1、FORD MANUFACTURING STANDARDS EL3 DECEMBER 1993 PROGRAMMABLE CONTROLLERS - REQUIREMENTS EL3 Page 1 1. SCOPE: 1.1 This standard describes the requirements for programmable controllers (PCs) with greater than 64 inputs and outputs (I/O) and greater than 1000 words of memory intended for general use thr
2、oughout Ford Motor Company which will promote: (1) Safety to personnel. (2) Uninterrupted production. (3) Long life of equipment. (4) Ease and low cost of maintenance. 1.2 1.3 1.4 This standard includes and supplements the requirements of NEMA ICS 3-304, “Programmable Controllers“, and as applicable
3、, requirements in: . ANSI/IEEE C37.90.1, “Standard Surge Withstand Capability (SWC) Tests for Protective Relays and Relay Systems“ . ICS l-109.6, “Electrical Noise Tests“ (Showering Arc) . Ford Manufacturing Standard EL3X, “Programmable Controllers - Applications“ . Ford Manufacturing Standard ELX,
4、“Electronic Standards for Mass Production Equipment and General Purpose Machine Tools“ . Ford Manufacturing Standard EXl, “Electrical Standards for Mass Production Equipment“ Use of the word “shall“ herein is understood as a requirement; the word “should“ as a recommendation. Deviations from this St
5、andard shall have the approval of the requisitioning activity in writing. Any waivers granted shall apply only to the order in question and shall not be considered as permanent. 2. GENERAL: 2.1 The PC shall operate in compliance with this standard over a supply voltage range of 85% to 110% of the no
6、minal 120 VAC supply at 50/60 Hz, +/- 5%. 2.2 Current or voltage transients or electromagnetic effects SHALL NOT cause spurious operation or affect the normal operation of the PC. The PC shall meet or exceed the requirements of ANSI/IEEE C37.90.1 surge withstand capability and NEMA ICS l-109.6 showe
7、ring arc tests. Protection circuitry shall fail to a safe condition. FORD MANUFACTURING STANDARDS EL3 DECEMBER 1993 PROGRAMMABLE CONTROLLERS - REQUIREMENTS EL3 Page 2 I 2.3 2.4 2.5 2.6 2.7 3. 3.1 3.2 PC Functions. The PC shall operate properly in a temperature range of 0 to 60 C (32 to 140 F) measur
8、ed inside the NEMA 12 enclosure in which the PC system will be mounted. It shall be capable of operating continuously at 60 C without additional ventilation or active cooling systems. The PC shall operate properly in a humidity range of 5% to 95% (non-condensing) per NEMA/ICS 3-304.06.01(b). Fastene
9、rs used in maintenance operations shall be of captive designs. Plug-in modules shall be mechanically secured or locked in place. The assembled system shall be designed to withstand vibration testing of 5-10Hz at 0.2 inch displacement (peak to peak) and lo-200Hz at 1 g and endurance testing (sweep te
10、st) of lo-200Hz for ninety minutes per axis and a dwell at resonance frequencies (10 minutes per resonance) per ML Standard 810C and IEC 68-2-6. Where the PC uses similar modules with unlike functions, the modules shall be mechanically keyed to prohibit insertion in incorrect positions or electrical
11、ly interlocked to prevent operation in an incorrect position. CENTRAL PROCESSING UNIT (CPU): In the event of a power failure, the CPU shall be capable of retaining the status or accumulated values in its memory associated with arithmetic operations, data files, latching states and timing functions.
12、Where batteries are used for memory retention, see 3.8. 3.2.1 The CPU shall offer a minimum function menu consisting of ladder programming including: a) Basic Relay b) “Latching“ or “Retentive“ Relay c) Retentive Timing d) Non-retentive Timing e) Incremental Counting 3.2.2 The basic instruction set
13、should be capable of providing number comparisons, four (4) digit arithmetic operations, decremental counting, shift registers, block operations, intelligent inputs and outputs (I/O) such as thermocouple and ASCII, immediate I/O, PID, subroutine, skip and real time clock. FORD MANUFACTURING STANDARD
14、S EL3 DECEMBER 1993 PROGRAMMABLE CONTROLLERS - REQUIREMENTS EL3 Page 3 3.2.3 The PC should be capable of communication with peer level PCs and host or master PCs, or computers via an RS-232-C interface port or similar data port. These data ports shall be separate from any required by a local hand-he
15、ld or built-in data access panel or the programming devices. 3.2.4 3.2.5 3.2.6 3.3 3.4 3.5 3.6 3.7 3.8 BATTERIES: 3.8.1 Where a battery is required to retain the PC memory, an internal contact or output, operating as part of the CPU and an indicating light, shall be available to indicate that the me
16、mory support battery is low. 3.8.2 The logic line shall accept a minimum of seven (7) elements in series and a minimum of four (4) in parallel. Program saving to a remote device shall default to include the entire control program memory. Programming instructions for the smallest controllers should b
17、e a subset of the largest for full upward compatibility. The PC shall not increment/decrement counters nor otherwise cause false movement or change in retained data when the power is turned on or off. The PC manufacturer shall be responsible for providing adequate Self-Diagnostic routines to insure
18、the safe and reliable operation of the entire system (PC and I/O). Upon fault detection, output devices shall be capable of being selected to be de-energized or held in last state (necessary in PID or analog control). Status indicating lights on the CPU shall verify normal operation. Typical indicat
19、ions are: AC and DC power, processor cycling, parity error, memory fault, memory support battery low, processor fault, power supply fault, transient suppressor circuitry fault and I/O fault. Error Detection and Fault Isolation (EDFI) shall be integral and shall localize faults to the lowest modular
20、(plug-in) level. Local fault annunciation via lights, and program accessible status bits shall be available. Where a battery is required to retain PC memory, it shall be replaceable without loss of memory (with power on). The battery shall be a readily available, long life (90 day minimum) type. FOR
21、D MANUFACTURING STANDARDS =- EL3 PROGRAMMABLE CONTROLLERS - REQUIREMENTS DECEMBER 1993 = EL3 Page 4 3.8.3 The low battery indicator should function a minimum of 14 days prior to final battery failure. 3.9 A selector switch shall be furnished to allow programming or editing only in the program or pro
22、gram/run position. The selector switch shall be of the key lock type with the key removable in any position. Two keys shall be furnished. 3.10 Removal of any processor module shall shut down the PC system. 4. PROGRAMMING AND DATA ACCESS: 4.1 Programming devices shall provide indication of the logic
23、state of each element comprising a rung or network of logic. 4.2 MAIN PROGRAMMING DEVICE: 4.2.1 The main programming device shall display all elements, including pre-set and accumulated values, comprising a rung or network of logic simultaneously and should provide capability of displaying system gr
24、aphics, The main programming device shall lend itself to be utilized as a universal programmer and be up and down compatible with vendors entire line of PCs and lock out non-supported features. It should be directly i compatible with a standard off the shelf IBM PC. 4.2.2 The main programming device
25、 shall provide a means of program entry, editing, searching by function and address, timer and counter presetting, and monitoring, and should support password codes and “histogramming“. 4.2.3 The main programming device shall incorporate a cassette, cartridge, or disc recorder for loading, recording
26、, programming and verifying PC programs both on and off line. 4.2.4 The main programming device shall indicate during programming when an output or register address has been previously used. 4.2.5 The main programming device shall be capable of connecting to the programmable controller in any mode.
27、4.3 The PC shall permit loading, recording, and verifying PC programs with the main programming device specified in 4.2.3. 4.4 A computer interface and data handling capability shall be available and programmable with the main programming device. The following features shall be included: FORD MANUFA
28、CTURING STANDARDS EL3 PROG-LE CONTROLLERS - REQUIREMENTS EL3 DECEMBER 1993 Page 5 - - a) Computer Interface 1) Monitor and control of words or bits in the I/O data and data table of the PCmemory. 2) Load a program into the PC memory. 3) Produce a list of the total content in the PC memory. 4) Should
29、 conform to Manufacturing Automation Protocol (M.A.P.). b) Data Handling 1) Provide file manipulation. 2) Provide report generation. 4.5 A hand-held or built-in data access panel for examining data and changing preset values should be available. 4.6 PC systems, using remote I/O, shall permit monitor
30、ing and programming from all I/O locations with the main programming device. Interlocking shall not allow more than one programming device to communicate with the CPU at one time for program changes. 4.7 The PC system shall be capable of programming and testing with the power disabled to all output
31、loads. 5. INPUT/OUTPUT (I/O): 5.1 I/O modules shall include a permanent nameplate listing the manufacturers name, the module model number, serial number and the voltage and current ratings. 5.2 I/O modules shall have a status indicating light for each I/O point. An input indicating light shall be co
32、nnected on the field side, prior to conversion to PC level voltage. An output indicating light shall be connected across the output terminals (field side) _ and shall function normally without the load external to the P.C. 5.2.1 I/O module to CPU communication status should be furnished. 5.3 I/O mod
33、ules shall include a quick disconnect means for fast and easy card removal without the necessity of disconnecting field wiring. 5.4 I/O terminals shall accommodate at least two MTW, 19 strand conductors, AWG 16. The conductor strands shall be clamped between two non-rotating surfaces. Saddle or pres
34、sure plates shall be captive to the terminal screw. Neither the head nor the point of the terminal screw shall bear directly on the conductor strands. Screws shall not be smaller than No. 6/32 and should be captive to the terminal base. m 9007Lb0 LlCl53489 3b3 - FORD MANUFACTURING STANDARDS EL3 PROG
35、RAMMABLE CONTROLLERS - REQUIREMENTS EL3 DECEMBER 1993 Page 6 Sufficient space adjacent to each I/O terminal shall be provided to list at least six alphanumeric characters. This space shall not be on the I/O module. 5.6 Inputs and outputs shall be electrically isolated from the controller logic circu
36、itry and from other inputs and outputs. Optical isolation is preferred. 5.7 5.7.1 5.8 5.9 5.10 5.11 I/Os shall be rated either 120 VAC, SO/60 Hz or 24 VDC as may be specified by the requisitioning activity. Sink Inputs and Source Outputs shall be used for 24 VDC; other types are not acceptable. Anal
37、og to digital (A to D) inputs and outputs (D to A) shall be rated to comply with the system requirements. I/Os should be provided with an integral power supply to provide I/O logic and special function reference voltages. 120 VAC SO/60 Hz inputs shall not turn on and shall turn off with 2.2 mA rms o
38、r less of current and shall conduct at least 6 mA rms in the on state. Each AC output shall be rated not less than 2 A continuous and shall be protected by an individual overload device. A visual fault indication shall be provided. Fuses shall be replaceable without soldering and should be accessibl
39、e without the need to remove covers attached with threaded fasteners. I/O modules should not be damaged by removal from, or insertion into, a PC when the system power is on and the field power is off. The following types of I/O should be available. . AC/DC (120V) . AC/DC (240V) . DC (12-24V) . DC (2
40、4-48V) . TTL (5V) . Contact Output . Thermocouple . Analog (0-SV, 0-lOV, -lOV to +lOV) . Analog (4-20ma) . BCD . High Speed . Single Axis Servo . Isolated . Stepper FORD MANUFACTURING STANDARDS EL3 DECEMBER 1993 PROGRAMMABLE CONTROLLRRS - REQUIREMENTS EL3 Page 7 6. MACHINE, PROCESS AND PROGRAM DIAGN
41、OSTIC AND COMMUNICATIONS CAPABILITIES: 6.1 PCs should be capable of supporting machine/equipment diagnostic systems. The diagnostic system shall: a) be self-teaching via menu driven programming (guide or refresher style). b) not increase processor scan time more than 20%. c) be adaptable to synchron
42、ous, semi-synchronous, and non- synchronous processes. d) identify faults to the level of individual inputs and outputs. 6.2 6.3 6.4 6.5 The acceptability of diagnostic capabilities will be judged on adherence to the above diagnostic system features and the following PC diagnostic program criteria:
43、a) Minimal programming effort. b) Provision of semi-automatic updating of the diagnostic program to account for changes in machine/equipment sequencing and timing. c) Provision for selecting timing deviation allowances. d) Remote I/O structure. e) Distributed system architectures. Fault definition s
44、hall be available to the system Loader/Terminal, laterally via peer-to-peer communications, and vertically within a hierarchical communications network. Data comparison for diagnostics shall be capable at bit, word and block/rung level. Programmable controllers should either comply with Manufacturin
45、g . Automation Protocol (MAP) standards or demonstrate co-existence and capability to interface to MAP networks in the future. Preference will be shown to manufacturers who conform to MAP. PCs should be certified using standard National Institute of Standards and Technology (NIST) conformance tests.
46、 Manufacturers should provide evidence of passing such tests upon Ford request. a) Current installations should conform to MAP version 2.1 minimum. b) Requisitioning activity should be contacted for installations beyond 1986. c) Communications structure shall be ANSI/IEEE-802 broadband or baseband t
47、oken-bus network. FORD MANUFACTURING STANDARDS EL3 DECEMBER 1993 PROGRAMMABLE CONTROLLERS - REQUIREMENTS EL3 Page 8 6.6 Programmable controllers should be capable of direct interfacing to at least eight (8) stations which can monitor and direct its operation. Types of stations include main-frame com
48、puters, process computers, CRT terminals, printers, data storage units and other industrial devices with appropriate interfaces. 7. TRAINING AND SUPPORT DOCUMENTATION: 7.1 The PC manufacturer shall make training services and materials available for engineering, maintenance, and operating personnel.
49、Available materials shall include videotapes and self-paced instruction manuals. 7.2 7.3 7.4 7.5 7.6 The PC manufacturer shall make a detailed trouble-shooting guide available. A block diagram format is preferred. When specified, the system supplier shall make available such diagnostics, programming, schematics, and related data to allow the implementation of a service center by the requisitioning activity. The PC manufacturer shall provide detailed hardware and software manuals that cover installation, application, and programming. The PC manufacturer shall provide 24 hour engineeri
