Busbar Coating Guideline with Epoxy Coating Powder

In this arti­cle we will explain how to use epoxy coat­ing pow­der to prop­er­ly coat bus­bars, both alu­minum or copper

Low Voltage Busbars and Medium Voltage Busbars

Whether you are using epoxy coat­ing pow­der to coat low volt­age bus­bars or medi­um volt­age bus­bars, or whether you are using alu­minum or cop­per bus­bars, this guide­line will help you. This is what a sam­ple process (or recipe) will look like. Once the process engi­neer com­pletes the process devel­op­ment he will have some­thing like what is shown below. Gen­er­al­ly they will select the options on the HMI and the PLC will set the cor­re­spond­ing val­ues for the line to run – for sophis­ti­cat­ed systems.

Bus­bar Epoxy Coat­ing Guideline
Part geom­e­try
(Width x Thick)
Mate­r­i­al Volt­age rating Required Coat­ing thick­ness (mils) Pre­heat temp (°F) Pre­heat Time (mins) #
Cure tem­per­a­ture (°F) Cure Time (mins)
Top of Page
Epoxy Coat­ing Guide­line for Busbars
Low Volt­age Bus­bars (up to 600V)
2 to 8″ * 1/4″
50–200mm x 6.35mm
Cop­per 600 V 20 to 30 340 20 to 24 1 380 to 400 20 to 24
Alu­minum 600 V 20 to 30 360 20 to 24 1 380 to 400 20 to 24
2 to 8″ * 1/8″
50–200mm x 3.18mm
Cop­per 600 V 12 to 20 320 20 to 24 1 380 to 400 20 to 24
Alu­minum 600 V 12 to 20 320 20 to 24 1 380 to 400 20 to 24
Epoxy Coat­ing Guide­line for Busbars
Medi­um Volt­age Bus­bars (up to 38,000 Volts)
1/4″ (6.35mm) Cop­per 5 kV & 15 kV 60 to 80 400 — 420 20 to 24 4 340 to 380 20 to 24
3/8″ (9.53mm) Cop­per 5 kV & 15 kV 60 to 80 390 — 410 20 to 24 3 340 to 380 20 to 24
1/2″ (12.7mm) Cop­per 5 kV & 15 kV 60 to 80 370 — 385 20 to 24 3 340 to 380 20 to 24
1/4″ (6.35mm) Cop­per 27 kV & 38 kV 100 to 125 440 — 460 20 to 24 5 340 to 380 20 to 24
3/8″ (9.53mm) Cop­per 27 kV & 38 kV 100 to 125 420 — 440 20 to 24 4 340 to 380 20 to 24
1/2″ (12.7mm) Cop­per 27 kV & 38 kV 100 to 125 390 — 410 20 to 24 4 340 to 380 20 to 24

Please vis­it us at www.caplinq.com to learn more about our whole range of epoxy coat­ing pow­ders includ­ing our halo­gen-free Lin­q­sol BCP-1504 which is devel­oped specif­i­cal­ly for bus­bar epoxy coat­ing appli­ca­tions includ­ing both low volt­age (<600V) bus­bars as well as medi­um volt­age (up to 38kV) bus­bar appli­ca­tions.

If you have any oth­er ques­tions about how best to clean your molds, the prod­ucts you can best use to clean them, or the appli­ca­tion meth­ods of these mate­ri­als, please feel free to leave a com­ment below, or don’t hes­i­tate to con­tact us.

About Chris Perabo

Chris is an energetic and enthusiastic engineer and entrepreneur. He is always interested in taking highly technical subjects and distilling these to their essence so that even the layman can understand. He loves to get into the technical details of an issue and then understand how it can be useful for specific customers and applications. Chris is currently the Director of Business Development at CAPLINQ.

8 thoughts on “Busbar Coating Guideline with Epoxy Coating Powder

  1. Dear Mr. Chris Perabo,
    Ref­er­enc­ing to your this blog. I was try­ing to search any rel­e­vant lit­er­a­ture relat­ed to Bus­bar Epoxy coat­ing, until I reach to your blog. You blog would sure be ben­e­fi­cial to many of us. 

    From the same blog, I am inter­est­ed to ask few ques­tion, for my under­stand­ing. In the tab­u­lat­ed data you present, for the Medi­um Volt­age Bus­bars (up to 38,000 Volts). I noticed, that with the increas­ing bus­bar thick­ness, the pre-treat­ment tem­per­a­ture, coat­ing thick­ness and the num­ber of dips are decreas­ing. Where­as my assump­tion is that with increas­ing bus­bar thick­ness, the pre-treat­ment tem­per­a­ture (if we keep the same time), coat­ing thick­ness and the no., of dips must increase. 

    Could you please explain for my bet­ter understanding. 


    Amin Ali Shah

  2. Hel­lo Amin,

    You are cor­rect that you want to have a thick­er coat­ing when you are using larg­er bus­bars. How­ev­er, when you use larg­er bus­bars, these retain much more heat than small­er bus­bars, which means that there is MORE pick­up of epoxy coat­ing pow­der with every dip and there­fore also a FEWER num­ber of dips are need­ed to achieve the required thickness.

    I hope this helps. If you have any more ques­tions about epoxy coat­ing pow­der for switchgear and pow­er dis­tri­b­u­tion includ­ing low volt­age bus­bars and medi­um volt­age bus­bar coat­ing, please do not hes­i­tate to con­tact us.

  3. Dear Mr. Chris Perabo,

    What type of pro­cess­ing issues would cause “pin­holes” in the epoxy coating?


  4. Hi John,

    There are sev­er­al pro­cess­ing issues that could cause pin­holes. From the engi­neer­ing side, we always look at three variables:
    a) Process
    b) Substrate
    c) Powder

    On the process side, pin­holes can be linked to the bus­bar itself being too hot or too cold. If it’s too hot, the mate­r­i­al could cure before the air has a chance to escape. If it’s too cold, the air bub­bles may form too slow­ly to escape. It can also be caused by dip­ping the bar again too quick­ly or by tak­ing too much time between dips.

    On the sub­strate side, cop­per and alu­minum have dif­fer­ent ther­mal reten­tion rates and you want to make sure you get the bars in quick­ly enough and get them out quick­ly enough that the “cool pow­der” does­n’t cool down the bar too much between dips.

    Final­ly on the pow­der side you want to make sure that the prod­uct has the right bal­ance between “Gel Time” and “Stick­ing Point”. The stick­ing point refers to the tem­per­a­ture at which the pow­der will stick to the bar, where­as the gel time refers to the amount of time the mate­r­i­al will gel when exposed to the high bus­bar temperatures.

    CAPLIN­Q’s team of sales and tech­ni­cal engi­neers are very well trained in using and trou­bleshoot­ing bus­bars. Please send an email to info@caplinq.com if we can inter­est you in a sam­ple for alu­minum or cop­per bus­bar coatings.

  5. Dear Chris..

    Hope you are doing well..

    Thanks for the detail­ing about epoxy process..
    Actu­al­ly I have few queries..
    We had thick­ness of bus bar from 2.5,4.75,6.25,9.45 like that..
    Could you please tell me..the parameters
    1. Pre heat­ing temperature-
    2. Dip­ping cycle time-
    3. No of dips-
    4. Time Inter­val required b/w dips -
    5. Post heat­ing temperature-

    Cur­rent­ly we are facing…issues like poor appear­ance of bus bars after epoxy coat­ing and then few epoxy par­ti­cles set­tled in bus bars while dip­ping inter­vals, it requires man­u­al shak­ing of bus bars .and high thick­ness reflect­ed than the margin..

    Kind­ly pls advise on the above queries and paraame­ters for each thick­ness of bus bars them how could we elim­i­nate all these cons against the process..

    Your reply was much appreciated..

  6. Hi Shafi,

    Thanks for reach­ing out. Your ques­tions are of course very good, but the answers to these ques­tions will first require more ques­tions to be asked. The rea­son for these ques­tions is because each of the answers will depend on the bus­bar epoxy coat­ing pow­ders mate­ri­als you are using as well as the mate­r­i­al the bus­bar is made of (alu­minum or copper).

    Our most pop­u­lar prod­uct LINQSOL BCP1504 is a very ver­sa­tile halo­gen-free bus­bar epoxy coat­ing pow­der.

    So let me please start with ques­tions to ask you:

    • What prod­uct are you using to coat the busbars?
    • What type of bus­bars are you coating?
    • What is your coat­ing method — are you doing flu­idized bed?
    • Assum­ing you have a flu­idized bed, how big is it (dimen­sions) and how much pow­der fits in it (kg)?

    If you have a spe­cif­ic cus­tomer inquiry, I sug­gest you also send us an email at info@caplinq.com and our Appli­ca­tions Engi­neer­ing team will be able to help you opti­mize your settings.

    Look for­ward to hear­ing from you,
    Chris Perabo

  7. Hi chris,
    Thank you for shar­ing such valu­able experience.
    I had a doubt while pow­der coat­ing bus bars, we are mask­ing the bus­bar with high temp mask­ing tape but the coat­ing thick­ness on the bus­bar is too high that it cov­ers the tape itself and when we try to peel the tape of with a sharp object it cracks up the pow­der coat­ing on the component.
    Which leads to my sec­ond ques­tion that how can we improve adhe­sion of piwder coat­ing on a tin plat­ed cop­per busbar?

  8. Excel­lent ques­tions Saksham,

    Many first-time epoxy coat­ing pow­der users see that they can mask off the areas of the bus­bar with a mask­ing tape. This is true and it is also rec­om­mend­ed. What they don’t real­ize is that you need to remove the mask­ing tape while the bus­bar and the pow­der are still warm. Once the epoxy cures and the tem­pear­ture drops, the epoxy becomes very hard and brit­tle, mak­ing it dif­fi­cult to remove the mask­ing tape as you have described.

    With even thick­er lay­ers of epoxy coat­ing pow­der, it becomes trick­i­er to peel off the tape before the epoxy cools done — but it is absolute­ly pos­si­ble. I have peeled off tape from bus­bars that have thick­ness­es of almost 5mm of pow­der, which requires many dip­ping lay­ers to achieve.

    Anoth­er trick is to use alu­minum foil to do the mask­ing and only use a bit of tape where the foil over­laps with the tape. This allows you to use much less tape and it makes it a lot eas­i­er to clean up afterwards.

    As for your sec­ond ques­tion, adhe­sion to tin. There are two ways to address this. The first is to use a good epoxy coat­ing pow­der for bus­bars that has been for­mu­lat­ed to have adhe­sion on both cop­per and tin.
    Lin­q­sol BCP-1507 Epoxy Coat­ing Powder

    The sec­ond is to use an adhe­sion pro­mot­er to adhere bet­ter to. For this I would rec­om­mend you look at:
    Methacry­late Func­tion­al Adhe­sion Promoter

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