On 17 Aug 2007 19:58:41 -0400, Sam Goldwasser
wrote:


You will usually find a copper "shading ring" wrapped around the end
of the
pole piece. The current induced in the shading ring delays the decay
of the
magnetic field long enough to smooth it out between cycles. There is
no
diode or smoothing cap!


In the telephony industry these are known as "slugged" relays. Such
relays have a solid copper slug of a specific length - eg. 1/2" or 1"
depending on delay period required - the same diameter as the coil
itself. The slug could either be at the armature end or the heel end
of the coil depending upon whether a predominantly slow operate or
slow release was required. For ac operation it hardly matters which
end is slugged and if pushed for a part you could use a relay with a
spare winding on it and simply short circuit this winding to produce a
"slugging" effect.