Posted by Ron Pool on 23, 2000 at 7:45 PM:
In Reply to: I-Pac assembly posted by awfea on 23, 2000 at 5:57 PM:
: I know it's a dumb question but how do you connect the grounds to the buttons on the I pac? Do you go gnd-button1-bt2-bt3-etc-gnd or do you go gnd-bt1-bt3 etc with another chain of gnd-bt6-bt7 etc? In other words do you have to have a chain going from one ground to the buttons back to the other ground or do you just connect the buttons one or the other ground?
Either way would work. Going in a ring would have the advantage that if any single ground connection between two switches or between the "end" switches and the I-PAC broke, the buttons would all continue to work. Bob Roberts recommends hooking button grounds up in a loop for just this reason.
Here's what Bob Says on JAMMA Plus document at http://www.dameon.net/BBBB/plus.html:
"Hmmmm...we now have 6 buttons added to the CP & no way to toggle them to ground. Of course, we could just splice into the ground loop already on the control panel, but there is an easier & neater way to do this. First, let me address the key word above that is often overlooked....that key word being *loop*. When wiring up a control panel's ground circuit, rather than running 2 to 4 wires up to the CP for grounding, it is better to run one...you can have a spare ready to go if you want...and make a continuous & closed loop of it. Done this way, you can cut any one of the ground jumpers and still have a fully functioning ground circuit. Saved many a service call over the years."
You can read a lot of other tips from Bob Roberts at http://www.dameon.net/BBBB/ . Don't forget to check his link to his parts page -- he seems to have some good deals.
-- Ron