1、FORD MANUFACTURING STANDARDS - EC2 - 1 NEMA SOLID STATE TIME DELAY RELAYS EC2 - 1 DECEMBER 1992 ,. . . Page 1 1. SCOPE 1.1 This Standard outlines the requirements for time delay relays which are used in “On Delay“ and “Off Delay“ applications. 1.2 Approved sources shall supply time delay relays to a
2、ccomplish the following: a) ON Delay b) OFF Delay C) ON Delay with Instantaneous Contacts d) OFF Delay with Instantaneous Contacts Time delay relays should be available either in models which are convertible from ON to OFF delay and vice versa, or in the four models listed above. If convertible the
3、means of conversion should not be readily accessible. 2. DEFINITIONS 2.1 For purposes of this Standard a time delay relay is referred to as a timer. 2.2 On Delay - Energizing of the pilot circuit starts the timing period. Upon completion of the timing period the output(s) transfer. De-energizing of
4、the pilot circuit returns the output(s) to the original state and resets the timing circuit. 2.3 Off Delay - Energizing of the pilot circuit causes immediate transfer of the output(s) and resets the timing circuit. De- energizing of the pilot circuit starts the timing period. Upon completion of the
5、timing period, the output(s) transfer, returning to the original state. 2.4 INSTANTANEOUS CONTACTS: Upon energizing of the pilot circuit, the instantaneous contacts transfer; de-energizing of the pilot circuit causes the instantaneous contacts to return to the original state. 3. GENERAL 3.1 The time
6、r shall also comply with requirements of Ford Manufacturing Standards ELX and EX1. In the event of any conflict, this Standard shall govern. FORD MANUFACTURING STANDARDS EC2 - 1 NEMA SOLID STATE TIME DELAY RELAYS DECEMBER 1992 .,:. . EC2- 1 Page 2 3.2 A manufacturer who desires to supply timers unde
7、r this Standard shall submit four identical sample units with instantaneous outputs (contacts) to Ford Motor Company for test and evaluation. These timers shall be assembled using typical production materials and techniques. 3.3 Prior to testing, the manufacturer shall also furnish electrical and me
8、chanical drawings as deemed necessary for application of the timer. A schematic circuit diagram, pictorial layout, and parts list shall be included. Standard trade identification shall be used for all components. 3.4 The Electrical Standards Subcommittee of the Ford Motor Company will determine appr
9、oved timers, Based on conformance to the requirements of this Standard and the test results. . 3.5 Any change in an approved timer will require further evaluation and approval to remain on the approved source list. Changes shall be indicated by a revision of the model or series number. The model and
10、/or series numbers shall be shown on the exterior of the package in which the timer is shipped, as well as on the timer name-plate. 3.6 The timer may include provision for mounting as an attachment to an approved machine tool relay. 3.7 The mounting space required for a timer shall not exceed a maxi
11、mum of 2.19 inches wide, by 4 inches high, by 6 inches deep. See Figure 1 for typical mounting plate, designed to occupy not more than one space on a typical relay mounting track. 3.8 3.9 Adjusting means, indicators, terminals, and mounting screws shall be accessible from the front of the timer. Ter
12、minals on the timer shall accommodate at least two type “W, 19 strand conductors, AWG 16 through 14. The conductor strands shall be clamped between two non-rotating surfaces. Saddle or pressure plates shall be captive to the terminal screw. Neither the head nor the point of the terminal screw shall
13、bear directly on the conductor strands. Screws shall no be smaller than No. 6/32, and of sufficient length so that at least two threads remain engaged when the clamping assembly is open to receive the largest conductor. 3.10 “ON“ delay timers shall include an indicating lamp which should flash durin
14、g the timing period and shall remain lighted upon expiration of the timing period. “OFF“ delay timers shall include a lamp which remains lighted until the pilot circuit is opened; it should flash while timing, and shall extinguish upon expiration of the timing period. See Figure 2 for typical sequen
15、ce of two timing operations. alternatively, two lamps of different colors may be used to indicate the timing and timed out conditions. 4. TIMING RANGE 4.1.1 A timing range of .3 to 30 seconds shall be provided. Multi- ranges are acceptable if the specified range is included. The manufacturer should
16、have other models available with time ranges such as .05 seconds to one second, and three seconds to three minutes. FIGURE 1 - Typical Mounting Plate Ill -8- 3-12 1 ! I 1 I t 3.68 - i6 Gauge Nominal ( .0598) Thick n FORD MANUFACTURING STANDARDS EC2 - 1 NE! SOLID STATE TIME DELAY RELAYS DECEMBER 1992
17、 i. EC2-1 Page 4 4.1.2 The timer delay shall be adjustable by a knob, slotted shaft, thumb-wheel switches, or other Ford approved means. All knobs shall have a brass insert for the set screw. 4.1.3 The scale may be calibrated in time units, or in relative numbers. A graduated time scale is preferred
18、. 4.1.4 A permanent method of locating the adjusting means relative to its pointer and scale shall be provided so that proper location can be readily re-established if the retaining device becomes loose. 4.1.5 A method shall be provided to maintain the adjusting means at . the desired dial setting.
19、See 8.1.3, Vibration Test. 4.2 TIMING ACCURACY: put: 4.2.1 Timing functions shall be repetitive for a given time setting within +/- 3% in the temperature range of OC to 60C (32F to 140F) and within +/- 108 in the range from -29C to OC (-20F to 32F) throughout the life expectancy of the timer as desc
20、ribed in paragraph 8.1.2. 4.2.2 Recycle or reset time shail not exceed 50 milliseconds for any time setting. FIGURE 2 - Delay Sequence - Two Operations Shown A2plieci Voltage LI-= Pilot Contacts P1 - P2 “On“ Delay N.O. OuQut “Off I Delay N.O. Output “Off“ Delay N.C . Outgut I 4 Qp .O Indicator Light
21、 Code On (Transfer of Output) Flashing (Tu) Off (Original State) FORD MANUFACTURING STANDARDS EC2 - 1 NEMA SOLID STATE TIME DELAY RELAYS EC2 - 1 DECEMBER 1992 li . . Page 5 5. ELECTRICAL REQUIREMENTS 5.1 The timer shall operate from a nominal 115v ac (60Hz) or 24v dc system. All components shall be
22、suitable for continuous duty. 5.2 The timer shall operate in compliance with this Standard over a supply voltage range of +/- 10% to -15%. This voltage range may be the result of gradual or instantaneous supply variations. 5.3 Current or voltage transients or electromagnetic interference (MI) caused
23、 by adjacent devices (e.g.: solenoids, transformers, welders or induction heaters), or radio frequency interference (EWI) picked up by wiring connected to the timer shall not cause spurious operation or affect the functioning or accuracy of the timer. Repeatability shall not deviate more than +/- 5%
24、 from the time setting when subjected to the electrical noise immunity tests (except 50 micro second rise time) as outlined in NEMA Standard ICs 2-230.40-45. 6. INPUT REQUIREMENTS 6.1 Two terminals marked L 1 and L 2 shall be provided for the power input to the timer. FIGURE 3 - The timer shall func
25、tion properly using either of the initiating circuits shown. FORD MANUFACTURING STANDARDS EC2 - 1 NEMA SOLID STATE TIME DELAY RELAYS EC2 - 1 DECEMBER 1992 .Ti. . , Page 6 6.2 A pilot terminal marked “P“ shall be provided for initiation of the timer as described in paragraphs 2.2 and 2.3. The pilot c
26、ontact(s) which initiates the. timing circuit shall connect between terminals P and L 1. The timer shall function reliably with up to 0 electro- mechanical contacts, plus one solid state output, connected in series to initiate the pilot circuit at 115 VAC. See typical connections to pilot circuit in
27、 Figure 3. The timer shall function properly when initiated by either circuit. 6.3 “OFF“ delay timers shall not start timing, nor the outputs change state, if the pilot circuit is interrupted for up to 12 msec. by contact bounce, vibration, etc. 6.3.1 . The timed contacts shall not change state fals
28、ely when power is . applied simultaneously to terminals L1 and P. 7. OUTPUT REQUIREMENTS 7.1 Outputs should be electro-mechanical or reed contacts. 7.2 Two timed outputs (contacts) shall be furnished, one normally open and one normally closed, with four terminals to provide complete isolation of the
29、 contacts from each other and all other circuitry. Terminals for timed contacts shall be identified Cl - C2 (NO), and C3 - C4 (NC). 7.3 Timers with instantaneous contacts shall include a minimum of one normally open and one normally closed. Instantaneous contacts shall be isolated from each other an
30、d all other circuitry. Instantaneous output terminals shall be identified C5 - C6 (NO), and C7 - C8 (NC). 7.4 Outputs shall be capable of controlling an inductive load operating on 115 VAC at 2.5 amperes inrush current with a 21% power factor, and 1.2 amperes sealed at 32.6% power factor. Outputs sh
31、all also be capable of controlling typical loads as low as 40 milliamperes at 115 VAC (nominal). 7.5 Leakage current shall not adversely affect the control of low current devices such as reed relays, pilot lights, etc. FORD MANUFACTURING STANDARDS EC2-1 NEMA SOLID STATE TIME DELAY RELAYS EC2 - 1 DEC
32、EMBER 1992 Page 7 I a. RELIABILITY TEST 8.1 LIFE REQUIREMENTS : 8.1.1 Four timers shall be tested at rates up to 150 operations per minute. The output circuits will be subjected to an inductive load as described in 7.4 above, 8.1.2 8.1.3 8.1.4 Timers shall achieve a minimum average life of 13 millio
33、n operations. Any failure prior to 10 million operations will terminate the test. In all cases, tests are terminated at 20 million operations. Timers shall be subjected to vibration, up to 60 Hz in each of three mutually perpendicular axes, with an excursion of .030“ peak to peak. The total loading
34、shall not exceed 5.5 Gs for a maximum of one minute. Normally open contacts shall not close and normally closed contacts shall not open for more than 2 milliseconds during this test. Before timers will be accepted for retest, the supplier shall provide evidence of appropriate modifications or redesi
35、gn which precludes the previous failure. 9. IDENTIFICATION 9.1 The timer shall be equipped-with a name-plate listing the manufacturers name, model or catalog number (also see 3.5) and the date of manufacture. The connection diagramshall be shown on the timer, the nameplate is the preferred location. 9.2 The timer shall be stamped with the date of manufacture, using month and year, e. g. , 4-7.6.
