👁️‍🗨️Legal Wiring

FRC Wiring requirements can be found in the game manual under the Robot Construction Section.

Some key rules -

Secure the battery. The ROBOT battery must be secured such that it will not dislodge during vigorous ROBOT interaction including if the ROBOT is turned over or placed in any arbitrary orientation.

The ROBOT frame is not a wire. All wiring and electrical devices shall be electrically isolated from the ROBOT frame. The ROBOT frame must not be used to carry electrical current.

Compliance with this rule is checked by observing a >120Ω resistance between either the (+) or (-) post within the APP connector that is attached to the PDP/PDH and any point on the ROBOT. All legal motor controllers with metal cases are electrically isolated. They may be mounted directly to ROBOT frame COMPONENTS. Note that some cameras, decorative lights, and sensors (e.g. some encoders, some IR sensors, etc.) have grounded enclosures or are manufactured with conductive plastics. These devices must be electrically isolated from the ROBOT frame to ensure compliance with this rule

Must be able to turn ROBOT on and off safely. The 120A circuit breaker must be quickly and safely accessible from the exterior of the ROBOT. This is the only 120A circuit breaker allowed on the ROBOT.

Examples considered not “quickly and safely accessible” include breakers covered by an access panel or door, or mounted on, underneath or immediately adjacent to moving COMPONENTS. It is strongly recommended that the 120A circuit breaker location be clearly and obviously labeled so it can be easily found by FIELD STAFF during a MATCH.

Protect circuits with appropriate circuit breakers. Each branch circuit must be protected by 1 and only 1 circuit breaker or fuse on the PDP/PDH per Table 9-3. No other electrical load can be connected to the breaker or fuse supplying this circuit.

Use appropriately sized wire. All circuits shall be wired with appropriately sized insulated copper wire (SIGNAL LEVEL cables don’t have to be copper):

Wires that are recommended by the device manufacturer or originally attached to legal devices are considered part of the device and by default legal. Such wires are exempt from this rule.

In order to show compliance with these rules, teams should use wire with clearly labeled sizes if possible. If unlabeled wiring is used, teams should be prepared to demonstrate that the wire used meets the requirements of this rule (e.g. wire samples and evidence that they are the required size).

Use specified wire colors (mostly). All non-SIGNAL LEVEL wiring with a constant polarity (i.e., except for outputs of relay modules, motor controllers, or sensors) shall be color-coded along their entire length from the manufacturer as follows:

A. red, yellow, white, brown, or black-with-stripe on the positive (e.g. +24VDC, +12VDC, +5VDC, etc.) connections

B. black or blue for the common or negative side (-) of the connections

Exceptions to this rule include:

C. wires that are originally attached to legal devices and any extensions to these wires using the same color as the manufacturer

D. Ethernet cable used in POE cables

Configure devices for your team number. The roboRIO, Driver Station Software, and wireless bridge must be configured to correspond to the correct team number, per the procedures defined in the FIRST Robotics Competition Control System documentation.

ROBOTS must have a signal light. ROBOTS must use at least 1, but no more than 2, diagnostic ROBOT Signal Light (RSL) (P/N 855PB-B12ME522 and/or am-3583). Any RSL must be:

A. mounted on the ROBOT such that it is easily visible while standing 3 ft. (~ 100 cm) away from at least one side of the ROBOT

B. connected to the “RSL” supply terminals on the roboRIO

C. if using the 855PB-B12ME522, wired for solid light operation, by placing a jumper between the “La” and “Lb” terminals on the light per Figure 9-16.

Note: these rules may change slightly season to season. Make sure to reference the Game Manual for a complete and updated list of wiring requirements to construct a legal robot.