Envelope-to: dave@picks.force9.co.uk Delivery-date: Wed, 14 Sep 2005 15:32:09 +0100 Received: by ptb-mxcore02.plus.net with spam-scanned (PlusNet MXCore v2.00) id 1EFYIx-0007uM-Mr for dave@picks.force9.co.uk; Wed, 14 Sep 2005 15:32:09 +0100 Received: from post.thorcom.com ([193.82.116.20]) by ptb-mxcore02.plus.net with esmtp (PlusNet MXCore v2.00) id 1EFYIx-0007tT-Hv for dave@picks.force9.co.uk; Wed, 14 Sep 2005 15:32:07 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1EFYID-0002nV-8C for rs_out_1@blacksheep.org; Wed, 14 Sep 2005 15:31:21 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1EFYIC-0002nM-85 for rsgb_lf_group@blacksheep.org; Wed, 14 Sep 2005 15:31:20 +0100 Received: from cmsout02.mbox.net ([165.212.64.32]) by relay1.thorcom.net with esmtp (Exim 4.51) id 1EFYlY-0004mF-Go for rsgb_lf_group@blacksheep.org; Wed, 14 Sep 2005 16:01:45 +0100 Received: from cmsout02.mbox.net (cmsout02.mbox.net [165.212.64.32]) by cmsout02.mbox.net (Postfix) with ESMTP id 5BA464C983 for ; Wed, 14 Sep 2005 14:31:07 +0000 (GMT) Received: from ca28 [165.212.11.128] by cmsout02.mbox.net via smtad (C8.MAIN.3.21U); Wed, 14 Sep 2005 14:31:07 GMT X-USANET-Source: 165.212.11.128 IN dibene@usa.net ca28 X-USANET-MsgId: XID962JiNofH0627X02 Received: from [192.168.0.7] [151.46.130.63] by ca28 (ASMTP/dibene@usa.net) via mtad (C8.MAIN.3.25R) with ESMTP id 667JiNofF0344M28; Wed, 14 Sep 2005 14:31:05 GMT X-USANET-Auth: 151.46.130.63 AUTH dibene@usa.net [192.168.0.7] Message-ID: <4328342A.9040203@usa.net> Date: Wed, 14 Sep 2005 16:31:06 +0200 From: Alberto di Bene User-Agent: Mozilla Thunderbird 1.0.6 (Windows/20050716) X-Accept-Language: en-us, en MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <000601c5b922$0e59f410$268cf8d4@standalone> In-Reply-To: <000601c5b922$0e59f410$268cf8d4@standalone> Z-USANET-MsgId: XID667JiNofF0344X28 Subject: Re: LF: Current Transformers (off topic, but expertise probably here) Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-PN-SpamFiltered: by PlusNet MXCore (v2.00) Andy wrote: >The one turn generated about 0.3V RMS from a 240V input, although after some >prolonged testing as a CT, I realised I had got the turns calculation some >way out, but thats by-the-way, (it was actually nearer 5000 than 4000). >That suggested the turns ratio as approximately 4000 turns on the 240V mains >winding. > > Maybe I am missing something, but given that the ratio of primary to secondary voltage is a linear function of the turn ratio, if you compute : 240 / 0.3 = 800, then 800 is the turn ratio. If the secondary has just one turn, shouldn't the primary have 800 turns ? 73 Alberto I2PHD