Equipment Standards

     A. Motive Power

     B. Rolling Stock

     C. Consists/Unit Trains

     D. Load requirements

     E. Couplers

     F. Trucks and Wheelsets

     G. Rolling Resistance

     H. Weight

     I. Appearance

     J. Detection Requirements

     K. DCC Rules

     L. Lighting



A. Motive Power


  1. Powered and non-powered (dummy) locomotive sets with their associated equipment, such as tenders, are to have insulated couplers and draft gear on the rear end of the set and on the front end when practical. Non-standard couplers and or drawbars may be used for Internal coupling of locomotive sets.
  2. Locomotives to be lead qualified must have a working headlight.
  3. Special lighting (mars, strobe lights, marker lights, number boards, step lights etc.) is encouraged.
  4. Locomotives are to have their owner's membership identification name or number on the underside.
  5. Responsibility for maintenance and repair is the owner.

B. Rolling Stock


  1. The owner is responsible for maintenance and repair. The Car Dept with car owners permission, will make certain "running repairs" as time, manpower and supplies allow. The running repairs are defined as coupler height adjustment, centering spring and knuckle spring replacements and wheel cleaning.
  2. New or repaired cars are to be inspected by the Car Inspector prior to operation on the layout.
  3. Cars bad ordered during an operating session shall not be returned to service without permission of the member in charge, or after successful reinspection.
  4. Cars and Locomotives are to have owner identification name or number displayed on the underside. Equipment left on the layout without identifying markings become the property of the San Diego Model Railroad Association.
  5. All cars shall have insulated couplers, draft gear, and trucks, except when electrical pickup is needed.

C. Consists/Unit Trains


  1. Locomotives and caboose must be the same or affiliate road names. Pool power from leasing companies and FREDs are allowed if prototypical.
  2. All cars within a consist shall be the same era. (i.e. 1930 ice bunker reefers vs. modern stack trains)
  3. Unit trains may be granted a variance from certain standards by the Car Inspector at the request of the owner.

D. Load requirements


  1. Loose loads are not permitted on cars at any time.
  2. Loads may not be used to meet minimum car weight requirements unless permanently attached to the car.
  3. Loads on flat cars, log cars, etc. must be secured with scale chain, rope, cable, or banding.
  4. Loads must not interfere with running characteristics, clearances, or other car properties.

E. Couplers


  1. The Kadee delayed action magnetic coupler is the Association Standard coupler. Use of other couplers is permitted (e.g. McHenry) provided reliable operation is guaranteed. Non-knuckle couplers may be granted a variance if not prototypical for a model.
  2. Couplers shall be maintained at the correct height from the rail as measured by the height gauge maintained by the Car Inspector. (NOTE : This gauge conforms to the Kadee # 205 Multipurpose Coupler Height Gauge.).
  3. Dummy (non-operating) couplers are allowed only on locomotives and rolling stock that is intended to run as a set as in unit and passenger trains. The external couplers are to be fully functional and equipped with glad hands.
  4. Working couplers on both ends of equipment are not required when deemed not practical.
  5. Truck mounted couplers are not acceptable, except as used on prototype equipment.

F. Trucks and Wheelsets


  1. Wheelsets shall conform to the NMRA MARK II Standards gauge (RP-25). Metal wheels are not required at this time, but are strongly encourged.
  2. All axles are to be non-magnetic to avoid difficulties with uncoupling ramps except when an axle is needed for electrical purposes.
  3. Brake shoes on trucks shall not interfere with wheel rotation.
  4. Trucks must not be so tight as to cause derailments, nor so loose as to produce excessive car wobble.

G. Rolling Resistance


  1. All cars (except those equipped for electrical pickup) placed on the layout for operations shall start rolling on their own on a 3% grade.
  2. Cars should not start rolling on a .1% grade.
  3. Any car not meeting the above rolling resistance requirement may be operated as part of a unit train and will be excluded from switching operations.

H. Weight


  1. All cars and dummy (non-powered) locomotives shall be weighted according to the Association HO car inspection charts. (The charts are based on the NMRA Recommended Practice - RP20.1.) EXCEPTION: Open log cars, cabooses, transient, and special equipment may be granted a variance by the car inspector or member in charge.
  2. Double stack and container/TOFC cars and similar must meet weight requirements when empty, if loads are removable.
  3. The Association-owned digital scale shall be used to validate car weight.
  4. At the judicious discretion of the Car inspector, certain cars may be exempt from the maximum weight requirement.

I. Appearance


  1. Cars operated on the layout while open for the public shall not be "toy like" in appearance. Toy like assessments made by the Car Inspector, may be appealed to the Vice President/General Manager.
  2. Car weights are not to be visible in normal operation.
  3. Ice-bunker reefers are to have hatch covers and boxcars are to have doors. Boxcars that are in veneer service may be used without doors.
  4. Damaged cars that reveal raw plastic, wood or metal are not to be operated on layout.
  5. Weathering is strongly encouraged but reporting marks must be readable if the car is to be registered.
  6. Undecorated equipment (cars and locomotives lacking finish paint or numbers) and unfinished equipment (cars and locomotives lacking  significant parts) are not used during normal operating hours without the express permission of the member in charge or Association officer.

J. Detection Requirements


  1. The ends of all trains must be detectable by the layout electrical block occupancy system.
  2. For most powered locomotives and self-propelled cars, the motor will provide sufficient resistance.
  3. A resistance of 5,000 to 10,000 OHMS (10,000 preferred) across the rails is required via a pickup wheelset to activate the layout electrical block occupancy system. The use of a lamp or LEDs may be used for illumination, but the use of a lamp or LED does not satisfy the requirement for resistance across a wheel set, owing to the possibility of lamp/LED burnout. It is recommended that there be one resistor per car.

K. DCC Decoder Rules


  1. DCC decoders shall use long addresses unless approved by the operator-in-charge.
  2. Use of the default address (short address "3") is not permitted during operations.
  3. Consist numbers shall be coordinated with the operator-in-charge. Consists may not be killed except by the owner of the equipment.
  4. ALL programming must be performed on the programming track. Exceptions are changing long addresses and setting up consists. No CV programming may be done on the main.

L. Lighting


  1. For maximum impact during night operations lighting systems installed in cabooses, passenger and camp cars is strongly encouraged. The lighting system used can be either track or battery powered and is subject to resistance requirements discussed above.
  2. End of Train devices (EOT) or FREDs are recommend for use on freight trains that are running without a caboose. Power may be supplied either from battery or track and is subject to the resistance requirements discussed above.
  3. Refer to Motive Power (paragraph A above) on locomotive lighting.



References


NMRA Standards - Standards and Recommended Practices
NMRA Standards - Wheels S-4
NMRA Recommended Practices - Standards Gauge RP-2
NMRA Recommended Practices - Car Weight - RP20.1
NMRA Recommended Practices - Coupler Contour RP 21.1
NMRA Recommended Practices - Coupler Pocket RP 22
NMRA Recommended Practices - Bolsters RP-23
NMRA Recommended Practices - Trucks RP-24
NMRA Recommended Practices Standards - Journals RP-24.1
NMRA Recommended Practices Standards - Wheel Sets RP-24.2
NMRA Recommended Practices Standards - Axles RP-24.3
NMRA Recommended Practices Standards - Wheel Contour RP-25
Kadee Conversion Charts
Kadee Coupler List
Kadee HO Trucks and Wheelsets



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