PAXI - Red Lion Controls - #9

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9 WIRING OVERVIEW Electrical connections are made via screw-clamp terminals located on the back of the meter. All conductors should conform to the meter’s voltage and current ratings. All cabling should conform to appropriate standards of good installation, local codes and regulations. It is recommended that the power supplied to the meter (DC or AC) be protected by a fuse or circuit breaker. When wiring the meter, compare the numbers embossed on the back of the meter case against those shown in wiring drawings for proper wire position. Strip the wire, leaving approximately 0.3" (7.5 mm) bare lead exposed (stranded wires should be tinned with solder.) Insert the lead under the correct screwclamp terminal and tighten until the wire is secure. (Pull wire to verify tightness.) Each terminal can accept up to one #14 AWG (2.55 mm) wire, two #18 AWG (1.02 mm), or four #20 AWG (0.61 mm). EMC INSTALLATION GUIDELINES Although this meter is designed with a high degree of immunity to Electro- Magnetic Interference (EMI), proper installation and wiring methods must be followed to ensure compatibility in each application. The type of the electrical noise, source or coupling method into the meter may be different for various installations. The meter becomes more immune to EMI with fewer I/O connections. Cable length, routing, and shield termination are very important and can mean the difference between a successful or troublesome installation. Listed below are some EMC guidelines for successful installation in an industrial environment. 1. The meter should be mounted in a metal enclosure, which is properly connected to protective earth. 2. Use shielded (screened) cables for all Signal and Control inputs. The shield (screen) pigtail connection should be made as short as possible. The connection point for the shield depends somewhat upon the application. Listed below are the recommended methods of connecting the shield, in order of their effectiveness. a. Connect the shield only at the panel where the unit is mounted to earth ground (protective earth). b. Connect the shield to earth ground at both ends of the cable, usually when the noise source frequency is above 1 MHz. c. Connect the shield to common of the meter and leave the other end of the shield unconnected and insulated from earth ground. 3. Never run Signal or Control cables in the same conduit or raceway with AC power lines, conductors feeding motors, solenoids, SCR controls, and heaters, etc. The cables should be ran in metal conduit that is properly grounded. This is especially useful in applications where cable runs are long and portable two-way radios are used in close proximity or if the installation is near a commercial radio transmitter. 4. Signal or Control cables within an enclosure should be routed as far as possible from contactors, control relays, transformers, and other noisy components. 5. In extremely high EMI environments, the use of external EMI suppression devices, such as ferrite suppression cores, is effective. Install them on Signal and Control cables as close to the unit as possible. Loop the cable through the core several times or use multiple cores on each cable for additional protection. Install line filters on the power input cable to the unit to suppress power line interference. Install them near the power entry point of the enclosure. The following EMI suppression devices (or equivalent) are recommended: Ferrite Suppression Cores for signal and control cables: Fair-Rite # 0443167251 (RLC# FCOR0000) TDK # ZCAT3035-1330A Steward # 28B2029-0A0 Line Filters for input power cables: Schaffner # FN610-1/07 (RLC# LFIL0000) Schaffner # FN670-1.8/07 Corcom # 1 VR3 Note: Reference manufacturer’s instructions when installing a line filter. 6. Long cable runs are more susceptible to EMI pickup than short cable runs. Therefore, keep cable runs as short as possible. 7. Switching of inductive loads produces high EMI. Use of snubbers across inductive loads suppresses EMI. Snubber: RLC# SNUB0000. 4.0 WIRING THE METER 4.1 POWER WIRING AC Power Terminal 1: VAC Terminal 2: VAC 1 2 DC+ DC- + - DC Power Terminal 1: +VDC Terminal 2: -VDC 4.2 USER INPUT WIRING Before connecting the wires, the User Input Logic Jumper should be verified for proper position. If User Input 1 and/ or 2 are wired for quadrature or directional counting, an additional switching device should not be connected to that User Input terminal. Only the appropriate User Input terminal has to be wired. Sourcing Logic Terminals 7-9: + VDC through external switching device Terminal 10: -VDC through external switching device The user inputs of the meter are internally pulled down to 0 V with 5.1 K resistance. The input is active when a voltage greater than 3.6 VDC is applied. COMM 3 2 1 7 8 9 10 USER INPUTS Sinking Logic Terminals 7-9 Terminal 10 The user inputs of the meter are internally pulled up to +12 V with 5.1 K resistance. The input is active when it is pulled low (<0 .9 V). Connect external switching device between the appropriate User Input terminal and User Comm. USER INPUTS 7 1 8 2 COMM 9 10 3 + - V SUPPLY (30V max.) }