iSys V12 Thermal Printer - Manual (Page 37)

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Adjusting the latch pins
Occasionally, one or both of the latch pins which secure the plotter lid may loosen and require
adjustment. The positions of the latch pins control the amount of pressure the thermal head
exerts on the paper as it passes over the platen roller. This head pressure affects both plot
quality and paper tracking.
Signs of incorrect latch pin adjustment include:
• Faded patches on one side.
• Ragged paper edges caused by poor tracking.
• No plot visible on media.
When adjusting the latch pins, the objective is to lower the pins enough to create consistent
head pressure across the platen roller. Excessive pressure could adversely affect tracking, plot
quality, and thermal head life. If one side of the plot is faded, adjust only the latch pin on that
side.
1. Remove the side panel as described in this chapter.
2. Hold latch pin with fingers while loosening the two latch pin bracket screws (shown in Figure
7-8) for the side to be adjusted.
3. Adjust the pin by moving it 1/32-inch. Tighten the two latch pin bracket screws.
4. Run a test plot. Repeat steps 2 to 4 until the plot is satisfactory looking for darkness and
consistency from one side of the plot to the other.
5. If a latch pin has to be replaced it should be positioned so that there is 3/16-inch between the
latch pin and the top of the groove in which it is seated, (inserting a 3/16 drill bit can be used for
this measurement). Run a test plot and adjust the latch pins as necessary.
6. Replace the side panel.
Replacing the power switch
1. Remove the right side panel as described in this chapter.
2. Detach the four quick-connect wires observing the location of the wires as shown in Figure 7-
8. AC white and black input wires should be located on top of the switch with the corresponding
switched output wires on the bottom.
3. Squeeze the retaining clips on top and the bottom of the power switch housing while pushing
the switch assembly through the bracket.
4. Replace the power switch, wires and right side panel.
Replacing the AC receptacle
1. Remove the right panel as described in this chapter.
2. Detach the two wires leading from the AC receptacle to the power switch.
3. Remove the ground wire nut (shown in Figure 7-8) from the ground stud, and remove the
wires from the stud.
4. Remove the two AC receptacle mounting screws shown in Figure 7-27. Remove the
receptacle.
5. Replace the receptacle and reverse steps to reassemble.