1、EIA 473 81 m 3234600 0070738 7 m /- STANDARD ANSI/EIA RS-473 1981 APPROVED JULY 2, 1980 EIA STANDARD c) b * M EIA/NARM STANDARD DEFINITIONS Ly -3.-_-_- 1. . - -. , .-_ . -. I I CONTACT CURRENTS SHQUN (.E.OU)- I ARE AS FOR NON-IHDUCTIYE LOADS )PEN OR AT NORHAL “DYNAMIC RESISTANCE“ QR FORH. -A OR RORM
2、ALLI OPEN (HAKE) CONTACT - FINAL ACTUATION TIHE ;_I CONTACT CURRENT I I CONTACT CURRENT BREAK CONTACT CLOS TRANSFER (UREA%* u flAKE) CONTACTS “DYNAMIC RESISTANCE“ i+nn n OR “GRASS“ INITIAL ACTUATION - HAKE CONTACT CLOSED TIME , 1 $u eouNc6 “ T M - OPERATE TIME TRANSFER TiME 4 I- FINAL ACTUATION TIME
3、 11 TIHE - .-t $. “ FIGURE 6 Time Traces Typical of Relay Pickup - EIA 473 BL m 3234600 0070753 3 m CONTACT ClDSED EIA/NARM STANDARD RS-473 Page 13 FORM A OR -. I HAY. OR RAY I NOT, EXIST) (HAKE) CONTACT I OPERATED RELAY COIL CURRENT - FINAL ACTUATION TIME+ TKKE COIL CURRENT CLOSED, w =o 1- cc 4- xv
4、r en. ao *z *% -te the actual measured dropout value of a particular relay lies within these limits. 8.4 Time Sequence in Operate and Release Figures 6 and 7 show the sequence of events in relay pickup and dropout with respect to coil current, armature motion, and contact actuation. Contact current
5、is shown for resistive loads for three contacts: one normally open, one normally closed, and one a break-make. 8.4.1 Operation Starting with the time the coil circuit is closed, the coil current increases at a decreasing rate. In the latter part of the stroke it may or may not decrease momentar- iy,
6、 but in any case shows a discontinuity when the armature seats, after which it increases gradually to the steady-state value, The armature motion starts after an interval, the waiting time, in which the pull developed by the coil and the armature assembly exceeds the spring forces. Armature velocity
7、 generally , increases throughout the stroke. Contact actuation occurs during the arma- ture stroke. A normally open contact may show bounce which can continue after the armature seats. The final actuation time exceeds the initial actuation time by the bounce time. A normally closed contact usually
8、shows no bounce on opening, but the contact current may show arcing or other transients. With a break-make contact the interval between opening of one contact and closure of the other is the transfer time. 8.4.2 Release The coil-current curve during dropout depends upon the circuit used. After the c
9、oil.circuit is opened, there is a waiting-time interval before the armature moves, corresponding to the time required for the pull to decrease to a value equal to the operated load. The armature gene- rally moves with increasing velocity until it strikes the backstop; the return motion following thi
10、s impact is the armature rebound. t - AWPERE-TURNS FIGURE 8 Operate-Time Relations FIGURE 9 Operate-Time Characteristic *EIA 473 AL 3234b00 0070755 7 = Contact actuation occurs durinq the return 0 stroke. may show bounce (reclosure) as a result of armature rebound in which case the final actuation t
11、ime exceeds the initial actua- tion time by the bounce time. A normally closed contact usually shows bounce in closure on dropout. As in pickup, the transfer time of a break-make is the inter- val between opening and closure of the two contacts. A normally open contact in dropout EIA/NARM STANDARD R
12、S-473 Page 15 adjustment - The modification of any or a+l of the elements of tension, shape, or posi- tion of relay parts (to affect one or more of the operating characteristics or to meet mechanical requirements), for example, adjustments of armature gap, restoring spring force, contact gap, or con
13、tact force. air gap - See gap, armature; gap, contact; gap , heel. 8.5 Operate-Time Characteristic airline - See gap, heel. For a given relay and a given load, the op- erate time varies inversely with the applied power and ampere-turns, e.?., Figure 8. For a constant value of coil-circuit power and
14、with ampere-turns increasing over the measured pickup value, the operate time decreases, passes through a minimum, and increases at higher values of ampere-turns because of the corresponding increase in inductance. The operate time characteris- tic is obtained by plotting (on logarithmic paper) the
15、minimum operate times (optimum values of ampere-turns) against power as shom in Figure 9. Operate time varies in- versely with power initially, inversely as the cube root of the power at higher levels until the structure approaches magnetic saturation, at which the operate time becomes limited to th
16、at for the mechanical motion corresponding to the pull developed by the saturated structure. e 9. DEFINITIONS Definitions as given herein apply specifi- cally to the subject treated in this stan- dard. Power relays are covered by ANSI-C37 Standards. ANSI/IEEE Standard 100-1977, IEEE Standard Diction
17、ary of Electrical and Electronics Terms was approved May 12, 1978, and uses many of the definitions of this work. IEC standards have been surveyed. One work has been specifically taken into account: International Electrotechnical Vocabulary Chapter 446: Electrical Relays Publication 50 (446) 1977 Fo
18、r the benefit of the users of this stan- dard some of the IEC definitions have been included in this work and, where given, are identified with the term, IEC, after the definition. actuating card - See card, armature. actuating system - See actuator. actuator - The parts of a relay that convert elec
19、trical energy into mechanical work. add-and-subtract relay - See relay , bi- directional. ampere-turns - The product of the number of turns in an electromagnetic coil winding and the current in amperes passing through the winding. On ac, the rms current value is generally used in the product of curr
20、ent and turns and is referred to as rms ampere- turns. (See 9.2. ) antifreeze pin - See residual, screw, pin, plate, stud, or shim. arm, armature - (1) The protrusion or lever on some types of armature employed to actuate the associated contact spring pileup. (2) The moving part or parts of a reed s
21、witch. arm, contact - A current carrying protru- sion, resilient or nonresilient, onto which contacts may be fastened. Also see spring, contact. armature - The moving magnetic member of an electromagnetic relay structure. armature, balanced - A relay armature that rotates about its center of mass an
22、d is therefore approximately in equilibrium with respect to both gravitational (static) and accelerative (dynamic) forces. armature contact - See contact, movable. armature, end-on - A relay armature whose principal motion is parallel to the longi- tudinal axis of a core having a pole face at one en
23、d. armature, long-lever - An armature with its contact-actuating arm greater in length than the distance from the armature hinge, bearing, or fulcrum to the portion of the armature opposite the pole face. armature, plunger, or solenoid - A relay that moves within a tubular core in a direc- tion para
24、llel to its longitudinal axis. armature residual gap - See gap, residual. armature, short-lever - An armature with its contact-actuating arm length equal to or less than the distance from the armature hinge, bearing, or fulcrum to the portion of the armature opposite the pole face. EIA 473 81 = 3234
25、600 O070756 9 EIA/NARM STANDARD RS-473 Page 16 armature, side, or armature, flat - A relay armature whose motion is perpendicular to the longitudinal axis of a core having a pole face at one side. armature stroke - See travel, armature. armature stud - See buffer, armature. back contact - See contac
26、t, normally closed. backstop, armature - That part of the relay which limits the movement of the armature away from the pole face or core. In some relays a normally closed contact may serve as the backstop. bank - One or more contact levels of a stepping switch. - bar - See card, armature; relay bar
27、. bearing, armature - The point at which the armature bears against the heelpiece (ful- crum) or the member securing the armature to the relay. (See also hinge, armature.) an overcurrent or an undercurrent relay, or a combination of both. relay, dashpot - A relay employing the dashpot principle to e
28、ffect a time delay. relay, delay - See relay, time delay. relay, dependent-time measuring - A speci- fied time measuring relay for which times depend, in a specified manner, on the value of the characteristic quantity. (IEC) relay, differential - A relay with multiple windings that functions when th
29、e voltage, current, or power difference between the windings reaches a predetermined value. relay, direct current (dc) - A relay de- signed for operation from a direct current source. relay, double arm - A relay with two pile- ups, each actuated by a separate armature arm. relay, electrical - A devi
30、ce designed to produce sudden, predetermined changes in one or more electrical output circuits, when certain conditions are fulfilled in the electrical input circuits controlling the device. (IEC) Note 1 - The term relay shall be re- stricted to a relay unit having a single relaying function between
31、 its input circuits and its output circuits. Note 2 - The term relay includes all the components which are necessary for its specified operation. Note 3 - The adjective “electrical“ can be deleted when no ambiguity may occur. relay, electrical interlock - See relay, interlock. relay, electromagnetic
32、 - A relay whose ope- ration depends upon the electromagnetic ef- fects of current flowing in an energizing winding. relay, electromagnetic time delay - A relay in which the actuation of the contacts is delayed by the inductive effect of a con- ducting sleeve or slug (usually nonmagnetic) or a short
33、-circuited winding over the core. relay, electromechanical - An electrical relay in which the designed response is developed by the relative movement of mechanical elements under the action of a current in the input circuits. (IEC) ! relay, electrostatic - A relay in which op- eration depends upon m
34、otion of two or more insulated conductors caused by electro- static effects. relay, electrostrictive - A relay in which operation depends upon the dimensional changes of an electrostrictive dielectric. relay, enclosed - (1) hermetically sealed - A relay con- tained within an enclosure that is sealed
35、 by fusion or other comparable means to ensure a low rate of gas leakage. (Gener- ally metal-to-metal or metal-to-glass sealing is employed. 1 (2) encapsulated - A relay embedded in a suitable potting compound. (3) sealed - A relay that has both coil and contacts enclosed in a relatively airtight co
36、ver. (4) covered - A relay contained in an un- sealed housing. Note - The coil and contact assemblies may be separately enclosed and isolated from each other by various combinations of the above enclosures. relay, ferreed - Coined name for a special form of dry reed relay having a return mag- netic
37、path of high remanence material that provides a bistable contact. relay, flasher A self-interrupting relay, usually of the thermal or solid state type * relay, frequency sensitive - A relay that operates when energized electrically at a particular frequency or within specific frequency bands; for ex
38、ample, a resonant- reed relay. relay, homing - A stepping relay that re- turns to a specified starting position, home, prior to each operating cycle. relay, hot-wire - A relay in which the operating current flows directly through a tension member whose thermal expansion actuates the relay. relay, hy
39、brid electromechanical - A relay in which electromechanical and electronic devices are combined to perform switching functions with an electromechanical output. relay, hybrid solid state - a relay in which electromechanical and electronic devices are combined to perform switching functions with a so
40、lid state output. relay, impulse - (1) A relay that follows and repeats pulses, as from a telephone dial. (2) A relay that operates on stored energy of a short pulse after the pulse ends. (3) A relay tha-t discriminates between length and strength of pulses, operating on short or weak ones. (4) A EI
41、AJNARM STANDARD RS-473 Page 25 relay that alternately assumes one of two positions as pulsed. relay, independent-timer measuring - A specified time measuring relay the speci- fied time for which can be considered as being independent, within specified limits, of the value of the characteristic quan-
42、 tity. (IEC) relay, inertia - A relay wlth added weights or other modif icationc that increase the moment of inertia of its moving parts in order either to slow its operation or to cause it to continue in motion after the energizing force ends. relay, instrument - A sensitive relay in which the prin
43、ciple of operation is similar to that of instruments such as the elec- trodynamometer, iron vane, galvanometer, and moving magnet. relay, integrating - A relay that operates on the energy stored from a long pulse or a series of pulses of the same or varying mag- nitude, for example, a thermal relay.
44、 relay, interlock - A relay with two or more armatures having a mechanical linkage, or an electrical interconnection, or both, whereby the position of one armature per- mits, prevents, or causes motion of another. relay, intermittent-duty - A relay which must be de-energized at intervals to avoid ex
45、cessive temperatures, or a relay that is energized at intervals, as in pulsing. relay, latching - A relay that maintains its contacts in the last position assumed with- out the need of maintaining coil energiza- tion. (1) magnetic latching - A relay that re- mains operated, held by either remanent m
46、agnetism in the structure or by the influence of a permanent magnet, until reset. (See also relay, polarized bistable. ) (2) mechanical latching - A relay in which the armature or contacts may be latched mechanically in the operated or unoper- ated position until reset manually or electrically. rela
47、y, lockup - See relay, latching. relay, magnetostrictive - A relay in which operation depends upon dimensional changes of a magnetic material in a magnetic field. relay, manual reset - A relay that may be restored manually to its unoperated posi- tion. relay, marginal - A relay that functions in res
48、ponse to predetermined changes in the value of coil current or voltage. EIA 473 BL 3234b00 00707bb L W ElA/NARM STANDARD RC-473 Page 26 relay, measuring - An electrical relay intended to switch when its characteristic quantity, under specified conditions and with a specified accuracy, attains its op
49、erating value. (IEC) relay, mechanical time delay - A relay in which operate or release action is delayed by a clockwork, escapement, bellows, dash- pot, or other mechanical device. relay, memory - (1) A relay having two or more coils, and a set of contacts that re- main in a position determined by the coil last energized. (2) Sometimes used for a latching relay. relay, mercury contact - (1) Mercury wetted contact - a form of reed relay in which the reeds and contacts are glass enclosed and are wetted by a film of mercury obtained by capillary action from
