Page 2 of 5 FirstFirst 12345 LastLast
Results 21 to 40 of 91

Thread: Adjustable bench power supply - buy or build yourself?

  1. #21
    Member
    Johnno's Avatar
    Join Date
    Jan 2008
    Location
    The Dark Side of the Moon
    Posts
    379
    Thanks
    323
    Thanked 217 Times in 121 Posts
    Rep Power
    252
    Reputation
    4351

    Default

    Ok, That's it.. lol Ya pissed me off with that 20 amp monster.. lol I'm bringing out the heavy Artillery.. lol

    My VK will kick your bertha arse... lol


  2. The Following 2 Users Say Thank You to Johnno For This Useful Post:

    hinekadon (07-05-20),lsemmens (06-05-20)



  • #22
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Quote Originally Posted by Johnno View Post
    Ok, That's it.. lol Ya pissed me off with that 20 amp monster.. lol I'm bringing out the heavy Artillery.. lol

    My VK will kick your bertha arse... lol

    Ummm13.8V fixed, with 15A, 25A int? And mines variable output voltage, with current limiting.. 20A constant.. but hey, it ain't (really) a pissing contest LOL

  • The Following 2 Users Say Thank You to bob_m_54 For This Useful Post:

    Johnno (06-05-20),lsemmens (06-05-20)

  • #23
    Premium Member
    wotnot's Avatar
    Join Date
    Nov 2019
    Posts
    790
    Thanks
    273
    Thanked 545 Times in 335 Posts
    Rep Power
    253
    Reputation
    10910

    Default

    it ain't (really) a pissing contest LOL
    Hahaha, yes it is =)

  • The Following User Says Thank You to wotnot For This Useful Post:

    lsemmens (06-05-20)

  • #24
    Member
    Johnno's Avatar
    Join Date
    Jan 2008
    Location
    The Dark Side of the Moon
    Posts
    379
    Thanks
    323
    Thanked 217 Times in 121 Posts
    Rep Power
    252
    Reputation
    4351

    Default

    LOL... My VK Dick Smith Electronics psu has been hacked.. lol PSU porn inside my VK... LOL I like yours though.. lol So, Let's call it a draw..
    Last edited by Johnno; 06-05-20 at 08:11 PM.

  • The Following User Says Thank You to Johnno For This Useful Post:

    lsemmens (06-05-20)

  • #25
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Quote Originally Posted by wotnot View Post
    hahaha, yes it is =)
    lol

  • The Following User Says Thank You to bob_m_54 For This Useful Post:

    lsemmens (06-05-20)

  • #26
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Quote Originally Posted by Johnno View Post
    LOL... My VK Dick Smith Electronics psu has been hacked.. lol PSU porn inside my VK... LOL I like yours though.. lol So, Let's call it a draw..
    Yep OK LOL. Actually, at the time that pic was taken, I was using it for electrolytic de-rusting. But I have also used it to drive a (suitcase) 48V external wire drive, for a mig welder.

  • The Following 2 Users Say Thank You to bob_m_54 For This Useful Post:

    Johnno (06-05-20),lsemmens (06-05-20)

  • #27
    Premium Member
    wotnot's Avatar
    Join Date
    Nov 2019
    Posts
    790
    Thanks
    273
    Thanked 545 Times in 335 Posts
    Rep Power
    253
    Reputation
    10910

    Default

    Just wandered down the shed to get this pic of the old Arlec 30Amp multicharger (6-12-18-24 volt), with auto cutout timer (gosh!!) Current/voltage regulation is by a multi-tapped transformer ( think it was 8 taps) and complex multi-pole switch. The bypass switch turns it into a FLA battery cooker/cell dehydration unit =)



  • The Following User Says Thank You to wotnot For This Useful Post:

    Johnno (06-05-20)

  • #28
    Senior Member

    Join Date
    May 2018
    Posts
    1,788
    Thanks
    392
    Thanked 1,557 Times in 731 Posts
    Rep Power
    699
    Reputation
    30714

    Default

    I had a power supply given to me that was 24V @ 140A.
    Was called a forklift battery charger. :0)

    It was a great power supply and worked well as one but I didn't have much need for 24V and didn't have enough knowledge at the time to do other things with it so I sold it. At least I got real good money for the thing.
    Took 3 of us to load it on the guys ute and was a good job we made it first time because there wouldn't have been a 2nd attempt.


    I found a Repco Branded battery charger in a scrap bin one time. Took it home plugged it in and it worked fine. Does a proper 20A+. It is one of my favourite tools.
    The neighbour had one the same I spotted last week. Old as the hills like mine but his had Arlec on it but was the exact same case design. Obviously Repco got them to make it and put their branding on it.

    Simple and rugged thing, big tranny, uses one side of a bridge rectifier for the half wave for low power and does 6V. I have added some caps and a a regulating board so I can use it as an auto battery charger or a power supply. Panel meter has Dies So I think I'll just put in a DC power meter and a PWM Controller so I can regulate the charge or power supply output.

    I doubt they make them like that any more and if they did, I couldn't afford it! :0)

  • The Following 2 Users Say Thank You to george65 For This Useful Post:

    Johnno (06-05-20),wotnot (07-05-20)

  • #29
    LSemmens
    lsemmens's Avatar
    Join Date
    Dec 2011
    Location
    Rural South OZ
    Posts
    8,992
    Thanks
    8,943
    Thanked 5,658 Times in 2,712 Posts
    Rep Power
    2491
    Reputation
    104420

    Default

    Will you blokes stop pissing? I'm feeling left out!
    I'm out of my mind, but feel free to leave a message...

  • The Following 2 Users Say Thank You to lsemmens For This Useful Post:

    Johnno (06-05-20),wotnot (07-05-20)

  • #30
    Member
    Johnno's Avatar
    Join Date
    Jan 2008
    Location
    The Dark Side of the Moon
    Posts
    379
    Thanks
    323
    Thanked 217 Times in 121 Posts
    Rep Power
    252
    Reputation
    4351

    Default

    Very Nice wotnot, also George's unit sounds tuff.. But, I have to confess - I really like Bob's.. lol

    Wanna trade Bob ?? I have 9 kids all toilet trained - Pick One. LOL

  • The Following User Says Thank You to Johnno For This Useful Post:

    wotnot (07-05-20)

  • #31
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Haha, well technically, I've worked on up to 48V >600A power supplies (welding power supplies). We used to load test them by connecting them to a series of alternating stainless steel plates, dunked into a 44gal drum of salt water. The more of the plates in the saltwater, the more current you draw Then run them at @ 500A for about 20 mins, long enough to make the 95mmsq leads get uncomfortably hot.

    Funny thing one day, one of the "qualified" electricians was standing there in awe of how much current was drawn and the salt water boiling in the drum, and didn't believe when I said about 500A. He put a tong meter on the cable and it was actually running around 550A. I said to him, stick your finger on the terminal.. he looked at me like I was crazy, told me to bugger off etc.. I said it's OK, it won't hurt you. Then stuck my finger on the pos output terminal. He near shit hisself... but I was wrong, the terminal wasn't quite tight enough and the heat generated did burn a tad. But he couldn't get his head around the fact that there wasn't enough voltage to be much more than a mild tingle on dry fingers, even across both terminals.

  • #32
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Quote Originally Posted by Johnno View Post
    Very Nice wotnot, also George's unit sounds tuff.. But, I have to confess - I really like Bob's.. lol

    Wanna trade Bob ?? I have 9 kids all toilet trained - Pick One. LOL
    9??? you need to by a TV mate.

  • The Following 2 Users Say Thank You to bob_m_54 For This Useful Post:

    GT250 (09-05-20),lsemmens (07-05-20)

  • #33
    Senior Member
    bob_m_54's Avatar
    Join Date
    Jan 2011
    Location
    Newcastle, Australia
    Posts
    1,844
    Thanks
    859
    Thanked 920 Times in 573 Posts
    Rep Power
    489
    Reputation
    15558

    Default

    Quote Originally Posted by wotnot View Post
    Just wandered down the shed to get this pic of the old Arlec 30Amp multicharger (6-12-18-24 volt), with auto cutout timer (gosh!!) Current/voltage regulation is by a multi-tapped transformer ( think it was 8 taps) and complex multi-pole switch. The bypass switch turns it into a FLA battery cooker/cell dehydration unit =)


    I've got a newer one of those. Picked up from a garage sale for $30.00


  • The Following User Says Thank You to bob_m_54 For This Useful Post:

    Johnno (07-05-20)

  • #34
    Premium Member
    ol' boy's Avatar
    Join Date
    Jan 2008
    Posts
    17,662
    Thanks
    8,131
    Thanked 10,453 Times in 5,193 Posts
    Rep Power
    4423
    Reputation
    184132

    Default

    Quote Originally Posted by lsemmens View Post
    Will you blokes stop pissing? I'm feeling left out!
    Hold my beer...

    If u want to go on an expedition get a Land Rover, if u want to come home from an expedition get a Landcruiser!

  • The Following 3 Users Say Thank You to ol' boy For This Useful Post:

    bob_m_54 (08-05-20),Johnno (07-05-20),lsemmens (07-05-20)

  • #35
    Premium Member
    wotnot's Avatar
    Join Date
    Nov 2019
    Posts
    790
    Thanks
    273
    Thanked 545 Times in 335 Posts
    Rep Power
    253
    Reputation
    10910

    Default

    Heartening to know I'm among true voyeurs of the old state of the art...it's like mini-skirts ; to truly appreciate it, you had to be there at the time =)

    Woke up this morning, and figured I should have a close look over the es460c boards again, because I did notice a couple of pet hate components during the teardown... sure enough ;




    Rotten things they are, the chemistry in the case plastic goes sour after years (20 of them) in storage, so they're going to need replacing before power on.






    @george65 -- check yours, but I imagine it'll be the same deal. I have to buy an ssm of 10 units in a bag, so I'll have 4 spare if you're interested =)

    So I'm headed for a full disassembly service... oh goody, more fun..

  • The Following User Says Thank You to wotnot For This Useful Post:

    Johnno (07-05-20)

  • #36
    Senior Member

    Join Date
    May 2018
    Posts
    1,788
    Thanks
    392
    Thanked 1,557 Times in 731 Posts
    Rep Power
    699
    Reputation
    30714

    Default

    Quote Originally Posted by wotnot View Post

    So I'm headed for a full disassembly service... oh goody, more fun..
    Yeah, Exactly.

    I'll bet they are absolute Bitches to get to. Let me know how difficult they are. Thank you for the offer but I'm thinking might be easier just to call this one over my head and scrap the thing. Not in the head space to be pulling them apart and mucking round with them atm and can't see when I will be.

  • #37
    Premium Member
    wotnot's Avatar
    Join Date
    Nov 2019
    Posts
    790
    Thanks
    273
    Thanked 545 Times in 335 Posts
    Rep Power
    253
    Reputation
    10910

    Default

    I'll bet they are absolute Bitches to get to.
    Not actually... when I was doing the peekboo and trying not to drool on things, I could see this was designed by an Italian engineer who was thinking of Sophia Loren in a mini-skirt...like this =)




    Haha....when you see the thermistor connector is fitted with plug and long tail, you just know the things are built to be undressed. There's 4 screws on the heatsink fin side securing the mosfet carrier - this is easy to do because the 5 tall brass stand-off posts on the other side, support and hold things so components don't get crushed (in fact, you could remove these four screws with the case cover still on), then flip it over and there's another 4 screws you can get at via the access holes in the PCB, to release the mains bridge, the two double-diode packs, and a weight support stand-off adjacent the big heavy output transformer (attention to detail in the construction of these is impressive)....then unplug the thermistor connector, remove the 5 tall stand-off posts, and then the heatsink can be separated from the entire PCB assembly, no desoldering required. Then you can repair/rework the PCB assembly as required, renew thermal transfer compound, drop the PCB assembly back ontop of the heatsink, reassembly is the reverse of disassembly...and because it's all so easy and well thought out from a service perspective, you say "Grazie" aloud, to thank those responsible =)

    Like I say, this gear is built to a different level of civilized engineering that you don't see much in the wild anymore...certainly not at domestic appliance level. For instance, the bridge controller IC they've used is entry level @ industrial spec. You can only go 3 grades higher - 'enhanced' (accuracy/reliability) for instrumentation/medical use, Mil spec, or Space spec...and TI still have these in active production.

    If I'm going to need go into bat with this pissing match, with this beautiful rectifier brick, I'll have to speak to component level, and the hand assembly, care & attention to mods...it'll do another vid when I get to it, should be fun =)


    Quote Originally Posted by lsemmens View Post
    Agreed, that is an impressive bit of kit. What is it's "Official" rating? i.e. input/output power and voltages. I have no need of such a thing, so I am just curious?
    You know what that reminds me of? The old joke about the guy who rocks up to the Rolls Royce dealership, and asks the sales person "what's the official power output of the engines in these things?", to which the sales person replies "More than adequate"

    I can tell you now, I'm going to expect to find all the diode/switching silicon to be over-rated to the billy-oh... and the only real measure will be practical testing, but theoretical would be 460/48=9.58A but they only cite 7.2A available on the 48VDC output, which is 345watts...the second output transformer, which I'm guessing may be a 12VDC supply rail, looks like it's capable of a few amps, so add in some inefficiencies (we started with 240VAC @ 3A) and the maths seem to work...we'll find out when I can use the dps5015 to dump into a load beyond the unit's actual spec... I'll take notes =)

  • The Following User Says Thank You to wotnot For This Useful Post:

    lsemmens (07-05-20)

  • #38
    Member
    Johnno's Avatar
    Join Date
    Jan 2008
    Location
    The Dark Side of the Moon
    Posts
    379
    Thanks
    323
    Thanked 217 Times in 121 Posts
    Rep Power
    252
    Reputation
    4351

    Default

    Quote Originally Posted by bob_m_54 View Post
    9??? you need to by a TV mate.
    Hehe.. That was me trying to be funny.. lol /fail

    In reality - 2 grownUp Kids that have left home but still ring me and ask for money.. Lucky me.


    @ wotnot, Those 4.7nf Caps won't take that long to replace.. Seems the casing has deteriorated - could be some sort of wax or is it plastic ?

    Oh, The hardware is so sexy...

    I still have a 240v Variac to bring out of my workbench weapon arsenal if I feel threatened in anyway.. lol
    Last edited by Johnno; 07-05-20 at 02:17 PM.

  • #39
    Senior Member

    Join Date
    May 2018
    Posts
    1,788
    Thanks
    392
    Thanked 1,557 Times in 731 Posts
    Rep Power
    699
    Reputation
    30714

    Default

    Quote Originally Posted by Johnno View Post

    In reality - 2 grownUp Kids that have left home but still ring me and ask for money.. Lucky me.
    I have a father that is continually trying to give me money.... Or a car or.... something.
    You buy something he needs for him for 100 and he's trying to shove 1000 at you.

    He now rings me for help and advise. I have younger mates whom are grandparents but finally my father treats me like a Son.
    It's nice and I hope it/ he lasts a lot longer.

    I wondered about the 9 Kids, only because I know 2 couples that have 7. All their own, not baggage from previous marriages. One guy has a 9 bedroom house. The living areas are proportionate as is the Kitchen and multiple bathrooms. Many of my friends have 3 Kids. No way I was going to let the children outnumber the parents!

  • #40
    Premium Member
    wotnot's Avatar
    Join Date
    Nov 2019
    Posts
    790
    Thanks
    273
    Thanked 545 Times in 335 Posts
    Rep Power
    253
    Reputation
    10910

    Default

    Quote Originally Posted by Johnno View Post


    @ wotnot, Those 4.7nf Caps won't take that long to replace.. Seems the casing has deteriorated - could be some sort of wax or is it plastic ?

    They're easy enough... yes, it's the casing that deteriorates and cracks, which lets moisture into the paper dielectric, which swells, causes the case to crack further, which lets in more moisture, which makes the paper swell even more, and even more moisture gets in, until you're left with this damp wad of paper between active & neutral, encapsulated by some substance many guess as being synthetic shellac ( ), and this all happens while they're sitting on the shelves, in stock, doing nothing....the moment you apply mains, BLAMMO!...

    It's a common mode failure with these old RIFA caps...on that first unit I looked at, I was hunching another RIFA I spotted should likely be replaced...I set about opening/checking the other 2 bricks, and sure enough;



    Split case, typical of old Rifa caps like this, so 3 bricks in for service before entry into duty...

  • Page 2 of 5 FirstFirst 12345 LastLast

    Bookmarks

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •