Many of the cheap thermal circuit breakers listed under UL 1077
(Supplementary Protectors For Use In Electronic Equipment) are nothing more
than a bimetallic strip. Current is carried through the bimetallic strip
itself. As the current increases, the strip heats up and eventually opens
the contacts. The circuit breakers do have a spring loaded barrier that
moves between the contacts after they open. This prevents the circuit
breaker from resetting automatically and prevents arcing. For limiting
current, a recognized circuit breaker should be used.
In addition, UL 1950 section 1.7.13 refers to thermostats. The standard
allows the thermostat to limit temperature, but they should not be used for
other purposes.
Ted Eckert
Regulatory Compliance Engineer
American Power Conversion Corporation
ted.eck...@apcc.com
The items contained in this e-mail reflect the personal opinions of the
writer and are only provided for the assistance of the reader. The writer
is not speaking in an official capacity for APC nor representing APC's
official position on any matter.
Jim_Bacher@mail.m
onarch.com (Jim To: "Luiz Claudio"
<luizboni...@ig.com.br>, "'emc-pstc'"
Bacher) <emc-p...@majordomo.ieee.org>
Sent by: cc:
owner-emc-pstc@ie Subject: Re:Protection or
Control?
ee.org
09/21/00 09:46 AM
Please respond to
Jim_Bacher
forwarding for luizboni...@ig.com.br
____________________Reply Separator____________________
Subject: Protection or Control?
Author: "Luiz Claudio" <luizboni...@ig.com.br>
List-Post: emc-pstc@listserv.ieee.org
Date: 9/20/00 9:59 PM
I have a question to those who are familiar with the safety requirements
established electrical appliance standards.
A bimetal thermostat is usuallly used to control the temperature of a
certain
ambient within certain limits. Can it also be considered as a protection
device?
I'm not going to give my oppinion to avoid any possibility of biased
answers.
But, please, give your oppinion.
If you have a reference publication which I could use as a reference for a
work
to be presented, please include it in your answer. If not, no problem. Just
give
your oppinion.
Please answer this message to my personal email address:
luizboni...@ig.com.br
Thanks a lot,
Luiz
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
To cancel your subscription, send mail to:
majord...@ieee.org
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Jim Bacher: jim_bac...@mail.monarch.com
Michael Garretson: pstc_ad...@garretson.org
For policy questions, send mail to:
Richard Nute: ri...@ieee.org
-------------------------------------------
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
To cancel your subscription, send mail to:
majord...@ieee.org
with the single line:
unsubscribe emc-pstc
For help, send mail to the list administrators:
Jim Bacher: jim_bac...@mail.monarch.com
Michael Garretson: pstc_ad...@garretson.org
For policy questions, send mail to:
Richard Nute: ri...@ieee.org
