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Current Tranformer Testing |
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 Jan 29 2010, 11:47 AM
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#1
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Junior Member  Group: Full Member Posts: 9 Joined: 25-November 09 Member No.: 7,188  |
Hi All
I don't know if this is the correct location on the forum but i'll ask anyway. I would like to know if there are any devices on the market that can simulate a variable load up to 5A, equivalent to that given out from CT's. It is for testing ammeters and over current relays before the panels leave the workshop. Are there even any testing rigs we can set up from readily available components? regards Jonny |
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Feb 7 2010, 09:27 AM
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#2
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Posting Freak Group: Moderator Posts: 2,383 Joined: 24-April 02 From: Christchurch, New Zealand Member No.: 1 |
Hello Jonny
Some years ago, I made up a special tester to apply current to CT primarys. I used a toroidal transformer, about 60VA, and wound two turns of 35mm flexible cable through the core. I connected the primary to a variac and then is was just a case of passing the 35mm cable through the test CT and joining to close the circuit. The current could be adjusted by varying the voltage into the toroidal transformer. Best regards, Mark. -------------------- Mark Empson administrator
Skype Contact = markempson | phone +64 274 363 067 LMPForum | LMP Tech Warehouse | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | LMP Software | Mark Empson Website |
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Feb 17 2010, 03:39 PM
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#3
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Junior Member Group: Full Member Posts: 9 Joined: 25-November 09 Member No.: 7,188 |
QUOTE (marke @ Feb 7 2010, 09:27 AM)  Hello Jonny Some years ago, I made up a special tester to apply current to CT primarys. I used a toroidal transformer, about 60VA, and wound two turns of 35mm flexible cable through the core. I connected the primary to a variac and then is was just a case of passing the 35mm cable through the test CT and joining to close the circuit. The current could be adjusted by varying the voltage into the toroidal transformer. Best regards, Mark. Hi Mark Thanks for the reply. It should be a big help. I'm just pricing up the components now. I've never come across a toroidal transformer before and I'm guessing that they create a current from a voltage. Is this correct? regards Jonny |
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Feb 19 2010, 12:10 PM
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#4
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Posting Freak Group: Moderator Posts: 2,383 Joined: 24-April 02 From: Christchurch, New Zealand Member No.: 1 |
Hi Jonny
A toroidal transformer is just like a standard transformer except that in construction, instead of being wound on E and I laminations, it is wound on a toroidal core. (the core is much like the toroidal core used for current transformers.) The advantage of the toroidal core for this application, is that it is easy to add a single or two turn high current winding. You could look at getting a special transformer wound with a low voltage high current secondary. Best regards, Mark. -------------------- Mark Empson administrator
Skype Contact = markempson | phone +64 274 363 067 LMPForum | LMP Tech Warehouse | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | LMP Software | Mark Empson Website |
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Apr 5 2010, 10:46 PM
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#5
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Group: Members Posts: 1 Joined: 5-April 10 Member No.: 8,080 |
i do protection relay testing and use a current injection set called sverker 760 also have a device known as omicron 256.
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Lo-Fi Version | Time is now: 3rd September 2010 - 07:28 PM |
