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Changes between Version 12 and Version 13 of ElectricalFrcIntroduction

Timestamp:: Sep 10, 2017, 12:11:04 AM (8 years ago)
Author:: David Albert
Comment:: --

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ElectricalFrcIntroduction

-                      v12
+                      v13
 == Connecting Wires ==
 At many points on the robot, wires must connect to other wires; for example, connecting a motor to a motor controller or a servo motor to a roboRIO.  This is done using a variety of styles of [https://learn.sparkfun.com/tutorials/connector-basics connectors]which consist of metal tabs and clips that can be inserted and removed to conduct electricity; they usually have plastic shells to insulate them and to ensure that the connections are made properly (e.g. the proper wires connected).
+At many points on the robot, wires must connect to other wires; for example, connecting a motor to a motor controller or a servo motor to a roboRIO.  This is done using a variety of styles of [https://learn.sparkfun.com/tutorials/connector-basics connectors]which consist of metal tabs and clips that can be inserted and removed to conduct electricity; they usually have plastic shells to insulate them and to ensure that the connections are made properly (e.g. the proper wires connected).
 The metal tabs and clips must be attached to the wires carrying the electricity and this is usually done by one of several methods:
 …
  * Stripping and soldering: a tool is used to remove some insulation from the wire, the metal portion of the connector is then soldered to the wire using a very hot soldering and solder (a metal that melts at relatively low temperatures).
  * Stripping and crimping: insulation is removed from the wire and a specially made metal connector is compressed onto the wires using a tool; if done properly, the connection is extremely tight and reliable.
  * Insulation displacement: some connectors include sharp pins or blades that are simply pressed into the wire and puncture the insulation making the electrical contact.  These can be secure but are generally only used for low current applications.
  * Stripping and securing: insulation is removed from the wire and the wire is secured using a screw or a lever.
+ * Insulation displacement: some connectors include sharp pins or blades that are simply pressed into the wire and puncture the insulation making the electrical contact.  These can be secure but are generally only used for low current applications.
+ * Stripping and securing: insulation is removed from the wire and the wire is secured using a screw or a [https://www.youtube.com/watch?v=n8gLG6c-iKc lever].
 Commonly used connectors for robotics include:
+ * [https://www.andersonpower.com/_global-assets/downloads/pdf/ds-sb50.pdf Anderson SB50A] connectors are used for the highest-current (up to 120A) connections (usually the battery) with 6-8 gauge wires.  See [https://www.youtube.com/watch?v=RQTjvsnyiDY here]for how to attach the connectors to wires.
+ * [https://www.andersonpower.com/us/en/products/powerpole/index.aspx Anderson Powerpole] PP15, PP30, PP45 connectors used for high-current (up to 15A, 30A, or 45A) connections (usually motors) with 10-12 gauge wires.  See [https://www.youtube.com/watch?v=QzLvdR6X81k here]for how to attach the connectors to wires; you'll need a good [https://powerwerx.com/tricrimp-powerpole-connector-crimping-tool crimping tool] made for these connectors.  It's usually a good idea to use [https://powerwerx.com/powerpole-connector-retention-clip retention clips] to prevent connections from coming loose during competitions.
+ * For low current connections used to carry signals and data (but not to power heavy loads), thinner wires such as 22-26AWG is used; there are many connector choices, but connectors with a [https://www.allelectronics.com/item/con-340/3-conductor-locking-connectors-w/leads/1.html locking]feature are essential for robotics.  Without a locking feature, connections '''''will '''''work their way loose due to the vibration and impact involved in robotics competitions.  Many industries have developed appropriate connector solutions including the automotive and telecommunications industries.
+   * Telecommunications connections usually use the [https://en.wikipedia.org/wiki/Modular_connector modular plug] (e.g. for telephone and Ethernet) and flat wire (often called [https://www.monoprice.com/product?c_id=102&cp_id=10222&cs_id=1022205&p_id=952&seq=1&format=2 silver satin]).  These connectors are very inexpensive, lock securely, and are quick and easy to install.  They are available for 2, 4, 6, and 8 wires.  See [https://www.youtube.com/watch?v=k4aL62ixJVc here]for how to attach a modular plug.  Cable solutions can be made using inexpensive [https://www.newegg.com/Product/Product.aspx?Item=9SIA6705VG0350 extension connectors] or [https://www.showmecables.com/rj11-inline-coupler-straight F-F couplers] so that all wired connections use the easy-to-install male plugs.
+   * Automotive industries have a wide variety of connectors designed to be robust in high temperature, high vibration environments.  See 3-conductor, [https://www.allelectronics.com/item/con-440/4-conductor-locking-connectors-w/leads/1.html 4-conductor], other [https://www.allelectronics.com/item/con-104/4-conductor-multi-pin-connector-round-pins/1.html 4-conductor], [https://www.allelectronics.com/item/con-540/5-conductor-locking-connector-w/leads/1.html 5-conductor], etc. connectors
+ * [https://www.andersonpower.com/_global-assets/downloads/pdf/ds-sb50.pdf Anderson SB50A] connectors are used for the highest-current (up to 120A) connections (usually the battery) with 6-8 gauge wires.  See [https://www.youtube.com/watch?v=RQTjvsnyiDY here]for how to attach the connectors to wires.
+ * [https://www.andersonpower.com/us/en/products/powerpole/index.aspx Anderson Powerpole] PP15, PP30, PP45 connectors used for high-current (up to 15A, 30A, or 45A) connections (usually motors) with 10-12 gauge wires.  See [https://www.youtube.com/watch?v=QzLvdR6X81k here]for how to attach the connectors to wires; you'll need a good [https://powerwerx.com/tricrimp-powerpole-connector-crimping-tool crimping tool] made for these connectors.  It's usually a good idea to use [https://powerwerx.com/powerpole-connector-retention-clip retention clips] to prevent connections from coming loose during competitions.
+ * For low current connections used to carry signals and data (but not to power heavy loads), thinner wires such as 22-26AWG is used; there are many connector choices, but connectors with a [https://www.allelectronics.com/item/con-340/3-conductor-locking-connectors-w/leads/1.html locking]feature are essential for robotics.  Without a locking feature, connections '''''will '''''work their way loose due to the vibration and impact involved in robotics competitions.  Many industries have developed appropriate connector solutions including the automotive and telecommunications industries.
+   * Telecommunications connections usually use the [https://en.wikipedia.org/wiki/Modular_connector modular plug] (e.g. for telephone and Ethernet) and flat wire (often called [https://www.monoprice.com/product?c_id=102&cp_id=10222&cs_id=1022205&p_id=952&seq=1&format=2 silver satin]).  These connectors are very inexpensive, lock securely, and are quick and easy to install.  They are available for 2, 4, 6, and 8 wires.  See [https://www.youtube.com/watch?v=k4aL62ixJVc here]for how to attach a modular plug.  Cable solutions can be made using inexpensive [https://www.newegg.com/Product/Product.aspx?Item=9SIA6705VG0350 extension connectors] or [https://www.showmecables.com/rj11-inline-coupler-straight F-F couplers] so that all wired connections use the easy-to-install male plugs.
+   * Automotive industries have a wide variety of connectors designed to be robust in high temperature, high vibration environments.  See 3-conductor, [https://www.allelectronics.com/item/con-440/4-conductor-locking-connectors-w/leads/1.html 4-conductor], other [https://www.allelectronics.com/item/con-104/4-conductor-multi-pin-connector-round-pins/1.html 4-conductor], [https://www.allelectronics.com/item/con-540/5-conductor-locking-connector-w/leads/1.html 5-conductor], etc. connectors
+   * For wires that will not be stressed, [https://www.aliexpress.com/store/product/10x-2p-Spring-Connector-wire-with-no-welding-no-screws-Quick-Connector-cable-clamp-Terminal-Block/1612007_32321415301.html lever action] connectors that can be secured to the robot chassis offer another good choice.
 See [https://www.youtube.com/watch?v=UcOv1a2rK2g this video] for how to attach all sorts of commonly used FRC connectors.
 == Power Distribution ==
 [[Image(http://cdn3.volusion.com/vyfsn.knvgw/v/vspfiles/photos/am-2856-2.jpg?1442240393, 25%)]] Power from the battery goes through the master breaker and into a Power Distribution Panel (PDP).  The PDP distributes the battery power to the various circuits in the robot.  The PDP monitors the current flowing through it so the robot computer can monitor the current drawn by each circuit.
+[[Image(http://cdn3.volusion.com/vyfsn.knvgw/v/vspfiles/photos/am-2856-2.jpg?1442240393, 25%, right)]] Power from the battery goes through the master breaker and into a Power Distribution Panel (PDP).  The PDP distributes the battery power to the various circuits in the robot.  The PDP monitors the current flowing through it so the robot computer can monitor the current drawn by each circuit.
+Each circuit leading from the PDP to the robot loads should be provided with a [https://www.andymark.com/40-Amp-Snap-Action-Breaker-p/am-0288.htm snap breaker] that is  appropriately sized (5, 10, 20, 30, or 40A) for protecting the circuit it will be  powering.  For example, FRC rules specify that the smallest gauge (thinnest) wire you can use for powering motors is 12AWG which is limited to 41A so a 40A breaker might be used to protect it (you should also probably use thicker wire to provide some margin for error).  Snap breakers use two metals that bend at different rates when heated; the metals are arranged to touch securely and conduct electricity when cool, but when heated, will deform and snap apart, opening the circuit and protecting the wiring from overheating.
+Each circuit leading from the PDP to the robot loads should be provided with a [https://www.andymark.com/40-Amp-Snap-Action-Breaker-p/am-0288.htm snap breaker] that is  appropriately sized (5, 10, 20, 30, or 40A) for protecting the circuit it will be  powering.  For example, FRC rules specify that the smallest gauge (thinnest) wire you can use for powering motors is 12AWG which is limited to 41A so a 40A breaker might be used to protect it (you should also probably use thicker wire to provide some margin for error).  Snap breakers use two metals that bend at different rates when heated; the metals are arranged to touch securely and conduct electricity when cool, but when heated, will deform and snap apart, opening the circuit and protecting the wiring from overheating.
+The PDP uses two types of connectors:
+ * WAGO connectors for wiring to high current loads (motors)
+ * Weidmuller connectors for wiring low-current signals (e.g. to the roboRIO)
+Consult the [http://ctr-electronics.com/PDP%20User's%20Guide.pdf PDP user manual] for information on how to insert and remove wires from the connectors.
 == Voltage Regulation ==
 …
 == Motor Controllers ==
+[[Image(https://www.vexrobotics.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/2/1/217-4358-on-talon.jpg,25%,left)]] Motor controllers allow the robot computer to control the speed and direction of each motor.  There are several popular models including:
+ * [http://www.andymark.com/Talon-SRX-p/am-2854.htm Talon SRX]
+ * [https://www.andymark.com/Talon-p/am-talon-discontinued.htm Talon SR] (discontinued)
+ * [http://www.andymark.com/Victor-SP-p/am-2855.htm Victor SP]
+ * [http://www.revrobotics.com/spark/ Spark]
+The