VanGardner- -12VoltPower

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I finally had a little free time to look over the last months daily 
reports and I see you are still having some trouble with the -12 volt 
supply tripping out.  I looked at the power distribution page 
and I see this supply feeds the 01A4 gate where the print buffer is 
located.  Then I remembered you sent me some pictures of that gate back 
in April 2006.  When I saw all the red wire on the wiring side I 
wondered what this was as we never used red wire in the USA.  I thought 
someone had installed the Selective Tape Lister feature with this wire. 
 If you look at the card side photo you can see 4 magnet driver cards in 
the 5, 6, 7, 8th position of the left row.
There are two driver circuits per card and these drive the 8 magnets to 
control the rolls of tape in the printer.

On the card side picture I saw the red cable bundle and asked if someone 
could see where it went but things were real busy back then and no one 
had the time.  Looking at the card plug chart for the gate on 
shows a lot of empty sockets where this machine is almost full.  This 
maybe what is overloading the -12 volt supply.  Since you don't have a 
printer with the STL feature maybe some of these cards could be removed 
to reduce the load.  There is a tie down for this feature listed on page  It's on gate 01B1 F02Q to F04L.  F04L is probably a voltage.

The Selective Tape Lister ALDs are on and but I 
don't have any of those pages.  I got these page numbers from the ILDs 
Figure 116 (Carriage Controls 1 and Selective Tape Lister).   I'll bet 
the red cable goes to the 02B8 gate that the printer connectors attach 
to.  This can be seen on  You could also unplug the paddle 
on the red cable at the 01A4 gate.  

Van Gardner

Attached picture

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