165285814935464584 27 MCD20105R5200010005006715836275395834954 57 MCD20106R5200010006007266386735856205324 86 MCD20108R5200010008008367487666786956075 46 MCD20124R5200012004007086026725676375324 95

10 MCD20125R5200012005007666607226166785725 26 MCD20126R5200012006008247187716657186125 57 MCD20128R5200012008009408348697647996936 20 MCD20164R5200016004008917508557158206796 30 MCD20165R5200016005009558149117708677266 64 MCD20166R5200016006001019878966825913773 699 MCD22106R5220010006007896937316346735765 30 MCD22126R5220012006008957798377217796636 07 Floor Standing EnclosuresSteel Range | Mild Steel | Combinable, Single Door | MCSF loor Standing EnclosuresSteel Range | Mild Steel | Combinable, Double Door | MCDV isit our website at | 98 | Calculating heat dissipation in Eldon enclosuresW ( T =20 K)EnclosureH (mm)W (mm)D (mm)