Digest, Vol 21, Issue 26 Msg # 6 Motor Controller
SVCatITC at aol.com
SVCatITC at aol.com
Sat Jul 29 11:48:40 EDT 2017
Just one more note on motor controllers.
Wikipedia has a nice discussion on these things ranging from the simple to
If you click on the "contactor" link, there is a good representation pix of
a common contactor,
something similar to what Bill D. might have purchased.
I'll shut up now unless others may want to continue the discussion on this
In a message dated 7/29/2017 12:30:37 A.M. Eastern Daylight Time,
SVCatITC at aol.com writes:
A motor controller, above 1 hp, and usually used on a 3 ph line, is a
It however has, added features of thermal cutouts on each of the phases on
side of the relay. It's normal electrical name is a contactor. The
actuating coil is
usually 120 VAC, however it can be in special cases 24 VAC or 24 VDC.
Some of the reasons it is used is:
1. To start all 3 phases at the same time to the motor.
2. Provide (in some cases) a local START / STOP pushbutton station.
3. Provide trip protection in case of overload or stall of the motor.
4. Allow remote START / STOP capabilities / facilities.
They are usually big and bulky because the contacts are rated to handle
high horsepower inductive current ratings. They also must make and break
quickly to quench the arc over so as not to weld the contacts together.
More questions about this topic are welcome.
In a message dated 7/28/2017 12:16:23 P.M. Eastern Daylight Time,
vcf-midatlantic-request at lists.vintagecomputerfederation.org writes:
Date: Thu, 27 Jul 2017 19:14:27 -0400
From: Evan Koblentz <evan at vcfed.org>
To: Vcf <vcf-midatlantic at lists.vintagecomputerfederation.org>
Subject: Re: [vcf-midatlantic] Museum power / Running bigger machines
Message-ID: <11095b74-0b91-4f41-9828-84e6b181650c at vcfed.org>
Content-Type: text/plain; charset=UTF-8
>> Maybe Martin will provide one to us but I didn?t ask. I found one on
Amazon for $142.00
Well you just posted on the public list which he reads, too. :)
Anyway: what's a magnetic motor controller?
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