Diagnostic Light

How do you wire the orange diagnostic light this year?

Thanks

looks like just two wires. No need to mess with a relay.

http://usfirst.org/uploadedFiles/2009%20Power%20distribution%20diargam.pdf

Yup,
plugs right into the new control system with no relay hook up. Wiring only that’s necessary.

what gauge wire should we be using for that? is 14 awg overkill?

Yes, 14 AWG is overkill. Since it is powered via the Digital Sidecar, and that is protected by a 20A breaker, accoring to <R45> C you need 18 AWG.

what does it mean in the wiring diagram how it has the + split and going into both of the ports on the light? are we supposed to split the wire or just have it go into one or the other?

To get the signal light working properly, you need to short La and Lb as your positive terminal, and use N as the negative terminal. This is the procedure used in 2007, and worked for FRC 41 this year.

You’ll then probably want to splice into a 2 pin connector like one supplied in the kit. You can use a lighter gauge because, according to the DSC data sheet, the RSL pins only supply something on the order of 2A.

-Jeff Erickson, FRC41

Jeff,
The two connections to positive power is so that the light can be controlled by the sidecar. Wired this way, flashing control can be initiated in the sidecar. The light has other uses which take advantage of the control input (third connection) on the light.
I am going out on a limb to suggest #18 wire for the light. I will make some inquiries so watch for a team update addressing this.

Al is right, shorting the La and Lb terminals allow the DSC to control the light.

If you play around with it a bit, you find that when contacting one terminal (I forgot if it is La or Lb), the light flashes with some internal mechanism. When shorting the terminals, the light is steadily on. So, shorting La and Lb allow the pulses from the DSC to flash the light. This allows the “fast flash” (disconnected), the “slow flash” (connected but disabled), and “steady on” (connected and enabled).

Also, our light drew about 1.3A when on.

-Jeff

While that’s a useful bit of information, it’s mostly irrelevant to the question of wire size. You need to choose wire that won’t melt before the circuit protection kicks in to cut off the current. Don Rotolo gave the officially correct answer (18 AWG) based on the breaker protecting the entire Digital Sidecar, though a different answer might be possible based on detailed knowledge of the light driver circuitry.

Per the Digital Sidecar datasheet, the Robot Signal Light is protected by a PTC, at 2.2 amps

For reference - RSL states and meaning doc just posted on NI’s website.

http://decibel.ni.com/content/docs/DOC-3120

Russ