Minimum Gauge Wire for Sensors?

[psquared89]

I have searched and I could not find the answer to my question (though, frankly I'm surprised that I'm the first person to ask it...)

I was mounting/wiring the GTS sensor yesterday, and when it came to wiring it, a team member brought an interesting point to my attention. Our team had used an old junk PWM wire to make the temporary connections for testing purposes, but for the final wiring, do we need to use 18 guage wire? The rules state, "Any circuts protected by a 20 Amp breaker need to have at least 18 AWG wire". Do we need to use 18 gauge wire for the little sensors (which couldn't possibly draw more than 100 mA)? Or can we use PMW wire? The boards look like they were made for the PWM wire (the holes on the boards fit the PWM wire pins perfectly), and you can't fit 18 gauge wire through them (soldering, if we must).

If no one here knows the answer, could someone please post the question on the Q & A forum? Our teacher has not been able to log on and we could not post there.

[Pat Fairbank]

<R85> You must use 24 AWG or larger diameter wire for connecting sensors such as: switches, potentiometers,
accelerometers, and other sensors. You must use 24 AWG or larger diameter wire for connecting a Vision
System to Robot Controller inputs, and for extending the PWM cables, for the small muffin fans, or for
wiring LEDs. It is acceptable to use ribbon cable smaller than 24 AWG to connect to the 9 pin ports on the
Robot Controller.
According to rule R85 you can use wire as small as 24 AWG for sensors.

[Al Skierkiewicz]

Pat,
You missed another resource that so many teams miss or just glance over and that is the "First Guidlines Tips and Practices." on the First website. From that document..."As seen in the figure above, two PWM cables are needed to interconnect the module. One cable is
used to supply 12Vdc from the sensor distribution circuit breaker. The other PWM cable connects to
an available digital input on the Robot controller to deliver the sensed pulse counts from the “S” port
and receive +5V from the RC unit. “G” is always the ground connection." Sensors that require 12 volts can be supplied from a common 20 amp fuse by tying all sensor power wires together and using the same 20 amp fuse output per <R91> You must protect the power feed to Custom Circuits and Additional
Electronics with a 20A Circuit Breaker.