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vex_robotics_platforms:vex_edr:power_and_electrical:power_expander

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vex_robotics_platforms:vex_edr:power_and_electrical:power_expander [2017/06/04 00:43]
biglesliep added H1 title, typo fixes
vex_robotics_platforms:vex_edr:power_and_electrical:power_expander [2017/06/04 03:44] (current)
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 So what's the point of the power expander, exactly, and why does it have to be set up this way? The main point is that it prevents a team from daisy-chaining batteries together, which would double the voltage available and indeed be an unfair advantage (and at the same time would risk damaging various components). The power expander provides a way to run up to 4 motors (or more, using Y-cables) off of a dedicated second battery. So what's the point of the power expander, exactly, and why does it have to be set up this way? The main point is that it prevents a team from daisy-chaining batteries together, which would double the voltage available and indeed be an unfair advantage (and at the same time would risk damaging various components). The power expander provides a way to run up to 4 motors (or more, using Y-cables) off of a dedicated second battery.
  
-====== Use an Extension Cable ======+===== Use an Extension Cable =====
  
 Just like with the Cortex, teams should use a [[vex_robotics_platforms:​vex_edr:​power_and_electrical:​battery_extension|battery extension cable]] with the power expander. Team 1666 did not use one in their first year because the power expander'​s plug was easily accessible for attaching a battery directly to it so didn't //need// one. At California State Championships,​ one of the wires leading from the device to the plug broke off! Luckily the team at the table next to theirs lent one ASAP and they were off to the races again. But it could just as easily have been a complete disaster. Now the team uses a battery extension cable, which costs $5 to replace if it breaks, not $50 like the power expander. Just like with the Cortex, teams should use a [[vex_robotics_platforms:​vex_edr:​power_and_electrical:​battery_extension|battery extension cable]] with the power expander. Team 1666 did not use one in their first year because the power expander'​s plug was easily accessible for attaching a battery directly to it so didn't //need// one. At California State Championships,​ one of the wires leading from the device to the plug broke off! Luckily the team at the table next to theirs lent one ASAP and they were off to the races again. But it could just as easily have been a complete disaster. Now the team uses a battery extension cable, which costs $5 to replace if it breaks, not $50 like the power expander.
-====== Load Testing ​======+===== Load Testing =====
  
 For those who are interested in some technical specs on the load that can be placed on a power expander, [[https://​www.vexforum.com/​index.php/​7208-ptc-performance-measurements/​0|please read this excellent VEX Forum post]] by the awesome **jpearman**. He did extensive testing on a batch of resistors similar to the ones used in the VEX power expander, and explains how much current they can draw before they trip their internal circuit breaker and turn your motors off. For those who are interested in some technical specs on the load that can be placed on a power expander, [[https://​www.vexforum.com/​index.php/​7208-ptc-performance-measurements/​0|please read this excellent VEX Forum post]] by the awesome **jpearman**. He did extensive testing on a batch of resistors similar to the ones used in the VEX power expander, and explains how much current they can draw before they trip their internal circuit breaker and turn your motors off.
vex_robotics_platforms/vex_edr/power_and_electrical/power_expander.txt · Last modified: 2017/06/04 03:44 (external edit)