NCR 7156 Multifunction Printer MICR Operation and Trouble-Shooting Guide B005-0000-1057 Issue A
The product described in this book is a licensed product of NCR Corporation. Axiohm is the registered trademark of Axiohm. It is the policy of NCR Corporation (NCR) to improve products as new technology, components, software, and firmware become available. NCR, therefore, reserves the right to change specifications without prior notice. All features, functions, and operations described herein may not be marketed by NCR in all parts of the world. In some instances, photographs are of equipment prototypes.
MICR Operation and Trouble-Shooting Guide i Preface Use this book as a reference manual and troubleshooting guide when servicing the MICR reader. The book is intended as a guide for service representatives, field engineers, and for anyone who will be installing and servicing the 7156 printer. It can also be used as a reference for service training courses. You must be an authorized, trained service representative to service the 7156 printer.
ii MICR Operation and Trouble-Shooting Guide
MICR Operation and Trouble-Shooting Guide Table of Contents Chapter 1: 7156 MICR Operation MICR Setup and Read Test............................................... 1 Necessary Conditions for MICR Reading ...................... 4 Chapter 2: Troubleshooting Incorrect Document Feed.................................................. 5 Printer Hookup ............................................................ 6 Damaged Document ...................................................
iv MICR Operation and Trouble-Shooting Guide Platen Gap Tightness ................................................ 19 Chapter 3: In-Place MICR Adjustment Setup for In-Place MICR Adjustment ........................... 21 MICR Adjustment............................................................
MICR Operation and Trouble-Shooting Guide v Revision Record Issue Date Remarks A Dec 97 First printing
vi MICR Operation and Trouble-Shooting Guide Radio Frequency Interference Statements Federal Communications Commission (FCC) Information to User This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment.
Chapter 1: 7156 MICR Operation MICR (Magnetic Ink Character Recognition) is a feature of the 7156 printer which transforms the slight magnetic properties of specially printed MICR characters into electrical voltage patterns. These patterns, unique for each of the fourteen different MICR character definitions, are translated into an electronic data image by a decoding program residing in the printer controller.
2 Chapter 1: 7156 MICR Operation Select a MICR encoded bank check or similar document. Make sure that the test document is of high quality and fits the specifications for the printer. 4. Enable MICR reading. MICR reading is normally initiated on command by the host system. For test purposes, MICR may also be enabled at the printer using a diagnostics routine. To enable MICR reading by way of self-diagnostics, do the following: • Set the DIP switches as shown: (Record the current settings first.
Chapter 1: 7156 MICR Operation 3 END ORSE H ERE RESERVED FOR FINANCIAL INSTITUTION USE MICR Characters Underneath LED Guide Slip Table Extended Slip Table Check Orientation 5. Turn on the printer power. 6. Insert the MICR document. Place the document on the slip table with the MICR characters face down and to the right. Slide the document to the right until it lines up against the slip guide (wall). Slide the document toward the back of the printer until the printer begins running. 7.
4 Chapter 1: 7156 MICR Operation • For any MICR document, check for “?” character misreads, and serious misread problems such as “NO MICR CHARACTERS”, substantially garbled translation, or character substitutions. Necessary Conditions for MICR Reading The following section outlines the conditions that affect MICR. Make sure that your printer has been set up and operates within the following guidelines.
Chapter 2: Troubleshooting 5 Chapter 2: Troubleshooting This chapter outlines the causes and solutions for the most common MICR problems you may encounter. If you have checked the setup of the MICR according to the information in the preceding chapter and are still experiencing a problem, use this chapter to help you identify and correct the problem. This chapter covers only MICR-related problems. For all other issues, see the 7156 Owner’s Guide or the 7156 Service Guide.
6 Chapter 2: Troubleshooting Check the following to determine the cause of the problem. Printer Hookup Before document feeding is enabled the printer control program checks for the following: • Internal harness connected to their associated headers • All covers closed • Receipt paper loaded Confirm proper harness hookup, cover closures, and loaded paper. Damaged Document Inspect the document. There must be no holes or notches along the 1” margin on the MICR side of the document.
Chapter 2: Troubleshooting 7 • Reinsert the slip correctly so that the indicator LED turns on. Then pull the slip straight to the left about 1/4 inch. The indicator LED should turn off. (This tests the front LED slip-in sensor.) Top of Printer Back Led Sensor (Blow Air or Wipe Clean w/ Soft Damp Cloth) Front Led Sensor (Blow Air Under Wing to Clean) If the indicator LED does not respond correctly, remove the slip table and open the front cover. Locate and clean the two slip-in sensors.
8 Chapter 2: Troubleshooting Document Inserted Incorrectly Verify that the document is being inserted correctly with the MICR characters face down. See the illustration on page 3. Missing Platen Magnet MICR characters are magnetized as the document feeds into the printer by a magnet mounted in or on the platen. Open the front cover and pass an iron object, such as a steel screwdriver blade, just above the right end of the platen. You should notice a strong tug from the magnet.
Chapter 2: Troubleshooting 9 printer and the monitor, and an angular orientation of the monitor to the printer. Improper System Ground Bonding The metal structures and the logic and power grounds in the printer must be securely bonded together and electrically connected to the system ground at the host. The bonding path includes the communication cable connecting the printer to the host.
10 Chapter 2: Troubleshooting Faulty Read head Print Mechanism Buck Coil Buck Coil Leads Read Head Harness Buck Coil Harness MICR Solenoid Harness To test the MICR read head, locate the buck coil to the right of the read head as shown in the illustration above. Disconnect one lead and repeat the MICR read test. • If the test result is now “NO MICR CHARACTERS,” the read head is faulty. Replace the read head assembly and perform the MICR adjustment. Then repeat the MICR read test.
Chapter 2: Troubleshooting 11 Push Read Head Silicone Fluid Positioning Boss Silicone Fluid MICR Assembly Caution: When replacing the read head assembly, make sure that the cantilever mounting area contains a third locating hole for the positioning boss. This positioning boss was added to newer read head assemblies.
12 Chapter 2: Troubleshooting Degraded Buck Coil Connections Set the printer for the MICR adjustment and print out a few readings. For more information, see “In-Place MICR Adjustment” on page 20. Work the buck coil connections by reaching in to the harness terminals with needle-nose pliers and working each wire back and forth about an eighth of an inch. The wires and connectors are shown in the illustration above.
Chapter 2: Troubleshooting 13 • Read head and buck coil, leads-to-frame: greater than 10 Meg Ohms. Isolate and repair any connection for which the resistance varies from the values above. Reassemble the printer and perform the MICR adjustment. Then repeat the MICR read test. For more information on adjusting the MICR, see “In-Place MICR Adjustment” on page 20.
14 Chapter 2: Troubleshooting J17A MICR Buckhead • J17B MICR Readhead If the test result is not “NO MICR CHARACTERS,” either the amplifier board or the control board is faulty. In single-board printers, the board is a combination amplifier/control board. For dual-board printers the MICR amplifier is a separate board behind the cantilever. (The problem may be the interconnect harness between the two boards in the dual-board system; check to confirm that the harness is properly plugged in.
Chapter 2: Troubleshooting 15 continuous, square contact between the document and the MICR read head. Check the following to determine the cause of the problem. Faulty MICR Solenoid Set the printer DIP switches for MICR adjustment as shown below. (Record the present DIP switch settings first.) Switch 1 ON 2 3 4 5 6 OFF OFF OFF OFF OFF 7 8 ON Don’t Care Press the reset button or press the Online button off and then on again to enable the new settings.
16 Chapter 2: Troubleshooting Suppressed Read head Motion MICR Readhead Printhead Carriage Foam Pad While actuating the Paper Feed button, verify that the read head rises higher than the surface of the pad on the bottom of the print head carriage as shown in the illustration above. Move the print head carriage closer to the read head if necessary to make this determination. If the read head does not rise properly, tear down the printer to remove the interference.
Chapter 2: Troubleshooting 17 Printhead Carriage Bottom View of Carriage Assembly Insert Foam Pad Here Foam Pad To confirm the condition of the foam pad, open the front cover and slide the print head carriage to the left. Press down on the paper feed roll until it clicks and remains open. Remove the slip table and use a flash light if necessary to examine the black foam pad on the bottom, right rear of the print head carriage.
18 Chapter 2: Troubleshooting The read head must maintain a line of total contact with the black foam pad on the print head carriage. To examine the line of contact, remove the cantilever assembly with the read head attached. For more information, see the 7156 Service Guide. Remove the ribbon cassette and move the print head carriage to 1 inch from the right end of carriage travel. Depress the MICR solenoid plunger all the way down; the read head presses against the foam pad on the print head carriage.
Chapter 2: Troubleshooting 19 Bumps on Paper Feed Rolls Front Cover Pressure Roller Feed Roller Open the front cover and slowly rotate the feed and pressure rolls. As you rotate each roll, rub the surface from end to end, checking for bumps or high spots. Remove any significant bumps such as those caused by paper debris buildup. Check both rolls. If bumps have been found and removed, repeat the MICR read test.
20 Chapter 2: Troubleshooting
Chapter 3: In-Place MICR Adjustment 21 Chapter 3: In-Place MICR Adjustment Use this adjustment to the MICR amplifier to provide the most effective interference suppression given the printer environment during MICR reading. The environment includes any large metal surfaces under or near the printer and the CRT monitor. The CRT monitor creates interference through a series of polarized pulses generated by the deflection coils on the sides of the CRT tube.
22 Chapter 3: In-Place MICR Adjustment 4. Press the RESET button or press the Online button off and then on again to enable the new DIP switch settings. Caution: Do not move the print head carriage from the position it was moved to by the printer upon reset. If you should move the print head carriage before or during the adjustment, reset the printer to accurately position the print head carriage. MICR Adjustment Before making the adjustment, one of the printer covers must be removed.
Chapter 3: In-Place MICR Adjustment • For single-board printers (the MICR adjustment pots are visible from the front), raise the front cover and remove both screws as shown above that are securing the plastic trim to the steel frame. Unlatch the restraining tab on the right, inside edge of the cover. Separate the plastic cover trim from the metal frame and set the trim aside. Close the metal frame. • For dual-board printers, remove the printer’s top cover.
24 Chapter 3: In-Place MICR Adjustment Top of Printer Paper Paper Feed Button MICR Read Head Potentiometers Led Front Cover DIP Switch Potentiometer (R8) Potentiometer (R9) Paper Front of Printer Single - Board Printer
Chapter 3: In-Place MICR Adjustment 25 Top of Printer Paper Paper Feed Button Potentiometers Shallow Pot Deep Pot MICR Read Head Carriage Assembly Feed Roll Assembly Dual - Board Printer Led 1. Insert a blank sheet of paper in the slip station covering the MICR read head, but behind the paper feed rollers. See the illustration above that matches your printer. This simulates the presence of a MICR document over the read head. 2. Press and release the Paper Feed button.
26 Chapter 3: In-Place MICR Adjustment Printout Value Meaning “OK” Optimum setting “ABCDE” or “ABCDEF” Maximum acceptable interference “ABCDEFG” and greater Interference too high; repeat adjustment procedure A variation of plus or minus one character from line to line is normal. Greater variation indicates either a poor connection to the buck coil or a faulty read head. For more information, see “Incorrect Printer Installation, Electrical Grounding or Bonding, or MICR Adjustment” on page 8.
B005-0000-1057 Dec.
