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Field Inspection Manual — Non-Automatic Weighing Devices

Part 2, Section 12: IPO-12: Railway Track Scales


Mechanical or electronic railway track scales, and combination railway track/vehicle scales


Inspector's weight kit, at least one certified railway test car, local standards and suitable strain loads.

Note: When performing an initial inspection, refer to the Bulletin M-5 for the minimum amount of standards.


Device is approved for trade use (NoA, Act Section 8)

Device is suitable for the actual use (STP-1)

Device has been initially inspected (if applicable) and bears the initial verification marks (R.29)

Device is sealed (NoA, STP-4)

Visual Examination — Installation and Location (STP-7)

Device is installed in accordance with restrictions and conditions listed in the notice of approval and in accordance with manufacturer's instructions

Device is permanently installed on adequate foundations

Installation provide access to understructure of main elements (pit entrance)

Adequate approach and departure ends

Local standards and test equipment can be brought to the device and used for inspection

Device indicating and load receiving elements are positioned for customer's view (if applicable)

Load receiving element can be observed from indicator's reading position

Clearance around load receptor

Installation of load cells, levers are adequate

Device is adequately protected

Visual Examination — Marking (STP-3)

Device is marked with the required information

Marking is located as required

Marking is permanent (if applicable)

Marking plate is permanently attached to the device

Visual Examination — Indicating element (STP-5)


Display Test (Segment)

Indicated and recorded values are adequately defined

Defining words and symbols for annunciators (Tare Entered, Gross and Net Weight, Center-of-Zero) are readable


Scale marks, pointers and poise are in good condition

Defining words and symbols are readable

Zero setting material is enclosed and secured

Balancing ball is in good condition and secured in place

Visual Examination — Recording Element (Printer) (STP-6)

Device prints the required values

Printed values are adequately defined

Device Configuration (Electronic)

Device configured as prescribed by the NOA (STP-2)

Zero Setting Mechanism Range ( 4% of Max or more) (STP-8)

Initial Zero Setting Mechanism Range (20% of Max or more) Footnote 1

AZTM Maximum Range (0.6 e)

Manual Entries of Gross Weights (STP-9) Footnote 1

Sleep Mode Test (STP-10) Footnote 1

Tare (Platter, Keyboard, and Pre-programmed Tare Entry) (STP-11)

Free Floating Weight Signal (STP-12)


Load Discrimination Test (Near Zero) (STP-14)

Increasing Test (Strain Test) (STP-13)

Eccentricity Test (STP-15)

Load Discrimination (Max) (STP-14)

Agreement of Registration (STP-17)

Display Blanking Tests (Zero, Tare) (STP-18)

Decreasing and Return-to-Zero Test (STP-13)

Repeatability Test (STP-16)

Motion Detection Test (STP-19)

Mathematical Concordance of Tare, Net and Gross Weight (STP-21)

Disturbance Test (Electromagnetic Interference and Radio Frequency Interference, Vibrations). (STP-23)

Weigh-in/Weigh-out Systems (STP-24)

Weighing Systems with Multiple Weighing Elements (STP-26)


Original document


Footnote 1

Test performed at the initial inspection only.

Return to footnote 1 referrer

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