Aus telephone voltages and frequencies

[atec77]

On 5/11/2010 3:12 PM, Barry wrote:

On Mon, 18 Oct 2010 16:59:42 +1000, atec77<atec77@hotmail.com> wrote:

On 18/10/2010 4:25 PM, Mark Harriss wrote:
StrandElectric wrote:
Thanks for that, but I've since got the info that the normal nominal
line voltage is 48 volts DC and the ring current is RMS 90 volts at
16.6 Hz, so I guess your figures must be the maximum allowed?


The 90VAC ring superimposed on the 50VDC line gets you about 140V or so
during ringing with whatever voltage the line drops.
which is why on a hot day it zaps ya on a ring when stripping stuff

Back EMF will do that too.

not in the same manner

if you don't know don't bother

--
X-No-Archive: Yes

--
X-No-Archive: Yes

 

[Barry]

On Fri, 05 Nov 2010 16:37:30 +1000, atec77 <atec77@hotmail.com> wrote:

On 5/11/2010 3:12 PM, Barry wrote:
On Mon, 18 Oct 2010 16:59:42 +1000, atec77<atec77@hotmail.com> wrote:

On 18/10/2010 4:25 PM, Mark Harriss wrote:
StrandElectric wrote:
Thanks for that, but I've since got the info that the normal nominal
line voltage is 48 volts DC and the ring current is RMS 90 volts at
16.6 Hz, so I guess your figures must be the maximum allowed?


The 90VAC ring superimposed on the 50VDC line gets you about 140V or so
during ringing with whatever voltage the line drops.
which is why on a hot day it zaps ya on a ring when stripping stuff

Back EMF will do that too.

not in the same manner

Do you know what back EMF is and when and why it occurs?

if you don't know don't bother

Feel free to ask.

--
X-No-Archive: Yes

That won't work there.
Ask someone you trust.