Railway Track Scales for In-Motion Weighing Specifications (SI/91-21)
Regulations are current to 2023-03-20
Railway Track Scales for In-Motion Weighing Specifications
Specifications Relating to the Design, Composition, Construction and Performance of Electronic Railway Track Scales for In-Motion Weighing and Relating to the Installation and Use Thereof
The Minister of Consumer and Corporate Affairs, pursuant to paragraph 10(1)(i) of the Weights and Measures Act and sections 13Footnote * and 27Footnote * of the Weights and Measures Regulations, C.R.C., c. 1605, hereby establishes the annexed Specifications relating to the design, composition, construction and performance of electronic railway track scales for in-motion weighing and relating to the installation and use thereof.
January 28, 1991
Return to footnote *SOR/78-792, 1978 Canada Gazette Part II, p. 3894
1 These Specifications may be cited as the Railway Track Scales for In-Motion Weighing Specifications.
2 (1) In these Specifications,
Act means the Weights and Measures Act; (Loi)
- actual tare
actual tare means the actual weight of an empty railway car determined by in-motion weighing; (tare réelle)
- double weighing
double weighing means the weighing of a railway car in two phases on the same track scale the results of which are automatically added together to register the whole weight of the railway car; (pesage en deux temps)
- dynamic adjustment
dynamic adjustment means an adjustment to electronic circuits of a track scale that is made to compensate for the effects of dynamic forces that affect the in-motion weighing of a railway car; (réglage dynamique)
- in-motion weighing
in-motion weighing or weighing means the weighing of railway cars while they are moving over the load-receiving element of a track scale; (pesage en mouvement or pesage)
registration means a displayed or printed value; (indication)
rollback means a reversal in direction of a railway car during the weighing process; (inversion de marche)
- single weighing
single weighing means the weighing of a railway car while it is entirely supported by a track scale; (pesage en un temps)
- stencilled tare
stencilled tare means the empty weight of a railway car as marked on the railway car; (tare inscrite au pochoir)
- track scale
track scale means an electronic weighing machine intended for use in trade for in-motion weighing of railway cars; (pont-bascule)
- wheel detector
wheel detector means a detection apparatus in the vicinity of a track scale, whether mounted or not on the track and including a photoelectric cell, that reacts to the motion of a railway car in order to control and monitor the sequence in the weighing process. (détecteur de roues)
(2) All other words and expressions used in these Specifications have the same meaning as in Part V of the Weights and Measures Regulations.
3 These Specifications apply to every electronic track scale intended for use in trade for the in-motion weighing of railway cars.
Design, Composition and Construction
4 (1) A track scale shall be provided with wheel detectors that
(a) initiate any logic sequence required to determine train velocity and axle configuration of railway cars and any other monitoring required for in-motion weighing; and
(b) permit the detection of any false logic or other malfunction that interferes with the proper operation of the track scale.
(2) Where any false logic or other malfunction is detected, the track scale shall become inoperable.
5 A track scale shall be designed to have a static operating mode and a dynamic operating mode and to indicate the operating mode selected.
6 A track scale shall be designed so that dynamic adjustment of a weight does not affect any adjustment in the static operating mode.
7 A track scale shall be designed so that the means provided to make coarse zero and span adjustments in the static and dynamic modes are sealable.
8 The means that is provided for dynamic adjustment in a track scale shall have a maximum range not exceeding 0.25 per cent of the capacity of the track scale.
9 A track scale shall be designed so that while operating in the static mode it provides weight registrations with a minimum increment of 10 kg or less.
10 Where a track scale is being used in a manner other than in the manner authorized by the approval issued pursuant to section 3 of the Act or by the certificate issued pursuant to section 19 of the Act, the registration of the track scale shall be accompanied by a statement indicating that the registration shall not be used in trade.
11 Where a track scale incorporates a printer,
(a) means shall be provided to prevent a keyboard entry from altering data that has been entered or is being entered in respect of the in-motion weighing of a railway car;
(b) every keyboard entry of weight data shall be accompanied by a statement indicating that it is a keyboard entry;
(c) the printer shall indicate the operating mode of the track scale when used for any purpose other than in-motion weighing;
(d) the printer shall provide a printed record that
(i) includes the date and time of entry,
(ii) the identification number and weight of each railway car, and
(iii) subject to subsection 12(1), the total gross weight of the railway cars where summation of net weights is required;
(e) means shall be provided to prevent printing of the weight of the locomotive;
(f) means shall be provided so that on completion of the in-motion weighing of a railway car and the printing of the weight of the railway car, all stored weight data in respect of that railway car is automatically cleared; and
(g) the weight corresponding to the tare of a railway car shall be accompanied by the words “actual tare” or “tare réelle”, or the words “stencilled tare” or “tare inscrite au pochoir”, as the case may be, where that weight is printed on a record.
Track Scales for Unit Trains
12 (1) A track scale intended to be used solely for the in-motion weighing of unit trains shall not compute or register the net weight of individual railway cars.
(2) The gross weight of individual railway cars in a unit train may be printed for the purpose of determining overload if each printed weight is accompanied by the letters “UT” or “TB”.
13 A track scale shall be designed to prevent registration of the weight of a railway car while the car is moving at a velocity greater than the maximum operating velocity for which the track scale is approved pursuant to section 3 of the Act.
14 A track scale shall be designed so that, where the velocity of the railway car exceeds the maximum limit specified in the notice of approval issued in respect of the track scale pursuant to section 3 of the Act, the track scale
(a) prevents the weight of the railway car from being printed or stored in the track scale memory; and
(b) locates and identifies the railway car and gives an audible or other signal to alert the operator.
15 The rails of the weighbridge in a track scale shall be fastened securely to prevent any unusual movement of the rails on the application of a load.
16 Each end support of a weighbridge shall be positioned so as to prevent any lifting of the weighbridge on the application of a load to any part of the weighbridge.
17 Movement of the weighbridge shall be constrained both longitudinally and transversely to the extent necessary to ensure proper operation of the track scale.
18 A track scale shall be designed so that after the application of power, the registering of weight data is delayed until the manufacturer’s recommended warm-up time has elapsed.
Prevention of Registration
19 A track scale designed so that weighing requires that the operator activate particular controls or automatic sequencing shall be provided with means to prevent the track scale registering any weight until the activation of the controls or automatic sequencing is completed.
20 A track scale shall stop registering weights when a rollback of railway cars occurs unless the track scale is designed for in-motion weighing of railway cars while rollback occurs.
Automatic Track Scale
21 An automatic track scale shall be provided with means to prevent the registering of weight until the scale has been reset to zero at the beginning of a weighing sequence.
Installation and Use
Approach and Departure Rails
22 The foundations and anchoring of the approach and departure rails shall be of sufficient strength and rigidity to ensure that
(a) the approach and departure rails remain parallel and in alignment horizontally and vertically with the rails of the weighbridge; and
(b) thermal expansion and contraction does not adversely affect the proper operation of the track scale.
23 (1) For double weighing of coupled railway cars, the approach and departure rails shall be straight, uninterrupted and without joints for a distance of not less than 30 m.
(2) For double weighing of uncoupled railway cars, the approach and departure rails shall be straight, uninterrupted and without joints for a distance of not less than 25 m.
(3) For single weighing of railway cars, the approach rails shall be straight for a distance of not less than 25 m.
24 Every gap between the weighbridge rails and the approach and departure rails shall be minimized by means of transverse bevelling and overlapping of the rails or by any other similar means that reduces the impact at the gap.
25 The stencilled tare of a railway car shall be used only for the purpose of determining transportation charges for goods and only if the following conditions are met:
(a) the stencilled tare weight shall be marked in 50 kg increments or less and shall be accompanied by the date on which the stencilled tare weight was determined; and
(b) the difference between the actual tare and the stencilled tare shall not exceed
(i) 150 kg, for a railway car of 25 000 kg or less,
(ii) 200 kg for a railway car of more than 25 000 kg but not more than 30 000 kg, and
(iii) 250 kg for a railway car of more than 30 000 kg.
26 Where actual tare is used and stored in the track scale memory following in-motion weighing of an empty railway car, the actual tare shall be accompanied by a railway car identification code.
27 (1) For weight assessment of commodities, other than to determine transportation charges, a train shall be weighed loaded and unloaded, and the difference between the two weights shall represent the net weight of the quantity of commodities in the unit train or each individual railway car, as applicable.
(2) The weights referred to in subsection (1) shall be erased from the track scale memory immediately after the printing of the net weight of the quantity of commodities.
28 If the net weight of individual railway cars is determined, the gross weight, the tare and the net weight of each individual railway car shall be registered with the indication “gross weight” or “poids brut”, “tare”, or “net weight” or “poids net”, as appropriate, and where the information is stored in the track scale memory it shall be automatically cleared immediately after printing.
29 Where the registration of the weight of a railway car is prevented for any reason, the railway car shall be re-weighed if the weight is being used in trade.
30 All interconnecting wiring between the load cells, the junction boxes and the instrumentation that forms part of a track scale shall be shielded and grounded and enclosed in conduits.
31 Load cell cables shall be separated from power cables and shall not be run in the same conduit.
32 Shims or other height or level adjustment features of a permanent track scale shall be clean, smooth and made of steel or any other material of equivalent strength and, if not grouted, shall cover sufficient area under level stands or load cell bases to ensure maintenance of a stable and level condition under normal conditions of use.
33 The operating velocity limits specified in the notice of approval issued in respect of a track scale pursuant to section 3 of the Act shall be prominently displayed near the means of registration of the track scale.
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