Silver bus bar carries 6000 Amps (1.6*150*25) Current. 0000001800 00000 n
And I understand that a 1/4 x 4 bar has greater surface area and cooling, and consequently higher current carrying capacity, than a 1/2 by 2 bar. Here in the USA and in the electroplating industry, the nice round number of 1000 Amps per square inch for open bus bar was universally accepted long before I entered the industry, and that was over 60 years ago :-) How can I calculate how much current can I send through a solid conductor? I need to reinstall some bus-bars in our factory. 1) What is the actual size of busbar I have to use in this case? For example: A DC busbar with 38000A current, 200 v dc Sincerely yours, A. Hi cousin Hojat. free & open in air. when submerged, even if the particular steel were a little lower in conductivity. A. Hi Virendra. However, Storm is suggesting to derate the AC by 30% for DC current meaning those two bars would be 700 and 875 amps. My name is drew and I would like to know if conductivity of copper buss bars degrades with the accumulation of green corrosion. That means I'd go with 100 Amps/sq.in. My own thumb rule, which was already a well established guideline at the plating equipment manufacturer I went to work for in 1967 is simply 1 square inch (645 square millimeters) of cross sectional area in the bus bars for every thousand amps you want to carry. Q. Hi. Note to readers: The internet is a giant one-room schoolhouse where you can "overhear" stuff and misapply it; I'm talking about copper bus bars carrying DC current in electrowinning operations; I'm not offering a general theory applicable to all electrical contact surfaces :-), Q. Hi Q. A 1/4" x 4" buss however is at 1250 amps. 0000001060 00000 n
In Electrorefining they typically use triangular busbars, where the header bars of the cathodes and anodes go across these busbars, and only touch the top edge of the triangle. To the degree that they suggest that copper can only carry 70 to 87 percent of what we know for a fact that it has safely and reliably carried in tens of thousands of plating and anodizing installations over 5 or more decades, I think it is they who need to go back to the drawing board :-). Aren't the connections coming out of the rectifier implying that four or five 6 x 100 mm bars are suggested? Obviously, this is a suggestion only applicable to submerged plating jigs, and not to be extrapolated that it's okay to figure steel as 10 percent of copper in all applications :-). Q. I made 200 amp switch with tin coated copper busbar. A. Hi, Naresh. Generally, the allowable temperature rise is fairly low and it doesn't do much good to design to a higher allowable temperature rise anyway -- because conductivity is inversely proportional to temperature. Don't forget to check the ampacity of the anode rod when you fix the cathode rod. 9H^Q_P4s25g]DhE=E{H }JSm1G=7B but after looking up your company, I don't think that's the case, and what you will read on this page may be misleading :-(. Your busing is 12% short of IDEAL calculations. 0000026542 00000 n
Ray. Ed. In any case, you obviously should minimize potential exposure to live circuits even though they are only 24 V, and people in the area should clearly understand the situation. A. Hi Shiva. I never considered that there would be a difference in ampacity for AC vs DC. I think you may need to retain an experienced electrician, electrical engineer, or plating consultant -- someone who has worked with this stuff and is familiar with the concepts being discussed. here length or long does not affect the current carrying capacity of the busbar. Huh? i. Ted That's a lot, and it would apply to each pole if they're both 100 m long. Q. Hi to all, I want to know all types of Copper bars Current calculations. 1.68 x 10-8 ohm-m x 100 m / (1600 mm2 x 1 m2 / 1,000,000 mm2), so: Thanks! A. Hi Drew. A quick study of their ampacity tables complicates the issue even more. 0000000016 00000 n
Would appreciate some help. So basically I will be making up the busbars myself with a whole lot of 3/8 bolts. But if you were to look at that contact surface through a powerful microscope, you would see that only very small peaks and very limited areas are actually touching. Calculate the 150 x 25 mm busbar current carrying capacity in all the above materials. g|G9=PMN]rB}
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I think that's the case with the triangular bus bars, which are intended to deliver a knife-edge (and therefore better) contact surface. %PDF-1.5
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0000037369 00000 n
Closely related historical postings, oldest first: Q. Hello all, Are all components at least 1/4" x 3/4"? You have entered an incorrect email address! I have always understood that the Rise in Celsius is the rise over ambient or resting temperature. 0000001317 00000 n
Thanks & Regards. 30E&J@1"+O'+=J 0000003445 00000 n
0000051896 00000 n
Back when I was in school it was R = E / I, today you probably hear it as R = V / A. I would, however, like to make a suggestion. Maximum current 400 A on 8 ~ 10 V DC. I can't exactly answer your inquiry, but think of this: when two flat surfaces of say 1" x 1" contact each other, we might say that the contact area is one square inch, and the DC ampacity of the joint is therefore 1000 Amps. I believe de-rate AC values around 30%. 0000007519 00000 n
They are connected to the plating tanks with solid copper bars. 0000034377 00000 n Cables are widely used in plating shops. The current carrying capacity is drastically reduced with even a very small amount of alloying materials. I understand resistivity of metals increases with temperature and that I can decrease resistance by increasing the cross section of the conductor, but how do I know at what temperature (resistivity) will the conductor arrive if I send a given current through it? 0000009080 00000 n Hi, Sujin. Sorry, I don't have any experience with carbon brushes, so you'll have to wait for input from others on that. Regards, P Marek. The surface roughening that may occur at the bend is not serious as long as it is only a surface condition. I visited a GE or Westinghouse bus bar plant decades ago where they hung bus bar vertically and dipped it 4"-6" deep into the plating solution to plate the ends. To me, I think it is under size since the current ampacity of it should be around 2600A (in AC, DC should be less). The number of sizes shown are not as extensive as those in the tables of AC ampacities, and there may be slight discrepancies between the ampacities shown here and those obtained by calculations derived from AC ampacities. Q. Hello, I need to know the calculation for DC bus bars Size for Copper and Aluminium. 1/4" x 3" bus bar is rated 750 Amps, not 1500 Amps, based on 1000 A/sq.in. 0000003969 00000 n Drew, "No-Ox-Id" Compound And if this loss of performance is enough to change or clean the buss bar. As R=rho*length/Cross-Sectional Area wouldn't there be a high amount of resistance near the joins due to the area being so small (as the contact is on top resulting in an edge contact, rather than contacting the entire cross-section at the end)? 0000003221 00000 n endstream endobj 55 0 obj<> endobj 57 0 obj<>/XObject<>/ProcSet[/PDF/Text/ImageC]>>>> endobj 58 0 obj[59 0 R 60 0 R 61 0 R 62 0 R] endobj 59 0 obj<> endobj 60 0 obj<> endobj 61 0 obj<> endobj 62 0 obj<> endobj 63 0 obj<> endobj 64 0 obj<> endobj 65 0 obj<> endobj 66 0 obj<> endobj 67 0 obj<> endobj 68 0 obj<>stream You need at least two, not one, 12 mm x 100 mm busbars, although most experienced installers would probably use four or five 6 mm x 100 mm bars instead. Thank you very much for your post.
The resistivity is 10.371 ohm circular mils/foot at 20C surface of the cable. Thank you in advance. It is enough dimension for new copper ? endstream endobj 31 0 obj << /Type /FontDescriptor /Ascent 1005 /CapHeight 734 /Descent -209 /Flags 32 /FontBBox [ -50 -207 1447 1000 ] /FontName /AAMONO+Verdana /ItalicAngle 0 /StemV 96 /XHeight 546 /FontFile2 57 0 R >> endobj 32 0 obj << /Type /FontDescriptor /Ascent 891 /CapHeight 656 /Descent -216 /Flags 34 /FontBBox [ -568 -307 2000 1007 ] /FontName /AAMOPA+TimesNewRoman /ItalicAngle 0 /StemV 94 /XHeight 0 /FontFile2 61 0 R >> endobj 33 0 obj << /Type /Font /Subtype /Type0 /BaseFont /AAMOMK+Cambria /Encoding /Identity-H /DescendantFonts [ 54 0 R ] /ToUnicode 30 0 R >> endobj 34 0 obj [ /ICCBased 59 0 R ] endobj 35 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 176 /Widths [ 250 0 0 0 0 0 0 0 333 333 500 0 250 0 250 278 500 500 500 500 500 500 500 500 500 500 0 0 0 0 0 0 0 722 0 667 722 611 556 0 722 333 0 0 611 889 0 0 556 0 667 556 611 0 0 944 0 0 0 0 0 0 0 0 0 444 500 444 500 444 333 500 500 278 0 500 278 778 500 500 500 500 333 389 278 500 0 0 500 500 444 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 400 ] /Encoding /WinAnsiEncoding /BaseFont /AAMOPA+TimesNewRoman /FontDescriptor 32 0 R >> endobj 36 0 obj << /Type /FontDescriptor /Ascent 1005 /CapHeight 734 /Descent -209 /Flags 96 /FontBBox [ -166 -208 1705 1000 ] /FontName /AAMONM+Verdana-BoldItalic /ItalicAngle -15 /StemV 184.396 /FontFile2 60 0 R >> endobj 37 0 obj 3600 endobj 38 0 obj << /Filter /FlateDecode /Length 37 0 R >> stream 0000011343 00000 n
A. Hi, Hitendra. I am long familiar with open bus bar systems which have no insulation at all, and which have been used for many decades in plating shops -- but I've also seen movement toward people no longer accepting open bus bar systems as being safe, especially as we get to higher voltages like 24 V. Welding cable sized at 1000 Amps/square inch can be used as an alternative to open bus bar, but doesn't fully address the issue of people working with live 24 v systems. 0n3p10*@cg,bz%A!A [I W5X7 Dv8@/}/hB+C 1CpE#'?fbo WJ endstream endobj 63 0 obj 240 endobj 26 0 obj << /Type /Page /Parent 21 0 R /Resources 27 0 R /Contents [ 38 0 R 40 0 R 42 0 R 44 0 R 46 0 R 48 0 R 50 0 R 53 0 R ] /MediaBox [ 0 0 612 792 ] /CropBox [ 0 0 612 792 ] /Rotate 0 >> endobj 27 0 obj << /ProcSet [ /PDF /Text /ImageC ] /Font << /TT1 33 0 R /TT3 28 0 R /TT5 29 0 R /TT7 35 0 R >> /XObject << /Im1 51 0 R >> /ExtGState << /GS1 58 0 R >> /ColorSpace << /Cs6 34 0 R >> >> endobj 28 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 89 /Widths [ 342 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 711 711 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 776 762 724 0 683 650 0 0 546 0 0 637 948 847 850 733 0 782 710 682 812 0 0 0 737 ] /Encoding /WinAnsiEncoding /BaseFont /AAMONM+Verdana-BoldItalic /FontDescriptor 36 0 R >> endobj 29 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 176 /Widths [ 352 0 0 0 0 0 0 0 454 454 636 0 364 454 364 454 636 636 636 636 636 636 636 636 636 0 454 0 0 0 0 0 0 684 0 698 771 632 575 0 751 421 0 693 0 0 0 0 0 0 0 0 616 0 0 0 0 0 0 0 0 0 0 0 0 601 623 521 623 596 352 623 633 274 0 592 274 973 633 607 623 623 427 521 394 633 592 818 592 592 525 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 542 ] /Encoding /WinAnsiEncoding /BaseFont /AAMONO+Verdana /FontDescriptor 31 0 R >> endobj 30 0 obj << /Filter /FlateDecode /Length 214 >> stream Q. The minimum bend radii may be reduced only if specifically allowed by the conductor manufacturer. Yes, exactly. 0000014459 00000 n Thanks again, Kurt. This will work, and it should be done immediately before you risk catching the tank liner on fire.
0000005026 00000 n Also do you have an example of how long peak would be measured using your calculations? The minimum bending radius for aluminum is equal to twice the thickness of the bar. There are too heavy and dirty. That is, we have a macro thumb-rule that a square inch of copper can carry 1000 Amps, and we don't apply that macro rule to a micro situation. @ |Kj ;!EGK#&0l"W^Ui0o?wYlnd)Ffvk3mm3;0UE$00b-+fBf[ mKnw'k1Ke/e{SE(Y9k>.VE/xqEaBIM}y7:7"{88Q(Q.PrC(!y$-?^DR 0000014437 00000 n 0000001147 00000 n %PDF-1.3 % 24 0 obj << /Linearized 1 /O 26 /H [ 1240 353 ] /L 177436 /E 115625 /N 4 /T 176838 >> endobj xref 24 40 0000000016 00000 n Old bus bars are 52 x 14 mm (installed maybe 40 years ago). Maybe more heat transfer area to keep it cool. 0000020501 00000 n You can choose the type of busbar, either aluminium or copper or galvanized bars or iron busbar or silver in the results. And also I want Aluminum Calculations also. But please keep the discussion moving forward by trying your very best to phrase ongoing questions in terms of the answers that have already been offered. xb```b``vc`e` |@QYAUVMom;xvPZk'm\2k`` AE+20EXN[AyR~`?e?k1@U ' Q. Hello dear Ted, All joints (male/female ) are firm and good contact. Hope this helps. DC currents have no inductance; inductance is the voltage induced rather by a non-steady-state current. Good day Mihai. (your purchases make finishing.com possible). 2) How to calculate for DC busbar? So, how about if Im using trips 10mm wide, 40mm long and 2mm tick? R = 1.05 x 10-3 Ω You can measure the amperage along the length of the cathode bar on each rack/fixture with a tong tester/ammeter to verify the amperage is consistent. startxref 2. My opinion, and that's all it is, is that you should have ordered 6 mm x 52 mm (1/4" x 2") bars. The KVA waste sounds like 2000 A x 2.1 V /1000 = 4.2 KVA. 0000001854 00000 n 0000017398 00000 n =(3.ye!|q& B/PxX The length of the run is not totally irrelevant, but for typical plating shop runs, like 10.5 m, it's not real important. But I have not found a chart stating whether that is AC or DC. in has proven itself for decades. Steel is an alloy, and the conductivity of alloys varies very widely, with some stainless steels being only 3 percent as conductive as copper, and some plains steels close to 15 percent, so it's hard to put a perfect number on this. Now I have a rectifier which the rating the output rating is 12VDC, 4000A. 0000008590 00000 n 0000004455 00000 n How would you calculate the length and hole spacing required for a 2000A busbar at 48VDC if using 1/2" x 4" busbar? 0000001593 00000 n I think that we can see from Ohm's Law that the knife-edge contact is not causing a significant resistance, and we can see (with a thermal scanner if not by hand) that there is no dangerous heat buildup at the knife edge. Apex Tool Group - York, Pennsylvania USA, (your purchases make finishing.com possible). Q. There should be no decline. In same current, copper which apply to DC circuit should be larger than AC 50Hz circuit? 0000023480 00000 n In other words, how large does the cross section of the steel fixture have to be in to facilitate proper current flow or at least so that it does not overheat and fail mechanically. 0000008406 00000 n 0000001362 00000 n 3) Will the size be different for DC and AC 50 Hz? Welding cable is often used because it's both flexible and designed to carry substantial currents.
Good luck. Q. Hi, just wondering whether anyone can help decide proper size of a conductor. A. Hi, Suresh. A. Currently, bussing is only connected to one end of tank. A metal tool accidentally shorting out a 15,000 Amp power supply can be a spectacular event! Is cable advisable to use for 700 Amps Oil Cooled rectifier for Nickel plating or it should be Copper bar only. Distance from rectifier to tank is 10.5 m.
I want to measure the end resistance and inductance of a bus bar. %%EOF How to size this stuff has been explained numerous times just on this one thread alone, and if you can't follow it sufficiently to do the arithmetic yourself, you don't understand enough to install bus bar without guidance. 0000001608 00000 n Although voltage drop is proportional to the length of the bus bar, it's not conventional to use different cross-sections of bus bar for lengths of 6 meters vs 1 meter. Which methods I can apply to do the same. My question was very simple: Length here absolutely doesnt make any difference when comes to calculations?
0000003864 00000 n 0000004684 00000 n 0000003825 00000 n resistance specific dc formula wire physics conductor current solving volume circuits electric But figure it is about 10 percent of copper. DC causes greater heating of the bus. A. Hi Mike. Thank You. 0000000776 00000 n if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'electrical4u_net-banner-1','ezslot_11',126,'0','0'])};if(typeof __ez_fad_position != 'undefined'){__ez_fad_position('div-gpt-ad-electrical4u_net-banner-1-0')}; Very useful information, but confusing one thing It says that to calculate amps need to know only width and thickness (in my case copper strips). Yes. Thanks and Warm Regards As you see, we appended your inquiry to a thread which I think will answer it for you: the copper needs 1 inch of cross sectional area for every 1000 amps. If you are seeking a product or service related to metal finishing, please check these Directories: Jobshops The resistivity of copper bus bar is about 1.68 x 10-8 ohm-m, so I get as the resistance of your bus bar: Parts are hung in the tank using steel fixtures with copper strips to aid the current flow as far as it is possible. 0000008826 00000 n Safety issues are tricky at best.
A. Hi, Petr. I cannot reuse them and I don't want to. When we do inside diameters or fixtures that require a threaded bar, we use steel to support the mass of the part(s). Hb```f`` P @Qk&00L&,>Ib1O@Ae7N+S.k:Y$l6P0v The spacing between bars is equal to or more than their thickness, and the bars are run in a horizontal plane.
To me, that's the end of the analysis, the ampacity of the contact is based on the cross sectional area of the bus bar or the header bar, whichever is smaller. I currently have 1/4" x 3" Buss bar on my tanks, which according to the charts, is rated at 1500 amps at a 65 degree Celsius rise? 0000011129 00000 n According to my method, your 14 mm x 6 mm bar can carry 130 Amps in open air. I will appreciate any help you can provide. Some electrical people I talk to say DC current is like water, so that you can use the entire cross-section of the triangle as it is like spilling into a tank, but what about the other end? A. Hello again, Petr. ; J Sorry that it's hard to be of much more help from such a distance. My question are: 3bi50PK k`eiWj. trailer But the fact is, 1000 Amps/sq. Save my name, email, and website in this browser for the next time I comment. I've already offered my opinion on cables and the sizing criteria I use twice on this page; maybe someone will offer a second opinion. Thanks. plating on plastics - New Delhi, India. Ampacity rating to be used when the long axis of the bars is in the horizontal plane, or when the spacing between bars is less than the thickness of the bars, or when the bars are run in a vertical direction. I think that page should be fine for AC current calculations. But in my own experience, plating shops rarely use plated ends or buss bar clamps: they just drill holes, and wire brush No-Ox-Id compound onto the joint area before bolting together. 0000012813 00000 n CDA would encourage the reader to use the more conservative of the two figures, if there is a discrepancy. Q. I have seen plating shops clear coat or lacquer their bus bar runs (except for the connections of course) and it does seem to hold up well and to look better than streaky green stained copper. L = E / (dI/dt). Our maintenance people make the fixtures, but sometimes they are not sized properly so they overheat and parts end up at the bottom of the tank. Khor, for an electroplating bussing installation I would consider the ampacity of a 12 mm x 100 mm busbar (slightly under 1/2" x slightly under 4") to be about 1860 Amps. We use rectifiers that generally operate 7-9 V and about 1500-2000 A.
This would be for a DC combiner with a positive and negative bus to combine lithium battery banks and which would be the common point to power a whole lot of 48V inverters as a large energy storage system/UPS. Fits your number perfectly. Although it's true that the insulation may make them get somewhat warmer than an open bus bar, I've never personally seen a problem if the old thumbrule of one square inch per 1000 amps of rectifier capacity is used. and as stated above it's in line with 1000 Amp/sq.in. 0000002904 00000 n 0000011365 00000 n 0000002933 00000 n Did you wire brush the joints and apply conductive joint compound? So you will see that empirical numbers are used instead. The copper bus bar is ETP-110 100% IACS (International Annealed Copper Standard) conductivity (0.15328 ohm-gram/square meter) per ASTM B187. My amperage requirement is only 1500A, but I've overspec'd for heat, losses etc in the system. Q. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. Q. Hi Ted. I have had a hard time finding information regarding this. 0000070357 00000 n I have a question for you: what's the whole voltage drop, cross section and short circuit current computing procedure of a DC busbar? For DC bussing for a rectifier, however, I think the standard number used for decades, 1000 amps/square inch for open air bussing, is an easier and safer approach. I am not an electrical person, a mechanical person and it would seem to me to be a fundamental electrical problem, yet I cannot find any information anywhere. 0000001572 00000 n Are you sure the copper is all hard drawn electrolytically pure?
Best Regards Q. Q. I am looking into the ratings for the Bus bar that is used on my anodizing tanks.
Consult'g, Train'g& Software, About/Contact-Privacy Policy-1995-2022 finishing.com, Pine Beach, New Jersey, USA, -- this entry appended to this thread by editor in lieu of spawning a duplicative thread, Plating shop owner - Vsetin, Czech Republic, product designer - hyderabad, A.P., India, Transformers - Mumbai, Maharashtra, India. Thank you, A. Hi Khaled. After calculating voltage drop (V 10.2, please correct me if I'm wrong) the loss in voltage first will result in not getting required voltage at the bus end and heat dissipation will be high (about 20.4 KVA again correct me if I'm wrong) even if I adjusted the source voltage to compensate for the voltage drop the heat is high. Good afternoon. Good luck. And would it make any difference if use cables instead of copper bars. Good Morning Affiliate Link 0000012868 00000 n I have a follow up please, what about fixtures for hanging the parts in the tank? Ceiling Fan Power Consumption Calculation, Power Saving Tips, What is Busbar Current Carrying Capacity Calculation 5 Types of Busbar, AP Electricity Bill Calculator & Rate Per unit Cost 2022, Karnataka Bescom electricity bill calculator & Latest Tariff 2022, DHBVN Electricity Calculator & Per Unit Rate DHBVN, IDMT Tripping Time Calculator, Formula, Calculation, Battery Life Calculator, Formula, Example, Formula, Torque conversion Calculation, Formula, Example, T-Match Impedance Matching Calculation, Formula, Example, Strip line Trace Width Calculation, Formula, Example, Circular Waveguide Calculation, Formula, Example, VSWR Return Loss Calculation, Formula, Example, Trace resistance Calculation, Formula, Example, Tank circuit resonance Calculation, Formula, Example, T-Pad Attenuator Calculation, Formula, Example, Skin Depth Calculator, Calculation With Example, ITI Electrician Whatsapp Group Links Join, 1500+ Active Electrical Engineering WhatsApp Group Links Join, Top 10 Electrical Website for Electrical Engineering Students, Copper bar carries 4500Amps (1.2 x 150 x 25) current, Aluminium Carries 3000 Amps (0.8 x 150 x 25) Current, GI Bus Bar Carries 2250 Amps (0.6*150*25) Current. Q. For example, For 1500 Amps Which size Copper Bars I have to use Terminal box i.e. Is this a manually operated installation? 0000001240 00000 n 0000005512 00000 n I have been going back and forwards with this for weeks. 1. And V = I x R, so I get: 0000083756 00000 n 0000001485 00000 n The following tables have been provided by the Alliance for Telecommunications Industry Solutions (ATIS), T1 Committee, and represent ampacities for busbar sizes and arrangements typically found in the telecommunications industry. If you didn't understand something and want clarification, that's fine -- people will try explaining it in different words but few readers will even read let alone try to answer a question that was already answered and is then simply repeated :-). If these charts indicated higher ampacity than the simple old-fashioned method, I'd want to go along with them. The rectifier terminal often implies what size bus bar the rectifier manufacturer feels is appropriate. I dont think the busbars are sufficient to carry that current but these are the standard busbars they send to everyone?? Please advise.
Are these results based on peak current capability or sustained current capability? Using my current bussing, what are my limits on DC Amperage, and what is the temperature rise above ambient that I should factor in? .Xk6s(s$~h$H% Q. DC resistance of copper bus bar. There response was: I think the correct answer will be slightly more than 1/10 of a square inch for a peak load for only one second, but I can't say for sure, and feel that the codes probably want you to size things based on maximum-ever loads for safety, not usual loads. HTPn0Stt4$>v@$@FGq++N:d3 2m8w4zh!/iD0z'!/H-XYOpB]j QJ{Awu47]V|Yrx1-8oY-` j` If you wish to purchase a copy of the complete Standard, please visit the ATIS Document Center. e.g. Z ig[c7y6tl6 Q"*&}w ]BSA!(jB%[3HRe0%>C\~KyIwz[ q54fZ=6a7fv.ES:ElG5v_1*bTc1N1VI5McnlRI36VN46jehA Nn~Od[JnMqQ-cp_XdcJr,Ri}v9l/)fohp:=?H'L}NxT Fp0ZF0T=T&Cnq3~*Bg8Q):NTwO e?=P'Iti`=);F&!x}6~! The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful. Will connecting both ends of the cathode bar decrease the resistance through the cathode bar to the 40 plating racks evenly spaced on the bar? My existing plating tanks have undersized cathode bars (3"x .75", 4000A rectifier) which cannot be upsized. R6td&jPj kT4y. Hopefully someone who knows will help us. No abstract questions. Regards. This is specifically regarding hard chrome plating but can be applied to other types of plating as well. The ampacities that follow are from Table 5 of Standard T1.311, and are reproduced here solely for the convenience of the viewer. Thanks, A. 0000017420 00000 n I am building a LiFePO4 battery with 280aH cell (8s configuration 24V) and they sent me tinned clad busbar (copper inside) of 2mm thick and 20mm wide by 90 mm length ( I know length does not matter). 0000070279 00000 n Architecural Manufacturers & Distributors, Architectural Installation Contractors Database, UNS Standard Designation for Wrought and Cast Copper, ASTM Standard Designation for Wrought and Cast Copper and Copper Alloys, European Numbering System for Non-Ferrous Metals, The U.S. Copper Industry: Critical to Keeping the U.S. Q. Sorry, but we'd just run in circles and never get anywhere if, after 30 postings on a subject, instead of asking for specific clarifications people just say "start over and tell me everything" :-). 0000000998 00000 n xref cVVO.eU&D$?/m^N^]7m^zc :eXwd#i KD-NPhds"`%\GlU1^Z%lF{ Cl,al9IR2 3rRpp vwgW:_o@y e^[b[E5r'b?k1?
They are connected to the plating tanks with solid copper bars. 0000034377 00000 n Cables are widely used in plating shops. The current carrying capacity is drastically reduced with even a very small amount of alloying materials. I understand resistivity of metals increases with temperature and that I can decrease resistance by increasing the cross section of the conductor, but how do I know at what temperature (resistivity) will the conductor arrive if I send a given current through it? 0000009080 00000 n Hi, Sujin. Sorry, I don't have any experience with carbon brushes, so you'll have to wait for input from others on that. Regards, P Marek. The surface roughening that may occur at the bend is not serious as long as it is only a surface condition. I visited a GE or Westinghouse bus bar plant decades ago where they hung bus bar vertically and dipped it 4"-6" deep into the plating solution to plate the ends. To me, I think it is under size since the current ampacity of it should be around 2600A (in AC, DC should be less). The number of sizes shown are not as extensive as those in the tables of AC ampacities, and there may be slight discrepancies between the ampacities shown here and those obtained by calculations derived from AC ampacities. Q. Hello, I need to know the calculation for DC bus bars Size for Copper and Aluminium. 1/4" x 3" bus bar is rated 750 Amps, not 1500 Amps, based on 1000 A/sq.in. 0000003969 00000 n Drew, "No-Ox-Id" Compound And if this loss of performance is enough to change or clean the buss bar. As R=rho*length/Cross-Sectional Area wouldn't there be a high amount of resistance near the joins due to the area being so small (as the contact is on top resulting in an edge contact, rather than contacting the entire cross-section at the end)? 0000003221 00000 n endstream endobj 55 0 obj<> endobj 57 0 obj<>/XObject<>/ProcSet[/PDF/Text/ImageC]>>>> endobj 58 0 obj[59 0 R 60 0 R 61 0 R 62 0 R] endobj 59 0 obj<> endobj 60 0 obj<> endobj 61 0 obj<> endobj 62 0 obj<> endobj 63 0 obj<> endobj 64 0 obj<> endobj 65 0 obj<> endobj 66 0 obj<> endobj 67 0 obj<> endobj 68 0 obj<>stream You need at least two, not one, 12 mm x 100 mm busbars, although most experienced installers would probably use four or five 6 mm x 100 mm bars instead. Thank you very much for your post.
The resistivity is 10.371 ohm circular mils/foot at 20C surface of the cable. Thank you in advance. It is enough dimension for new copper ? endstream endobj 31 0 obj << /Type /FontDescriptor /Ascent 1005 /CapHeight 734 /Descent -209 /Flags 32 /FontBBox [ -50 -207 1447 1000 ] /FontName /AAMONO+Verdana /ItalicAngle 0 /StemV 96 /XHeight 546 /FontFile2 57 0 R >> endobj 32 0 obj << /Type /FontDescriptor /Ascent 891 /CapHeight 656 /Descent -216 /Flags 34 /FontBBox [ -568 -307 2000 1007 ] /FontName /AAMOPA+TimesNewRoman /ItalicAngle 0 /StemV 94 /XHeight 0 /FontFile2 61 0 R >> endobj 33 0 obj << /Type /Font /Subtype /Type0 /BaseFont /AAMOMK+Cambria /Encoding /Identity-H /DescendantFonts [ 54 0 R ] /ToUnicode 30 0 R >> endobj 34 0 obj [ /ICCBased 59 0 R ] endobj 35 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 176 /Widths [ 250 0 0 0 0 0 0 0 333 333 500 0 250 0 250 278 500 500 500 500 500 500 500 500 500 500 0 0 0 0 0 0 0 722 0 667 722 611 556 0 722 333 0 0 611 889 0 0 556 0 667 556 611 0 0 944 0 0 0 0 0 0 0 0 0 444 500 444 500 444 333 500 500 278 0 500 278 778 500 500 500 500 333 389 278 500 0 0 500 500 444 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 400 ] /Encoding /WinAnsiEncoding /BaseFont /AAMOPA+TimesNewRoman /FontDescriptor 32 0 R >> endobj 36 0 obj << /Type /FontDescriptor /Ascent 1005 /CapHeight 734 /Descent -209 /Flags 96 /FontBBox [ -166 -208 1705 1000 ] /FontName /AAMONM+Verdana-BoldItalic /ItalicAngle -15 /StemV 184.396 /FontFile2 60 0 R >> endobj 37 0 obj 3600 endobj 38 0 obj << /Filter /FlateDecode /Length 37 0 R >> stream 0000011343 00000 n
A. Hi, Hitendra. I am long familiar with open bus bar systems which have no insulation at all, and which have been used for many decades in plating shops -- but I've also seen movement toward people no longer accepting open bus bar systems as being safe, especially as we get to higher voltages like 24 V. Welding cable sized at 1000 Amps/square inch can be used as an alternative to open bus bar, but doesn't fully address the issue of people working with live 24 v systems. 0n3p10*@cg,bz%A!A [I W5X7 Dv8@/}/hB+C 1CpE#'?fbo WJ endstream endobj 63 0 obj 240 endobj 26 0 obj << /Type /Page /Parent 21 0 R /Resources 27 0 R /Contents [ 38 0 R 40 0 R 42 0 R 44 0 R 46 0 R 48 0 R 50 0 R 53 0 R ] /MediaBox [ 0 0 612 792 ] /CropBox [ 0 0 612 792 ] /Rotate 0 >> endobj 27 0 obj << /ProcSet [ /PDF /Text /ImageC ] /Font << /TT1 33 0 R /TT3 28 0 R /TT5 29 0 R /TT7 35 0 R >> /XObject << /Im1 51 0 R >> /ExtGState << /GS1 58 0 R >> /ColorSpace << /Cs6 34 0 R >> >> endobj 28 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 89 /Widths [ 342 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 711 711 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 776 762 724 0 683 650 0 0 546 0 0 637 948 847 850 733 0 782 710 682 812 0 0 0 737 ] /Encoding /WinAnsiEncoding /BaseFont /AAMONM+Verdana-BoldItalic /FontDescriptor 36 0 R >> endobj 29 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 176 /Widths [ 352 0 0 0 0 0 0 0 454 454 636 0 364 454 364 454 636 636 636 636 636 636 636 636 636 0 454 0 0 0 0 0 0 684 0 698 771 632 575 0 751 421 0 693 0 0 0 0 0 0 0 0 616 0 0 0 0 0 0 0 0 0 0 0 0 601 623 521 623 596 352 623 633 274 0 592 274 973 633 607 623 623 427 521 394 633 592 818 592 592 525 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 542 ] /Encoding /WinAnsiEncoding /BaseFont /AAMONO+Verdana /FontDescriptor 31 0 R >> endobj 30 0 obj << /Filter /FlateDecode /Length 214 >> stream Q. The minimum bend radii may be reduced only if specifically allowed by the conductor manufacturer. Yes, exactly. 0000014459 00000 n Thanks again, Kurt. This will work, and it should be done immediately before you risk catching the tank liner on fire.
0000005026 00000 n Also do you have an example of how long peak would be measured using your calculations? The minimum bending radius for aluminum is equal to twice the thickness of the bar. There are too heavy and dirty. That is, we have a macro thumb-rule that a square inch of copper can carry 1000 Amps, and we don't apply that macro rule to a micro situation. @ |Kj ;!EGK#&0l"W^Ui0o?wYlnd)Ffvk3mm3;0UE$00b-+fBf[ mKnw'k1Ke/e{SE(Y9k>.VE/xqEaBIM}y7:7"{88Q(Q.PrC(!y$-?^DR 0000014437 00000 n 0000001147 00000 n %PDF-1.3 % 24 0 obj << /Linearized 1 /O 26 /H [ 1240 353 ] /L 177436 /E 115625 /N 4 /T 176838 >> endobj xref 24 40 0000000016 00000 n Old bus bars are 52 x 14 mm (installed maybe 40 years ago). Maybe more heat transfer area to keep it cool. 0000020501 00000 n You can choose the type of busbar, either aluminium or copper or galvanized bars or iron busbar or silver in the results. And also I want Aluminum Calculations also. But please keep the discussion moving forward by trying your very best to phrase ongoing questions in terms of the answers that have already been offered. xb```b``vc`e` |@QYAUVMom;xvPZk'm\2k`` AE+20EXN[AyR~`?e?k1@U ' Q. Hello dear Ted, All joints (male/female ) are firm and good contact. Hope this helps. DC currents have no inductance; inductance is the voltage induced rather by a non-steady-state current. Good day Mihai. (your purchases make finishing.com possible). 2) How to calculate for DC busbar? So, how about if Im using trips 10mm wide, 40mm long and 2mm tick? R = 1.05 x 10-3 Ω You can measure the amperage along the length of the cathode bar on each rack/fixture with a tong tester/ammeter to verify the amperage is consistent. startxref 2. My opinion, and that's all it is, is that you should have ordered 6 mm x 52 mm (1/4" x 2") bars. The KVA waste sounds like 2000 A x 2.1 V /1000 = 4.2 KVA. 0000001854 00000 n 0000017398 00000 n =(3.ye!|q& B/PxX The length of the run is not totally irrelevant, but for typical plating shop runs, like 10.5 m, it's not real important. But I have not found a chart stating whether that is AC or DC. in has proven itself for decades. Steel is an alloy, and the conductivity of alloys varies very widely, with some stainless steels being only 3 percent as conductive as copper, and some plains steels close to 15 percent, so it's hard to put a perfect number on this. Now I have a rectifier which the rating the output rating is 12VDC, 4000A. 0000008590 00000 n 0000004455 00000 n How would you calculate the length and hole spacing required for a 2000A busbar at 48VDC if using 1/2" x 4" busbar? 0000001593 00000 n I think that we can see from Ohm's Law that the knife-edge contact is not causing a significant resistance, and we can see (with a thermal scanner if not by hand) that there is no dangerous heat buildup at the knife edge. Apex Tool Group - York, Pennsylvania USA, (your purchases make finishing.com possible). Q. There should be no decline. In same current, copper which apply to DC circuit should be larger than AC 50Hz circuit? 0000023480 00000 n In other words, how large does the cross section of the steel fixture have to be in to facilitate proper current flow or at least so that it does not overheat and fail mechanically. 0000008406 00000 n 0000001362 00000 n 3) Will the size be different for DC and AC 50 Hz? Welding cable is often used because it's both flexible and designed to carry substantial currents.
Good luck. Q. Hi, just wondering whether anyone can help decide proper size of a conductor. A. Hi, Suresh. A. Currently, bussing is only connected to one end of tank. A metal tool accidentally shorting out a 15,000 Amp power supply can be a spectacular event! Is cable advisable to use for 700 Amps Oil Cooled rectifier for Nickel plating or it should be Copper bar only. Distance from rectifier to tank is 10.5 m.
I want to measure the end resistance and inductance of a bus bar. %%EOF How to size this stuff has been explained numerous times just on this one thread alone, and if you can't follow it sufficiently to do the arithmetic yourself, you don't understand enough to install bus bar without guidance. 0000001608 00000 n Although voltage drop is proportional to the length of the bus bar, it's not conventional to use different cross-sections of bus bar for lengths of 6 meters vs 1 meter. Which methods I can apply to do the same. My question was very simple: Length here absolutely doesnt make any difference when comes to calculations?
0000003864 00000 n 0000004684 00000 n 0000003825 00000 n resistance specific dc formula wire physics conductor current solving volume circuits electric But figure it is about 10 percent of copper. DC causes greater heating of the bus. A. Hi Mike. Thank You. 0000000776 00000 n if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'electrical4u_net-banner-1','ezslot_11',126,'0','0'])};if(typeof __ez_fad_position != 'undefined'){__ez_fad_position('div-gpt-ad-electrical4u_net-banner-1-0')}; Very useful information, but confusing one thing It says that to calculate amps need to know only width and thickness (in my case copper strips). Yes. Thanks and Warm Regards As you see, we appended your inquiry to a thread which I think will answer it for you: the copper needs 1 inch of cross sectional area for every 1000 amps. If you are seeking a product or service related to metal finishing, please check these Directories: Jobshops The resistivity of copper bus bar is about 1.68 x 10-8 ohm-m, so I get as the resistance of your bus bar: Parts are hung in the tank using steel fixtures with copper strips to aid the current flow as far as it is possible. 0000008826 00000 n Safety issues are tricky at best.
A. Hi, Petr. I cannot reuse them and I don't want to. When we do inside diameters or fixtures that require a threaded bar, we use steel to support the mass of the part(s). Hb```f`` P @Qk&00L&,>Ib1O@Ae7N+S.k:Y$l6P0v The spacing between bars is equal to or more than their thickness, and the bars are run in a horizontal plane.
To me, that's the end of the analysis, the ampacity of the contact is based on the cross sectional area of the bus bar or the header bar, whichever is smaller. I currently have 1/4" x 3" Buss bar on my tanks, which according to the charts, is rated at 1500 amps at a 65 degree Celsius rise? 0000011129 00000 n According to my method, your 14 mm x 6 mm bar can carry 130 Amps in open air. I will appreciate any help you can provide. Some electrical people I talk to say DC current is like water, so that you can use the entire cross-section of the triangle as it is like spilling into a tank, but what about the other end? A. Hello again, Petr. ; J Sorry that it's hard to be of much more help from such a distance. My question are: 3bi50PK k`eiWj. trailer But the fact is, 1000 Amps/sq. Save my name, email, and website in this browser for the next time I comment. I've already offered my opinion on cables and the sizing criteria I use twice on this page; maybe someone will offer a second opinion. Thanks. plating on plastics - New Delhi, India. Ampacity rating to be used when the long axis of the bars is in the horizontal plane, or when the spacing between bars is less than the thickness of the bars, or when the bars are run in a vertical direction. I think that page should be fine for AC current calculations. But in my own experience, plating shops rarely use plated ends or buss bar clamps: they just drill holes, and wire brush No-Ox-Id compound onto the joint area before bolting together. 0000012813 00000 n CDA would encourage the reader to use the more conservative of the two figures, if there is a discrepancy. Q. I have seen plating shops clear coat or lacquer their bus bar runs (except for the connections of course) and it does seem to hold up well and to look better than streaky green stained copper. L = E / (dI/dt). Our maintenance people make the fixtures, but sometimes they are not sized properly so they overheat and parts end up at the bottom of the tank. Khor, for an electroplating bussing installation I would consider the ampacity of a 12 mm x 100 mm busbar (slightly under 1/2" x slightly under 4") to be about 1860 Amps. We use rectifiers that generally operate 7-9 V and about 1500-2000 A.
This would be for a DC combiner with a positive and negative bus to combine lithium battery banks and which would be the common point to power a whole lot of 48V inverters as a large energy storage system/UPS. Fits your number perfectly. Although it's true that the insulation may make them get somewhat warmer than an open bus bar, I've never personally seen a problem if the old thumbrule of one square inch per 1000 amps of rectifier capacity is used. and as stated above it's in line with 1000 Amp/sq.in. 0000002904 00000 n 0000011365 00000 n 0000002933 00000 n Did you wire brush the joints and apply conductive joint compound? So you will see that empirical numbers are used instead. The copper bus bar is ETP-110 100% IACS (International Annealed Copper Standard) conductivity (0.15328 ohm-gram/square meter) per ASTM B187. My amperage requirement is only 1500A, but I've overspec'd for heat, losses etc in the system. Q. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. Q. Hi Ted. I have had a hard time finding information regarding this. 0000070357 00000 n I have a question for you: what's the whole voltage drop, cross section and short circuit current computing procedure of a DC busbar? For DC bussing for a rectifier, however, I think the standard number used for decades, 1000 amps/square inch for open air bussing, is an easier and safer approach. I am not an electrical person, a mechanical person and it would seem to me to be a fundamental electrical problem, yet I cannot find any information anywhere. 0000001572 00000 n Are you sure the copper is all hard drawn electrolytically pure?
Best Regards Q. Q. I am looking into the ratings for the Bus bar that is used on my anodizing tanks.
Consult'g, Train'g& Software, About/Contact-Privacy Policy-1995-2022 finishing.com, Pine Beach, New Jersey, USA, -- this entry appended to this thread by editor in lieu of spawning a duplicative thread, Plating shop owner - Vsetin, Czech Republic, product designer - hyderabad, A.P., India, Transformers - Mumbai, Maharashtra, India. Thank you, A. Hi Khaled. After calculating voltage drop (V 10.2, please correct me if I'm wrong) the loss in voltage first will result in not getting required voltage at the bus end and heat dissipation will be high (about 20.4 KVA again correct me if I'm wrong) even if I adjusted the source voltage to compensate for the voltage drop the heat is high. Good afternoon. Good luck. And would it make any difference if use cables instead of copper bars. Good Morning Affiliate Link 0000012868 00000 n I have a follow up please, what about fixtures for hanging the parts in the tank? Ceiling Fan Power Consumption Calculation, Power Saving Tips, What is Busbar Current Carrying Capacity Calculation 5 Types of Busbar, AP Electricity Bill Calculator & Rate Per unit Cost 2022, Karnataka Bescom electricity bill calculator & Latest Tariff 2022, DHBVN Electricity Calculator & Per Unit Rate DHBVN, IDMT Tripping Time Calculator, Formula, Calculation, Battery Life Calculator, Formula, Example, Formula, Torque conversion Calculation, Formula, Example, T-Match Impedance Matching Calculation, Formula, Example, Strip line Trace Width Calculation, Formula, Example, Circular Waveguide Calculation, Formula, Example, VSWR Return Loss Calculation, Formula, Example, Trace resistance Calculation, Formula, Example, Tank circuit resonance Calculation, Formula, Example, T-Pad Attenuator Calculation, Formula, Example, Skin Depth Calculator, Calculation With Example, ITI Electrician Whatsapp Group Links Join, 1500+ Active Electrical Engineering WhatsApp Group Links Join, Top 10 Electrical Website for Electrical Engineering Students, Copper bar carries 4500Amps (1.2 x 150 x 25) current, Aluminium Carries 3000 Amps (0.8 x 150 x 25) Current, GI Bus Bar Carries 2250 Amps (0.6*150*25) Current. Q. For example, For 1500 Amps Which size Copper Bars I have to use Terminal box i.e. Is this a manually operated installation? 0000001240 00000 n 0000005512 00000 n I have been going back and forwards with this for weeks. 1. And V = I x R, so I get: 0000083756 00000 n 0000001485 00000 n The following tables have been provided by the Alliance for Telecommunications Industry Solutions (ATIS), T1 Committee, and represent ampacities for busbar sizes and arrangements typically found in the telecommunications industry. If you didn't understand something and want clarification, that's fine -- people will try explaining it in different words but few readers will even read let alone try to answer a question that was already answered and is then simply repeated :-). If these charts indicated higher ampacity than the simple old-fashioned method, I'd want to go along with them. The rectifier terminal often implies what size bus bar the rectifier manufacturer feels is appropriate. I dont think the busbars are sufficient to carry that current but these are the standard busbars they send to everyone?? Please advise.
Are these results based on peak current capability or sustained current capability? Using my current bussing, what are my limits on DC Amperage, and what is the temperature rise above ambient that I should factor in? .Xk6s(s$~h$H% Q. DC resistance of copper bus bar. There response was: I think the correct answer will be slightly more than 1/10 of a square inch for a peak load for only one second, but I can't say for sure, and feel that the codes probably want you to size things based on maximum-ever loads for safety, not usual loads. HTPn0Stt4$>v@$@FGq++N:d3 2m8w4zh!/iD0z'!/H-XYOpB]j QJ{Awu47]V|Yrx1-8oY-` j` If you wish to purchase a copy of the complete Standard, please visit the ATIS Document Center. e.g. Z ig[c7y6tl6 Q"*&}w ]BSA!(jB%[3HRe0%>C\~KyIwz[ q54fZ=6a7fv.ES:ElG5v_1*bTc1N1VI5McnlRI36VN46jehA Nn~Od[JnMqQ-cp_XdcJr,Ri}v9l/)fohp:=?H'L}NxT Fp0ZF0T=T&Cnq3~*Bg8Q):NTwO e?=P'Iti`=);F&!x}6~! The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful. Will connecting both ends of the cathode bar decrease the resistance through the cathode bar to the 40 plating racks evenly spaced on the bar? My existing plating tanks have undersized cathode bars (3"x .75", 4000A rectifier) which cannot be upsized. R6td&jPj kT4y. Hopefully someone who knows will help us. No abstract questions. Regards. This is specifically regarding hard chrome plating but can be applied to other types of plating as well. The ampacities that follow are from Table 5 of Standard T1.311, and are reproduced here solely for the convenience of the viewer. Thanks, A. 0000017420 00000 n I am building a LiFePO4 battery with 280aH cell (8s configuration 24V) and they sent me tinned clad busbar (copper inside) of 2mm thick and 20mm wide by 90 mm length ( I know length does not matter). 0000070279 00000 n Architecural Manufacturers & Distributors, Architectural Installation Contractors Database, UNS Standard Designation for Wrought and Cast Copper, ASTM Standard Designation for Wrought and Cast Copper and Copper Alloys, European Numbering System for Non-Ferrous Metals, The U.S. Copper Industry: Critical to Keeping the U.S. Q. Sorry, but we'd just run in circles and never get anywhere if, after 30 postings on a subject, instead of asking for specific clarifications people just say "start over and tell me everything" :-). 0000000998 00000 n xref cVVO.eU&D$?/m^N^]7m^zc :eXwd#i KD-NPhds"`%\GlU1^Z%lF{ Cl,al9IR2 3rRpp vwgW:_o@y e^[b[E5r'b?k1?