1、 MIL-T-24777 m Ob 2004726 348 MIL-T-24797( SH) 22 June 1995 MIL I TARY SPEC I FI CATI ON TACHOMETERS, FIBER OPTIC, (NAVAL SHIPBOARD USE), (METRIC) GENERAL SPECIFICATION FOR This specification is approved for use by the Naval Sea Systems Command, Department of the Navy, and is available for use by al
2、l Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 ScoDe. This specification covers fiber optic tachometers capable of measuring rotational speed for use in Navy shipboard applications. 1.2 Classification (see 6.2). 1.2.1 Desiqnations. The sensor classification shall consist of a
3、series of designations which shall be assigned and listed in the format below. 24797 - X - X - X - X Specification Sensing Input Opto-Electronics Sensor Mechanism Power Module Type Mount i ng 1.2.1.4 1.2.1.1 1.2.1.2 1.2.1.3 Configuration 1.2.1.1 Sensinq mechanism. The sensing mechanism of transducti
4、on shall be designated as fol lows: 1 - Reflection 2 - Beam interruption 3 - Magneto-optic effect 1.2.1.2 Input power. The input power required to operate the opto-electronics module shall be designated as follows: DC - 28 Volts direct current (Vdc) AC - 115 Volts alternating current (Vac) Beneficia
5、l comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 03R42, 2431 Jefferson Davis Hwy., Ar1 ington, VA 22242-5160, by using the Standardization Document Improvement Pr
6、oposal (DD Form 1426) appearing at the end of this document or by letter. AMSC N/A FSC 6040 DISTRIBUTION STATEMENT A. Approved for pub1 ic release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T-24777 E 7777Ob 200472
7、7 2Y E MIL-T-24797( SH) 1.2.1.3 Opto-electronics module. The mounting of the tachometers opto-electronics module type shall be designated as follows: Type A - Bulkhead Mounted (See 3.4.2.1) Type B - Console Mounted (See 3.4.2.2) 1.2.1.4 Sensor Mountino Confiquration. The mounting of the tachometers
8、sensor shall be designated as follows: Mount 1 (See 3.4.14.1) 2. APPLICABLE DOCUMENTS 2.1 Government Documents. 2.1.1 Specifications, standards, and handbooks. The fol lowing specifications, standards, and handbooks form a part of this specification to the extent specified herein. Unless otherwise s
9、pecified, the issues of these documents shall be those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation (see 6.2). SPECIFICATIONS MIL ITARY MIL-S-901 MS3452 MS3456 MI L-C-5015 MIL-E-17555 MIL-S-19622 MIL
10、-S-19622/1 MIL-S-19622/17 - MIL-E-24142 - MIL-E-24142/3 - MIL-M-24794 - Shock Tests, H.I. (High-Impact); Shipboard Machinery, Equipment and Systems, Requirements for. Connector, Receptacle, Electric, Box Mounting, Rear Release, Crimp Contact, AN Type Connector, Plug, Electrical, Rear Release, Crimp
11、Contact, AN Type. Connectors , Electrical , Circular Threaded, AN Type General Specification for. Electronic and Electrical Equipment , Accessories, and Provisioned Items (Repair Parts): Packaging of. Stuffing Tubes, Nylon; and Packing Assemblies; General Specification for. Stuffing Tubes , Straight
12、 , Nylon. Stuffing Tube, Nylon, Size 2: Packing Assemblies for. Enclosures for Electrical Fittings and Fixtures, General Specification for. Enclosure for Electrical Fittings and Fixtures, Submersible, Size 6 by 9 Material , Index Matching, Fiber Optics. ( and shall maintain the required accuracy spe
13、cified in 3.5.1. The fiber optic tachometer shall be a A fiber optic All parts of the fiber optic 3.4.1 rotation through a change in optical properties. sensing mechanism shall consist of two sensor heads. used to transmit and one sensor head shall be used to receive an optical signal (generated fro
14、m the opto-electronics module) across an air gap. Sensor head. The sensor head(s) shall be passive and detect shaft The beam interruption One sensor head shall be 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T-24797 (SH) Neither electrical n
15、or electronic components shall be used in the construction of the sensor head. head(s) shall be as specified 9 see 3.4.14). The confi uration and physical dimensions of the sensor 3.4.2 Opto-electronics module mountinq. The opto-electronics module shall be either bulkhead or console mounted as speci
16、fied (see 6.2). 3.4.2.1 Bulkhead mounted (Tvpe A). The opto-electronics module shall be housed in a junction box in accordance with MIL-E-24142 and MIL-E-24142/3. 3.4.2.2 Console mounted (Tvpe BI. The opto-electronics module shall he packaged in a circuit card which is a modular subassembly of a con
17、trol console. be as specified (see 6.2). Design and test requirements for the opto-electronics module shall 3.4.3 Fiber optic cable. diameter of a 4 fiber cable in accordance with MIL-C-85045. there shall be no less than two times the number of fibers needed for operation of the sensor. (size 2, mil
18、itary- part number M19622/1-002 in accordance with and MIL-S-19622/1) and packing assembly (mi 1 itary part number M19622/17-0001 in accordance with MIL-S-19622/17) in accordance with MIL-S-19622, and an O-ring (military part number M83461/1-214) in accordance with MIL-P-83461/1 and MIL-P-83461, ins
19、talled on each end of the cable to accomplish watertight penetration into the sensor head and opto-electronics module. Exposed single fiber OFCC shall not be used over distances greater than one meter. The length of cable shall be as specified (see 6.2). 3.4.4 Optical fiber. opto-electronics unit an
20、d the sensor head shall be in accordance with For integrity, the cable shall have an outer In the cable The cable shall be supplied with a stuffing tube Optical fiber used to transmit light between the MIL-F-49291. 3.4.5 Fiber optic connectors, receptacles and bulkhead adapters. Fiber optic connecto
21、rs, receptacles or bulkhead adapters used shall be in accordance with MIL-C-83522 and MIL-C-83522/16,17,18 respectively. assembled at both ends of the fiber optic cable between the sensor head and the opto-electronics module. The connectors and receptacles shall be mounted inside the sensor head or
22、opto-electronics module. Connectors shall be MIL-STD-2042 method 5B1 may be used as guidance. 3.4.6 Electrical input power requirements. Nominal steady-state power supply requirements for ac shall be 115 * 8 volts, 60 f 2 hertz (Hz), single phase. Nominal steady-state power supply requirements for d
23、c shall be 28 * 4.5 volts. The tachometer shall meet all performance requirements specified herein while operating with specified power supply voltages and their tolerances. 3.4.7 Output siqnal. The output signal of the tachometer shall be directly proportional to the speed being measured. A means s
24、hall be provided for internal selection (within the opto-electronics module) between the fol lowing output signals: true current source of 4 to 20 milliamperes (M), O to 1 mA, 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-T-24797 = 999990b 2
25、004932 641 MIL-T-24797 (SH) O to 2 mA, O to 5 mA; true voltage source of O to 5 volts (V) or O to 10 V dc; and frequency (including TTL compatibility). A means shall also be provided for internal indication of the output signal selected. The complexity of this adjustment shall be such that one indiv
26、idual working alone is capable of performing this adjustment. The adjustment shall not require electrical disconnection. 3.4.7.1 Current output. The O or 4 mA output shall correspond to the lower speed range value and the 1, 2, 5 or 20 mA output shall correspond to the upper speed range value. The c
27、urrent output shall remain accurate regardless of external load resistance variations over a range of O to 250 ohms. 3.4.7.2 Voltaae output. The O Vdc output shall correspond to the lower speed range value and the 5 or 10 Vdc output shall correspond to the upper speed range value. load resistances g
28、reater than 100 thousand ohms. The voltage output shall remain accurate regardless of external 3.4.7.3 Optical output. When an optical output is required, al 1 requirements shall be as specified (see 6.2). 3.4.7.4 Disital output. When an electrical digital output is required, all requirements shall
29、be as specified (see 6.2). The electrical characteristics shall be in accordance with EIA standard RS-422 for balanced voltage digital interface circuitr , or as specified (see 6.2). The data format shall be as specified (see 6.2 1 . 3.4.8 Electrical connectors. A single electrical connector and mat
30、ing plug in accordance with MIL-C-5015 shall be used to interface the input power and 1 inear output signal to the opto-electronics module. connector assembly and pin designations for each of the possible tachometer configurations shall be as fol lows: The appropriate 3.4.8.1 DC input and current or
31、 voltaqe output. The receptacle mounted to the opto-electronics module shall be classification MS3452W14S-5PX in accordance with MS3452. Receptacle pin “A“ shall be positive 28 Vdc power input, pin “B“ shall be negative 28 Vdc power input, pin “C“ shall be case ground, pin “D“ shall be a positive mA
32、 or Vdc signal output, and pin “E“ shall be a negative mA or Vdc signal output. classification MS3456W14S-5SX in accordance with MS3456. The mating plug shall be 3.4.8.2 DC input and frequencv output. The receptacle mounted to the opto-electronics module shall be classification MS3452W14S-5PX in acc
33、ordance with MS3452. shall be negative 28 Vdc power input, pin “C“ shall be case ground, pins “D“ and “E“ shall be frequency signal outputs. The mating plug shall be classification MS3456W14S-5SX in accordance with MS3456. Receptacle pin “A“ shall be positive 28 Vdc power input, pin “B“ 3.4.8.3 AC i
34、nput and current or voltaqe output. the opto-electronics module shall be classification MS3452W14S-5PX in accordance with MS3452. The receptacle mounted to Receptacle pins “A“ and BI shall be 115 Vac power 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IH
35、S-,-,-8 MIL-T-24797 (SH) input, pin “C“ shall be case ground, pin “D“ shall be a positive mA or Vdc signal output, and pin “E“ shall be a negative mA or Vdc signal output. mating plug shall be classification MS3456W14S-5SX in accordance with MS3456. The 3.4.8.4 AC input and frequencv output. opto-el
36、ectronics module shall be an MS3452W14S-5PX in accordance with MS3452. Receptacle pins “A“ and case ground, pins “D“ and “E“ shall be frequency signal outputs. plug shall be classification MS3456W14S-5SX in accordance with MS3456. The receptacle mounted to the shall be 115 Vac power input, pin “C“ s
37、hall be The mating 3.4.8.5 Digital output. The connector assembly for a digital output signal shall be as specified (see 6.2). 3.4.9 RPM ranqe selection. A means shall be provided for internal selection (within the opto-electronics module) between the fol lowing rpm ranges: O - 1000, O - 5000, O - 1
38、0,000, and O - 20,000. A means shall also be provided for internal indication of the rpm range selected. this adjustment shall be such that one individual working alone is capable of performing this adjustment. disconnection. The complexity of The adjustment shall not require electrical 3.4.10 Low i
39、ntensitv alarm indication. The opto-electronics module shall have a red LED which shall light when the intensity of the tachometers optical signal falls below a preset level. The LED shall be located on either the top or-front of the module as it would be mounted during typical usage The LED shall b
40、e visible in typical fluorescent room lighting. opto-electronics alarm will allow for an indication that maintenance is required, prior to a false output signal from the tachometer. 3.4.10.1 Low intensitv alarm set Doint ad.iustment. A means shall be prov for adjusting the low intensity alarm set po
41、int over no less than one half the dynamic range of the tachometer. A means of securing this adjustment shall be provided. The low intensity alarm set point shall be capable of adjustment by one individual without the necessity for any electrical disconnection. Alarm set point adjustments shall be l
42、abeled and shall be accessible when the opto-electronics enclosure cover is removed. The ded of 3.4.11 Sensitivitv adjustment. The tachometer shall have a sensitivity adjustment for increasing or decreasing the electrical pulse height of the optical signal. The tachometers sensitivity shall be adjus
43、table by one individual without the necessity for any electrical disconnection. Sensitivity adjustments shall be labeled and shall be accessible when the opto-electronics enclosure cover is removed. A means shall be provided for adjusting the sensitivity over the dynamic range of the tachometer. of
44、securing this adjustment shall be made. A means 3.4.12 Printed circuit boards. Printed circuit boards shall be in accordance with MIL-STD-1861. 3.4.13 Fuses. The opto-electronics module shall not be fused. 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IH
45、S-,-,-A B MIL-T-24797 (SH) 200.0 Max 50.0 Max 3.4.14 Sensor mountinq conf iquration. The tachometers sensor shall be mounted according to the mount requirement type below (see 1.2.1.4). 3.4.14.1 Mount 1. in table I and figure 1. .OZ kg per millimeter(mm). The dimensions of the mount 1 sensor shall b
46、e as specified The mass per unit length shall be no greater than / I I CABLE 2A THD FiBER r OPTIC I STUFFING -A- TUBE FIGURE l. Sensor head construction. TABLE I. Mount 1 dimensions Sensor head dimensions in mm I 3.4.15 m. opto-electronics module shall be not greater than 5 kilograms. Unless otherwi
47、se specified (see 6.2), the mass of the 3.4.16 Tarqet. The target description including items such as material, size, multiple reflectors and surface features shall be as specified (see 6.2). 3.5 Performance requirements. 3.5.1 Accuracy. The error (see 6.8.1) of the opto-electronics module shall not
48、 be greater than plus or minus 1.0 percent of the output span (see 6.8.2) over an ambient temperature range of 5 to 65C (see 4.7.1). 9 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL -T-24797 ( SH ) 3.5.2 Repeatabil itv. The opto-electronics modu
49、le outputs shall be within 0.5 percent of span during the repeatability test (see 4.7.2). 3.5.3 Reference measurement. The referenced accuracy of each of the output signals of the opto-electronics modwle shall be within plus or minus 1.0 percent of the output span. Measurements shall be made at 10, 50, and 90 percent intervals of span without any alignments or adjustments (see 4.7.3). 3.5.4 Sensitivitv. The ratio of the opto-electronics module o
