FR 2950ui angular sensor failure

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • edparham
    Technician
    • Mar 2011
    • 10

    #1

    [Electrical] FR 2950ui angular sensor failure

    Have a Riso FR 2950ui. Good machine, excellent prints. Master count: 8,220. Prints: 1.7 million.

    Problem: leading edge of master sheet won't advance because the loading motor won't activate as diagrammed in timing chart on page 17-2 of technical manual. Have visually observed this: drum clamp drops with master leading edge 2-3 inches short of correct position. Train wreck ensues with snarled master material.

    Tested all relevant systems. Only failure found is the 180-degree angular sensor (Test: 10). The 0-degree sensor tests good (Test: 9). Yes, I made sure to flip the drum clamp.

    Assumption is that the relevant sensor in the IC angular-sensor board has gone bad.

    Have located wiring block midway between sensor board and main board, ID'd wiring in and out (power orange-to-white, ground black to blue, the two sensors in the middle).

    Questions: what kind of signal is the sensor sending to the main board when activated?
    Would it be possible to "hot-wire" the wiring block to send the necessary signal to the main board when needed? Is it possible to obtain a Part No. 017-60016-000 angular-sensor board and replace?

    I have the same sensor board in a nonworking GR machine. Like the FR machine, Test: 9 is good and Test: 10 fails. I assume this board is also bad, but I'm wondering if there's a quirk regarding sensor testing.

    Thanks. Hope I've made sense of this.
Working...