Blue Photoreceptor Belt Installation

By Raymond Cote

Over the past year, a number of field support technicians have shown an interest in, and have asked about, the installation of the Xerox blue belts in the Xerox 5090 family of copiers. The Blue Belts are somewhat lower in cost and that may make them a little more attractive for use, and belt life is a little longer. However, installation of the belt could be somewhat tricky unless you perform the proper preparations beforehand.

Presently there are two Blue Photoreceptor Belts in production that are available for use in the field: Xerox part number 1R 538 and the newer Blue Belt 1R575.

If this is a first-time installation of a Blue Belt, there are a number of components that need to be changed in order to make the Blue Belt installation a smooth procedure. Once the copier has been set up, the maintenance should be easy. We have compiled a list of parts and supplies that should be replaced for optimum copy quality results. The cost of each item is a direct quote from Xerox parts; if you shop around, I’m sure you will be able to purchase these items at a considerable savings.

Initial Install Prep

                Before starting this procedure, some housecleaning must be performed. Make sure all HFSIs are performed and the developer has been replaced (if due). Remove the Photoreceptor belt (the brown belt) and vacuum the complete belt module assembly. Check the two segment lamps and ensure that all the lamps are lit in the test mode; if any are not lit, replace the Pretransfer and/or Precharge Erase lamp(s) assembly. Use a soft, moist cleaning cloth to clean the reflectors in the lamp housings. Vacuum the developer housing and the developer bead catch tray area. Use a slightly damp cloth and clean the DSS on the module.

Next, check, clean and examine the following components: (Q901) Belt hole sensor assembly (130K45660), P.R. Ground Brush (115E2200) for missing or worn fibers and (Q902) EFO Shutter Home Sensor (130E460). Use a dry, soft cloth and clean the Electrostatic Voltmeter (ESV), the patch Generator (located over the belt module near the toner bottle) and the Top Edge Erase LED. Check and clean the ID Lens Assembly as well. Remove all five Dicorotrons and clean them with a soft, slightly damp cloth. Rewire all Dicorotrons with the 48K56790 replacement wires, always being careful never to touch the actual wire with your hands. Once again, check and complete all HFSIs that are due. This is especially important in the Xerographic area. As you complete all the HFSI tasks, be sure to reset the counters so that you have an accurate count on these components in the future.

Optics Cavity Checklist

                NOTE of caution: Always wear disposable gloves in the optic area. Never touch the Flash Lamps with your bare hands, as human body oil will contaminate a lamp and cause it to explode in the Flash Lamp Cooling Tube. To be on the safe side, clean the glass flash lamps before you install them with a soft cloth and some Film Remover (43P45).

Remove the Platen glass and examine it for abrasions caused by the RDH document transport belts. If the Platen Glass is kind of beat up, now would be a good time to replace it with a new one. In the field I have seen numerous abraded Platen Glass units causing random Xerographic faults (09-xxx). With power on, select 66% reduction and lower the Cavity Bottom Panel (600K36550). Remove the Cavity Bottom Panel and with a clean, soft slightly damp cloth, clean the white surfaces of the Optics Cavity. Use the drop cloth to protect the belt cavity and lens assembly. Formula “A” is an acceptable cleansing agent (43P48); make sure the Formula “A” never touches the Photoreceptor belt, as it will cause deletions where it comes into contact with the PR Belt.

Now remove and examine the Flash Lamp Shields (55K4312) for discoloration and distortion (from heat). (In the past, I have been able to save them by painting them if they were not damaged or burned too bad.) Remove the Flash Lamp Assemblies and check the glass Flash Lamp Cooling Tubes (52E313); if you are unable to clean them, replace them. Replace the Flash Lamps at this point. When installing the new lamps ensure that the trigger comes into contact with the trigger wire on the glass envelopes of the flash lamps (122E275). Complete the re-assembly of the Flash Lamp Assemblies. Clean the Platen Glass and lens assembly (both sides) with a slightly damp, soft lint-free cloth—or use Lens and Mirror Cleaner (43P81). Never use a commercial or household glass cleaner, as it contains chemicals that will damage the special coating on the Platen glass assembly. Enter “DC-131” (MIN location 169) and reset that location to “100.” This information tells the logic board that you have replaced the Flash Lamps.

                As the fleet of Xerox 5090 copiers starts to age, you will notice the interior of the Optics Cavity is starting to become dirty and the reflective qualities are losing the ability to reflect the flash lamps properly. One of the clues you will notice is constant random system fault shutdowns, with many different 09-xxx codes. When you check the “last 50” shutdown history, don’t be surprised at the several different 09-xxx fault codes recorded—it’s time to repaint the Optics Cavity. In preparation of the new Blue Belt, I would strongly urge you to use the paint kit to brighten up the interior of the Optics Cavity so that it will reflect the maximum amount of light generated from the Flash Lamps.

Restore the Optics Cavity

                Replace the Cavity Bottom Panel, Light Shields, Flash Lamp assemblies and the Platen Glass, and then completely cover the Platen Glass with several sheets of 11x17-inch bright white paper. Restore the Optics to 100% and when you get a “READY” condition enter “DC 904” Preflash Set Up [Flash Faults (Disabled)] [Flash (Disabled)] [Test Display]. Press “Start print”; the Cavity Sensor should read “160 +/- 10.” Adjust the spot on the CAVITY SENSOR PWB if it is not within this range. A clockwise half-turn will lower the value by about 20 bits.

Select “DC-951 PREFLASH” and press “print.” When the Preflash is completed, select “DC-951 Xerographic Setup” program using the special test pattern (82E2770). Make sure the old Brown Belt (1R88) is still installed at this point. Select “Print” and let it run its course. When your 5090 completes the DC-951 Xerographic setup, you can reasonably be assured that you are on the right track and ready for the next step in installing the new Blue Belt. If for any reason the DC 951 Xerographic setup does not reach completion, troubleshoot the system faults and repair them as you go along. Be sure to use your Field Service reference manual to troubleshoot each and every system fault.

                I know it’s kind of late in the procedure to check the Charge Dicorotron Height adjustments, but if you had a problem running the Xerographic Setup procedure (DC-951) now would be a great time to do it. If the 5090 doesn’t have Tag P-235, now would be a good time to order the kit and install it. Kit number 605K5391 was a mandatory retrofit kit. In the kit there were two yellow chopped Dicorotrons (125K1450) and an adjustable Charge bracket assembly. In all reality you need this retrofit in order to make the Blue Belt work. Make sure that you have two yellow Dicorotrons installed in Charge 1 and Charge 2 position.

                Look in the adjustment section for the proper adjustment procedures. If you don’t have the service manual, use a regular paper box (top) for the rough adjustment. Cut a strip of the box top about 6 inches wide and about 17 inches long. Cover the Photoreceptor Belt with a sheet of 20 pound 11x17 paper under the Charge Dicorotrons, slide the cut box top under the charge Dicorotrons, and let the yellow chopped Dicorotrons just touch the box top by adjusting the four screws on the bracket (inboard and outboard). The box top will become a shim to measure the (rough) distance between the Dicors and the surface of the Photoreceptor Belt. The shim tool should have the same amount of drag under the Charge Dicorotrons all around.

                When you run DC-951 you will know if you are in the ballpark by observing the slope. If it’s in range, then the adjustment is correct. If the slope is too high, then you adjusted the Charge Dicorotron bracket assembly too close to the Photoreceptor belt (much too snug on the shim). The adjustment is a little tricky and it’s not an easy one to do, but when it is set up properly (from the beginning) you may never have to touch it again.

                Due to space limitations, we will have to continue the installation of the Blue Belt next month. There are a few NVM MIN values that have to be changed in DC-131 and I will have the list for you then. Meanwhile, if you decide to paint the Optics Cavity, let the customer know they will have to let the paint dry overnight. It is recommended that you apply the first coat and let it dry for two hours before applying the second coat. When I schedule paint jobs, I like to do it on a Friday afternoon—then on Monday morning we can re-assemble the copier and return it to service.

                As always, if there are any questions or concerns about the installation of the Blue Belt, please feel free to contact me.

If you have information that you would like to share with the field, please feel free to submit your ideas to VillageCopierNY@aol.com and I will place your suggestion or fix in the next issue of ENX. From what I hear in the field, it seems that many ex-Xerox technicians miss the field engineering team in Rochester, N.Y. Somehow it was always reassuring to hear a voice on the other end of the phone and a field engineer making a suggestion for a fix on your problem