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Re: why ground an alarm panel.

Subject: Re: why ground an alarm panel.
From: robertlbass@xxxxxxxxxxx
Date: 25 Dec 2005 00:47:28 -0800
Newsgroups: alt.security.alarms
References: <1133823870.190506.37580@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <3vm23mF16jrh2U1@xxxxxxxxxxxxxx>

> Many years ago, telephones were wired with 3 wires. The 3rd was a ground.

I'm not certain but I always thought the inside ground conductor was
for the old "ground start" telephone switches.  Old timers will recall
that a 20+ years ago there were still ground start modules available
for some alarm systems.  Ground start switches (both PBX and telco
switches) required a short to ground to initiate dialing.

Regards,
Robert L Bass
www.BassBUrglarAlarms.com

References:
- why ground an alarm panel.
  - From: autonut843
- Re: why ground an alarm panel.
  - From: Bill

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