my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Choke value for Strong 61000 power supply

Author Topic: Choke value for Strong 61000 power supply Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 05-04-2012 11:15 PM                     I'm in need of getting a rewind done on the choke for a Strong 61000 power supply and need the value so I can get the work done. Would any one know what the Inductance and resistance values are for this choke? Cheers Ian  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 05-07-2012 12:02 AM                     Why does it need to be rewound? Burned up, water or other physical damage, or noisy? Any competent transformer shop can, if all the original windings are there (even if badly damaged), rewind it properly. If the laminated core is ok you can even rewind it yourself following a few simple rules: 1: Use same gauge and insulation type of wire; 2: Wind the exact same number of turns in the same direction and laydown pattern of the original; 3: Dip the finished assembly in transformer varnish and bake it to dry it out. Only Strong would know those values and good luck getting them to tell you.  |  IP: Logged Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 05-07-2012 12:14 AM                     Thanks for the suggestions, Tony. It's got an open winding and I was hoping to have a bash at winding a replacement coil. I did find an onsite calculator for winding chokes which is here for posterity. D.C choke winding formulas. I haven't yet tried Strong for the choke specs, but based on your advice I may well forget that line of action. Many Thanks for the suggestions... I'm off to get this thing sorted.  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 05-07-2012 12:24 AM                     You're welcome and best of luck to you. Making sure I am clear since you didn't give specifics (and I am very tired as I was working in Corona getting set up for my annual Renaissance Fest) are we talking a heavy output choke on a magnetic rectifier or a choke on a switching rectifier's control board? Reason I am asking is that if it is an output choke wound with heavy-guage wire the tolerances are not very critical and a do-it-yourself attempt has a high chance of success. One of the smaller chokes on a switcher's control circuitry however has to be done just right or it may fail to work properly or even cause damage to the control electronics. If you can post pics of the choke in question and it's location in the rectifier that would be helpful.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 05-07-2012 08:27 AM                     Unwind the old choke measure the length of wire and cut a piece of the same guage and length and rewind it onto the core and it will be almost the same Remember at best large currents chokes are often 10% tolerance  |  IP: Logged Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 05-21-2012 06:58 PM                     Update. I gave up trying to get any values out of Strong and so tried Gordon's method and all is now well...not much fun but successful nevertheless. Thanks Guys!  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-21-2012 07:24 PM                        Is this the 2Kw single phase, high reactance unit? If so, they added an (unnecessary) choke on some models. I have removed it with no ill effects. It was noisy due to the magnetic effect of its mounting. Remember, I live in 60 Hz land. louis  |  IP: Logged Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 05-21-2012 11:24 PM                     That's the unit, Louis. They aren't much quieter here in Slow Power land either. Knowing what you have said, I'll try the same thing and see how it runs. Many Thanks  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-22-2012 12:21 AM                       Strong did an all around bad job on the construction of the chokes but the idea was to improve the inrush current and the ripple. These are both critical to long bulb life with no flicker. I would be careful about removing it without some thought about these issues.  |  IP: Logged Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 05-22-2012 02:48 AM                     I was thinking about beefing up the filtering caps. Granted, that would increase the inrush but the output smoothing would be a bit better.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-22-2012 06:52 AM                        Whenever I have something fail in a 50 Hz country, I blame it on "slow electricity." Louis  |  IP: Logged

All times are Central (GMT -6:00)

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.