You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Glossary<br />
Make - Specified dimension that will cause all front or back contacts to be just made<br />
(closed) when a gauge of this dimension is inserted between the armature residual<br />
screw and core face with the relay energized.<br />
Makes-before-break – (MB) In a dependent front-heel-back contact the front contact will<br />
make before the back contact breaks.<br />
B.2.<br />
GENERAL DEFINITIONS<br />
Approximate - on relay ordering sheets the abbreviation "approx." When used with<br />
armature air gap, it indicates that this air gap is to be adhered to as closely as possible.<br />
In no case should this value be less than the minimums given in Section 1.4 (armature<br />
air gap) of ED60-1.<br />
NOTE<br />
ED60-1 is a generic ED sheet that applies to most relays. It provides<br />
general instructions covering customer adjustments and tests for neutral,<br />
biased-neutral, and polar relays.<br />
Armature Air Gap - The closest point between armature and core face measured when<br />
the relay is energized.<br />
Coil Resistance - This is total coil resistance of relay under test.<br />
Contact Resistance - Total resistance of the individual contact as measured at the<br />
terminals of the relay under test. Resistance to be measured at 1 amp contact current.<br />
Back (NC) measurements made with relay de-energized. Front (NO) measurements<br />
made with relay energized to normal WORKING current.<br />
Down Pressure - Pressure put on fingers so that when contact group is assembled on<br />
relay, all front contacts will be open and all heel contacts will just be making contact with<br />
the back contacts. In addition, each roller must sit on the bottom of its slot when the<br />
pusher is raised to just open the back contacts.<br />
DROP AWAY – (DA) Current or voltage specified on Ordering sheet at which relay just<br />
makes its back contacts. This value is taken after the relay is saturated to a specified<br />
value of current.<br />
Hi-Pot Test (B1 and B2) - The insulation of coils and contacts shall withstand 3000V at<br />
60 Hz.<br />
NOTE<br />
For subsequent tests, voltage should be reduced 20 percent each time.<br />
P1457, Rev. Nov/07 B–2 <strong>Alstom</strong> Signaling Inc.
Change language