Gunner Asch wrote:

Michael A. Terrell wrote:

The only thing I've ever seen that was even close to a ring circuit
that was legal in the US were old commercial fire alarms with a 10 amp
current loop. It looped back to the alarm cabinet for the adjustable
EOL resistor, and monitoring. In some modes, it was a ring, but the
normal operation was just a loop to the EOL resistor, inside the large
metal cabinet to dissipate the waste heat. A man i worked for right
after high school serviced Edwards and Standard Electric alarms and
school clocks.

Crom but I remember those with distain and contempt. Schools ran them
longer than real people.


Part of that was at the state level. They wouldn't allow electronic
alarms in some states for decades becasue they 'weren't a proven
technology'. Some only changed when they were told that there were no
repair parts for the old systems, and that the existing hardware was no
longer certified by the OEM.


Add some window foil at 5 amps...blink blink..you could watch the ice
and snow melt where the foil on the windows was.


If the glass didn't crack.


Gunner, ran an alarm company for 18 yrs, then managed a Cincinnati Time
3 office company


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Greed is the root of all eBay.