1、P MIL-T-24383A (3) bb 777770b OY22b1 4 L MIL-T-24387A(SHIPS AMENDMENT-3 10 April 1979 SUPERSEDING 7 March 1977 AHENDMENT-2 :41 LI TARY S PECIF ICATION TEMPERATURE MEASUREMENT EQUIPMENT SIGNAL CONDITIONER AND POWER SUPPLY (ELECTRICAL) (NAVAL SHIPBOARD USE) This amendment forms a part of Military Spec
2、ification MIL-T-2438.7A(SHIPS), dated 1 June 1973 and is approved for use by the Naval Sea Systems Couunand and is available for use by all Departments and Agencies of the Department of Defense. PAGE 1 t 1.2.1, delete and substitute: “1.2.1 The classification shall be of the following format, as spe
3、cified (see 6.2.1): (see 1.2.1.1) (see 1.2.1.2) circuits (see 1.2.1.3)“ I Add as paragraph 1.2.1.3: 1.2.1.3 Alarm and re ater circuits. Temperature measurement equipment shall include an alarm circui- Eepszer circuit when needed to support system requirements (see 3.4.2.14 and 3.4.2.15). as follows:
4、 The presence of an alarm and repeater circuit shall be designated Y - Yes - an alarm circuit and repeater circuit are included. N - No - alarm and repeater circuits are not included.“ PAGE 2 3.2tc): Delete “varified“ and substitute “varied“. I PAGE 3 3.2, add as items (e) atid (f): “(e) Actuation v
5、alus. The difference between the temperature at which the (fi Alarm circuit repeatabilit . The ability of the alarm circuit to alarm is actuated and the temperature at which the alarm is deactivated. reprduce the actuation pint and deactuation point. 3.4.2.2, second sentences Delete and substitute:
6、“The output shall be a true current source of 4 to 20 aN, d.c. # 3.4.2.5, line 1: neleta “and span“ and substitute “span and alarm“. The static error band requirement shall be met (see 3.10.1) regardless of external load rosistance variations over a span of O to 250 ohms. PAGE 4 3.4.2.7, delete and
7、substituter “3.1.2.7 Isolation. Input and output circuits shall be isolated from ground.“ FSC 6685 Obtained From GLOBAL,ENGINEERING DOCUMENTS 2625 So.Hickory St. Santa Ana. CA 92707 (71 4)540-9870: (800)854-7179 w Provided by IHSNot for ResaleNo reproduction or networking permitted without license f
8、rom IHS-,-,-# I MIt-T-24387A(SHIPC) AMENDMENT-3 Add as paragraphs 3.4.2.14 and 3.4.2.15: “3.4.2.14 Alarm circuit. An alarm circuit shall be provided which will deenergise a a relay when a settempemis exceeded. closures when the relay is deenergized thereby providing fail-safe operation (i,e., alam s
9、ounds if circuit is inadvertently deactivated). requirements when subjected to the test specified in 4.8.16: The relay shall be wired to provide contact The alarm circuit shall meet the followinq ia) Set point accuracy - plus or minus 2 percent of span. (b) (c) Actuation value (see 3.2) - 2 percent
10、of span, (d) Alarm circuit repeatability (see 3.2) - 0.3 percent of span. (e) Relay - The relay used in conjunction with alarm circuit shall be at least Set point range of adjustment - 40 to 90 percent of span, 2 pole double throw having a minimum continuous contact rating of 115 volts, 60 Hz, 5.0 a
11、mperes, resistive. “3.4.2.15 Re eater circuit. The static error band (see 3.2) and repeatability of The circuit shall be so the repeater circhlm specified in 3.10.1 for up to two additional indicators (repeaters) during the various conditions specified in 4.8.17. designed that the failure of the pri
12、mary indicator or any of the repeaters or an open circuit to the primary indicator, or any of the repeaters shall not affect the others. Terminals or an h/N type connector shall be provided on the signal conditioner/pcwer supply (SC/PS) to connect the repeaters.“ 3.5.1.1, add: “Oo to 700F“, 3.5.2.1,
13、 add: “Oa to 700OF“. PAGE 7 3.7.4, item (a) (2) d. 7 and 8: Delete “50aC“ and substitute “65.C“. PAGE 10 3.10.9, line 23 Delete *0.04 percent per degree Fahrenheit“ and substitute “0.02 percent per degree Celsius“. PAGE 11 3.10.13, line 2: Delete “between circuits and“. 4.3, add; “Tests shall be con
14、ducted in the order listed in table I.“ PAGE 12 Tables I and II, add the following: n Examhation and tests Requirement paragraph Test paragraph lam circuit operation 3.4.2.14 4.8.16 :epeater circuit operating 3.4.2.15 4.8.17 1 simulate temperature element input.“ Table III, add the following: n Test
15、s Requirement paragraph Test paragraph arm circuit operation Repeater circuit operatiny 3.4.2.15 4.8.17 L/ Smulate temperature element input.“ PAGE 14 4.8,lO.l.l and 4.8.10.1.2, line 3: Delete “superimposed“ and substitute “induced“. 4.0.12, lines 2 and 3: Delete “and between these circuits“. Page 2
16、 of 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-HIL-T-2Ll387A (3) bb 777770b 0922bL7 L MIL-T-24387A (SHIPS) AMENDMENT-3 PAGE 15 c Add as paragraphs 4.8.16 and 4.8.17: - “4.8.16 Alarm circuit operation. The alarm circuit shall be tested for setp
17、oint Temperature shall be decreased after each run and the actuation value accuracy and repeatability by testing the indicator and alarm system at a temperature of 65 percent of span, The test temperature shall be approached three times and the alarm setpoint noted. noted. The setpoint range of adju
18、stment shall be tested at 40 percent and 90 percent of span. Parameters shall be in accordance with 3.10.1. the indicating system amfa! lowing tests conducted with a reference measurement in accordance with 4.8.2 taken at each condition. Short circuit conditions are to be simulated with a shorting b
19、ar in place of the repeater.“ “4.8.17 Repeater circuit o eration. Two electrical repeaters shall be connected to NOTE: The margins of this amendment are marked “#“ to indicate where changes (additions, modifications, corrections, deletions) from the previous amendment were made. This was done as a c
20、onvenience only and the Government assumes no liability whatsoever for any inaccura- cies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous amendment. Preparing activity: Navy-SH (Project 6685-N621) Page 3 of 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
