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  1. Good afternoon, I have a little problem on my hands with some test units I have recently received. PLCs are very new to me.. and I'm learning quickly, so here is some background. I have five test units which are all identical in their control hardware (and I believe in software as well). The units run a SYSMAC C200HS PLC which feeds into a NT30C-ST141B-E HMI. On boot up, three (3) of the test units display "battery lowered" on the first screen.. then it switches to a "connecting to host" screen and stays there. They never leave the "connecting to host" screen.  I went through both the PLC and HMI on each unit and found the HMI's battery was indeed dead. So I replaced that and the units no longer say "battery lowered" and now only shows the "connecting to host" screen.  What's interesting is that the other two (2) units that did not have battery trouble booted right up and opened the home screen of the HMI and allowed me to program and run the test unit as it should. None of the five (5) units have received any programming work or changes since they ran last.. simply a long period of dormancy during which some of the units' HMI batteries died. So I my question is this.. would letting the battery deplete and then replacing it with a fully charged battery cause issues "connecting to host" and if so, where would I start in my trouble shooting process? I am open and grateful to hear any advice on this topic and input you may have based on my situation. Thank you in advance, Ed
  2. At my wits end. I've been challenged with setting up a Test Rack for education, and testing in our electrical shop. I've been attempting to setup a PLC5 1785-L40E processor, with a 1771-A4B Chassis; via serial connection to a Laptop. Seems simple enough? My result is, solid red Proc light. (I assume due to no memory, or EEPROM card installed, however it could be a major hardware fault) No COMM light at all, ever. Auto-Config in RsLinx fails. I've made my own cable according to AB's 1784-CP10 pinout. (null modem) I've tried my laptops serial port(COM1), and a USB to Serial adapter(set to COM4). I've lowered the baud on both ports through Device Manager to 2400. (Default for the processor) Confirmed the stop bit, parity, and Error correcting all match the default parameters. I have the chassis dip switches on the chassis set to all off except for 6 (EEPROM memory does not transfer to processor memory.) I have the processor dip switches set 1 2 3 4 5 6 7 so station number is 1. (I found a publication that states some processors don't recognize 0 as a viable address) U D D D D D D And finally yes I've confirmed that the RS-232C dip switches are set for default configuration. DDDUUDDUDU Also note I have 2 identical chassis', and processors, that I've been experimenting with, as well as a second PC with RSLinx installed. The only difference to note is that one of the processors the Ethernet Stat light periodically blinks red. Because I have two sets of hardware to play with, I find it hard to believe however possible; that both sets of equipment have failed with major hardware faults. This leads me to believe that I am fundamentally missing something here. A step I have missed, or I simply have my head shoved up somewhere... ...any ideas?
  3. Hello all, I am trying to connect a barcode scanner to my plc using a 232C in the serial1. The scanner is a motorolla ls3578 fz, with the following parameters: Transmit code ID: yes Data Transmission format: Data/suffix Suffix: CR(1013) Baud rate: 9600 Parity: none Hard/software handshacking: none Stop bit select: 1 Ascii format: 8 bit RTS Line state: high Prefix: none In order to send data form the scanner to the plc, I use the RXD function block with the following parameters: First receive word: D300 Control word: 0100(hex) Number of bytes: &10 All the communication settings of the PLC are the same that the scanner ones. PROBLEMS 1)When I scan something the scanner beeps as if a transmission error occurs, and the data is ignored. 2)The A392.14 never comes ON and. POSIBLE SOLUTIONS Type of barcode: Now I am using a Code39 barcode. Is it OK? How can I implement the suffix? I have a software that allows me create new barcodes, but I don’t know what kind of data do I need. With 1234567891013 the 1st problem occurs. With 123456789 nothing happens. Communication settings: maybe my communication settings are not well defined. I attach you the file and maybe someone find out an error. Thank you up front! rxd.cxp