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Unread 28-01-2010, 17:27
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Al Skierkiewicz Al Skierkiewicz is offline
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AKA: Big Al WFFA 2005
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Re: Jaguars, what can we use in FIRST 2010?

Erik,
So as not to confuse, the Victors do not have any sensor inputs or outputs. You can use whatever you would like to monitor motor current, position, speed with whatever sensor you can think of that fits all the other rules, as long as it is external to the Victor.
Joe, another Joe, Joe Ross, is a good reference for the new control system.
As a reminder, the power wiring does contain some resistance that you should add to your calculations. #10 is about .001 ohms/ft., both leads please. (red and black) #12 is .0016/ft. To put it in perspective, a one foot length of #10 wire at 100 amps drops 0.1 volt. This is my definition of the "wire foot" of WF. Four good connections equals one WF, a Jaguar series resistance is 3.3 WF including the current sense resistor (which is in the return lead of the low side FETs). If you use the voltage sense in the Jaguar, you will be more accruate and can forget the resistance between the PD and Jaguar. You will need to add in the resistance between the Jag and motor. Some motors have internal thermal limits that may add some resistance as well as changing resistance with brush wear in. I suggest you mount the Jag close enough to the motor you are controlling that you can use the wiring that is attached to connect directly to the Jag (CIM motor) or as small a connection as possible for the other motors.
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.