Linear bench power supply heatsink getting extremely hot.

[Ross1204]

Hello, 

I have recently purchased this linear power supply to power my Heq5 pro mount and laptop. 

http://www.kcb.co.uk/shop2/contents/en-uk/p1722_QJE_QJ1863__10A_Power_Supply.html

I cut the cigarette end of a 4 way 12v splitter and fitted banana plugs to connect to the supply. I then plug one cable to the mount and the other to a 12v laptop charger.

Everything seems to be powered OK no power light flicker when slewing or tracking (tested indoors) but I did notice the heatsink on the power supply got really hot fairly quickly.

I would imagine this is somewhat natural given the job it's doing but is it safe?

I also noticed the cigarette socket end  that was also plugged in to the splitter for the laptop was really hot but the mount one was not. 

Any advice would be much appreciated 

Thanks

Ross

[LightBucket]

BeCareful with 12v cigar socket splitters, as some of them are not rated very high, maybe 3 or 5 amp tops, i had an issue, i have a 15 amp bench supply and each time i slewed the mount the red light on the mount flickered and my laptop went off....took me ages to figure it out, and it was the wire from the 12v cigar socket splitter that couldn’t handle the current draw...

As for the heatsink thay will get hot, thats its job..

[symmetal]

It's normal for linear power supplies to run hot. They are generally not very efficient. The mains transformer secondary winding has to deliver the 10A at a DC voltage after rectifying and smoothing, around 3V or more than your actual output voltage. The extra voltage being used in driving the output transistors. The smoothing capacitors have to be driven at an even higher voltage to stop the DC dropping below this 3V threshold on full power. Due to power losses in the transformer the transformer voltage output drops the more current you take. When you are drawing only 3A or so the transformer will supply more voltage and your smoothing capacitor voltage will be significantly higher than the 3V threshold too. All this extra power must be dissipated as heat in your output transistors. If you can keep your fingers on the heat sinks for a few seconds without going oww, you're OK.

Here's an article on power supply basics which may help.

The cigarette plug going to your laptop getting hot points to a poor connection at your splitter. Try pushing and rotating the plug in the splitter or check the tip of the plug or the connection it touches in the splitter for corrosion. If the plug has a fuse in it the fuse may not be seated firmly leading to a poor connection. Poor connections means increased resistance which means more heat.

Alan

[ChrisCM]

Ditch the cigar lighter sockets/plugs, they’re really not up to the job. I use Anderson connectors for all my 12v dc connection, on my Astro Gear, Ham Radio and my Land Rover. They are very reliable and even the smallest is rated at 15A @ 12v dc. If only the vehicle manufacturers would stop fitting “cigar lighter” sockets to cars then they would soon die out.

https://www.12voltplanet.co.uk/anderson-powerpole-connectors.html

 

Chris

 

 

[kirkster501]

I've always found it astonishing that the de facto standard 12v connector for such incredibly expensive gear is the cigar lighter....  Might br good for lighting a fag in a car but for powering mounts, cameras worth thousands? Geez....

[Ross1204]

Thanks for all your replies.

I have been searching online to see if there are any more specs for the splitter I have brought to see if this could be the most likely issue.

The first picture is from a auto parts store in america which states the maximum amperage of 2.0. Now I will say I don't really understand what that means exactly but when my power supply is a consistent 10amps and I understand my mount will draw no more than 2amp and finally the laptop will likely be between 2/3amps am I overloading the splitter? Everything seemed to work OK in a indoor test in that the power to the laptop was stable and the mount would slew and track without any drops for at least 30-45mins or so.

The second picture is off the site I used to buy it which lead me to think with 10amp fuse protection is should be good. I am unsure which site to believe currently.

I also did look into the power poles and hooking it up to a powerpoles rig runner but would that solve the heat issues? I am still yet to fully test outside but if it gets that hot after 30-45mins makes me a little cautious.

Thanks

Ross

[symmetal]

Hi Ross. The 2.0A rating on the first advert is I believe stated just to avoid overloading the input to the splitter assuming each output is delivering 2 amps. In reality the total current drawn from the splitter shouldn't exceed 10A so one socket could deliver all 10A if the other 3 weren't being used. However they may have used thin wire in connecting up the splitter internally which means the wire could get hot if it delivered more than a few amps per connector. Also the switches used on each output may only be 2A rated leading to the 1st advert statement. The connectors themselves may be rated at 10A but the internal wiring and switches may not be. You would have to take it apart to check. The switches do look rather small for a 10A DC rating.

With your overheating laptop connection is it the splitter that is getting hot or the cigarette plug going to the laptop which is hot?

Using the rigrunner instead, or similar connection methods, would certainly avoid the heating problem like you have in your cigarette connectors.

Alan

[LightBucket]

1 hour ago, Ross1204 said:

Thanks for all your replies.

I have been searching online to see if there are any more specs for the splitter I have brought to see if this could be the most likely issue.

The first picture is from a auto parts store in america which states the maximum amperage of 2.0. Now I will say I don't really understand what that means exactly but when my power supply is a consistent 10amps and I understand my mount will draw no more than 2amp and finally the laptop will likely be between 2/3amps am I overloading the splitter? Everything seemed to work OK in a indoor test in that the power to the laptop was stable and the mount would slew and track without any drops for at least 30-45mins or so.

The second picture is off the site I used to buy it which lead me to think with 10amp fuse protection is should be good. I am unsure which site to believe currently.

I also did look into the power poles and hooking it up to a powerpoles rig runner but would that solve the heat issues? I am still yet to fully test outside but if it gets that hot after 30-45mins makes me a little cautious.

Thanks

Ross

HEQ5 Pro loaded will draw more than 2 amps i would have thought...??

[Ross1204]

1 hour ago, symmetal said:

Hi Ross. The 2.0A rating on the first advert is I believe stated just to avoid overloading the input to the splitter assuming each output is delivering 2 amps. In reality the total current drawn from the splitter shouldn't exceed 10A so one socket could deliver all 10A if the other 3 weren't being used. However they may have used thin wire in connecting up the splitter internally which means the wire could get hot if it delivered more than a few amps per connector. Also the switches used on each output may only be 2A rated leading to the 1st advert statement. The connectors themselves may be rated at 10A but the internal wiring and switches may not be. You would have to take it apart to check. The switches do look rather small for a 10A DC rating.

With your overheating laptop connection is it the splitter that is getting hot or the cigarette plug going to the laptop which is hot?

Using the rigrunner instead, or similar connection methods, would certainly avoid the heating problem like you have in your cigarette connectors.

Alan

Hi Alan,

Seems perfectly logical for them to state the maximum of 2amps as to not overload the splitter, solves that question I would say.

With regards to the laptop connection I don't really recall the charging plug itself being overly hot just the cigarette plug that was in the four way splitter. I also noticed that when I had both the laptop and mount plugged in to the splitter all the switches would light up and stay on but when removing either one they would work normally again being able to toggle on and off.

Just a little disconcerting as spent a decent amount in buying all the power supply and cables to only find it isn't ideal still potentially.

Makes me wonder if you can buy more durable 12v cigarette splitters as not sure where I can buy a good sufficient powerpole distribution box as all seemed pretty expensive from the brief searching I did before. 

Thanks

Ross

[Ross1204]

39 minutes ago, LightBucket said:

HEQ5 Pro loaded will draw more than 2 amps i would have thought...??

Gonna have to play the ignorance card as basing that purely on other forum posts I've read and other users direct suggestions to a couple of questions I have asked in relation to the power requirements.

Thanks

Ross

[LightBucket]

13 minutes ago, Ross1204 said:

Gonna have to play the ignorance card as basing that purely on other forum posts I've read and other users direct suggestions to a couple of questions I have asked in relation to the power requirements.

Thanks

Ross

Yes i dont know for sure as i have the EQ6 and that will draw up to 5 amps loaded...

[symmetal]

Ross, the fact that all 4 power lights on the splitter come on when you plug 2 items in does suggest that it is wired rather oddly  and not built to do the job intended. Looking through Amazon it appears similar splitters have a total rating of 120W (10A) with absolute max 40W per socket (3A per socket on 12V). They probably have an internal PC board instead of actual wiring which is where the lower current rating is stated per socket. There is this one that is rated at 200W total which is a possible 6A from each socket simultaneously so I assume has heavier gauge wiring or PC tracks. The built in voltmeter and four 5V outputs are a bonus but how reliable the connections are with repeated insertions is the question. Ahh! Looking again it's listed as 12/24V at 200W. The 200W would probably be for 24V systems so you're possibly back to the 3A max current per socket again. It is stated as 'Ultra High Capacity' and heavy duty wiring so does imply it's more than the standard ones. Something like this would probably still be better than your current one and isn't too expensive. Until you have sorted out a more robust system of distribution like the rigrunner or similar, something like this would be OK I think. Others may have better stop-gap solutions. 

 

[symmetal]

A better alternative if you want to stay with cigarette connectors for the moment, is to get Marine Grade Sockets and fit them into a small plastic box and wire them up as you wish. You can get 2 mounted on a panel to make fixing easier and other combinations with switches, usb outlets and voltmeters. A nice little project if you like making things and not too expensive.  Marine grade sockets will give a better firmer connection than the standard splitters.

Alan

[LightBucket]

7 hours ago, symmetal said:

A better alternative if you want to stay with cigarette connectors for the moment, is to get Marine Grade Sockets and fit them into a small plastic box and wire them up as you wish. You can get 2 mounted on a panel to make fixing easier and other combinations with switches, usb outlets and voltmeters. A nice little project if you like making things and not too expensive.  Marine grade sockets will give a better firmer connection than the standard splitters.

Alan

Yes i have used those, and with the marine sockets you can get matching marine plugs, which when fitted lock in place and also have a waterproof seal...much much better than any other version..

[Ross1204]

Thank you both for the replies and advice, such a great help.

So with all things considered I decided to try the 3 way splitter from amazon listed above (Thanks Alan) and see how that goes. Just hoping that with the description stating a more robust internal arrangement it will hopefully tide me over for now and be more sufficient than the one I purchased before. The power supply will be located in the conservatory anyhow which will be much cooler than the room I set it up before so maybe that will help but that time it was only running for say 45mins and everything will be going for way longer than that if the clouds don't pop out for a natter.

I have also looked in to the Powerpoles setup more and will definitely take that avenue when I decide to get a battery and make it all portable unless this fails obviously and then there will be no time to weight. I would like to of gone that route now as likely will anyway but the cost of everything so far and Christmas a couple of weeks away the old brain stepped in and the wallet slightly closed for now........

Thanks

Ross

[symmetal]

Hope the new splitter works better than your current one Ross and lasts until your wallet gets fatter. 

When you tested your setup and the power supply got hot, was the sun shining on it at the time. I found my Nevada got really hot to touch even when it was turned off and had the afternoon sun on it through the open shed door. This would seriously inhibit its ability to dissipate the normal heat produced when operating.

Alan

[Ross1204]

20 hours ago, symmetal said:

Hope the new splitter works better than your current one Ross and lasts until your wallet gets fatter. 

When you tested your setup and the power supply got hot, was the sun shining on it at the time. I found my Nevada got really hot to touch even when it was turned off and had the afternoon sun on it through the open shed door. This would seriously inhibit its ability to dissipate the normal heat produced when operating.

Alan

Hi, Alan.

When testing the setup the power supply was situated on a small side table off the floor in the living room so zero affect from the elements. I also don't think the room temperature would of had that much of a influence to make it that hot. The splitter arrived today but can't test anything this evening so will be in the coming days.

Ross

[Grierson]

Ross, I wonder if you have run the power supply without any load. Does it still get very hot? 

Do you have a meter to measure the current to your rig. If not a simple test meter is a worthwhile investment to sort this issue and will come in very handy for future problems. - John

[K4PDM]

Does the laptop actually take 12V? Most of the ones I've seen need a 19V power supply.

If it was supposed to be 19V, it might draw a lot of current if you tried to operate it at 12V.