# Commission Delegated Regulation (EU) 2015/68 of 15 October 2014 supplementing Regulation (EU) No 167/2013 of the European Parliament and of the Council with regard to vehicle braking requirements for the approval of agricultural and forestry vehicles (Text with EEA relevance), Division 2.2: Symbols valid for all types of brakes (see Figure 1 of Appendix 1)

Extent: E+W+S+N.I.

2.2.1. GA towed vehicle's technically permissible ‘maximum mass’ as declared by the manufacturer;
2.2.2. G′A towed vehicle's ‘maximum mass’ capable of being braked by the control device, as declared by the manufacturer;
2.2.3. GB towed vehicle's ‘maximum mass’ capable of being braked by joint operation of all of the towed vehicle's brakes
GB = n · GBo
2.2.4. GBo fraction of towed vehicle's permissible maximum mass capable of being braked by one brake, as declared by the manufacturer;
2.2.5. B* required braking force;
2.2.6. B required braking force taking account of rolling resistance;
2.2.7. D* permissible thrust on coupling;
2.2.8. D thrust on coupling;
2.2.9. P′ control device output force;
2.2.10. K supplementary force of control device, conventionally designated by the force D corresponding to the point of intersection with the axis of the abscissae of the extrapolated curve expressing P′ in terms of D, measured with the device in the mid-travel position (see Figures 2 and 3 of Appendix 1);
2.2.11. KA force threshold of control device, i.e., the maximum thrust on the coupling head which can be applied for a short period of time without generating an output force from the control device. The symbol KA is conventionally applied to the force measured when the coupling head begins to be pushed home at a speed of 10 to 15 mm/s, the control device transmission being uncoupled;
2.2.12. D1 the maximum force applied to the coupling head when it is being pushed home at a speed of s mm/s + 10 %, the transmission being uncoupled;
2.2.13. D2 the maximum force applied to the coupling head when it is being pulled at a speed of s mm/s + 10 % out of the position of maximum compression, the transmission being uncoupled;
2.2.14. ηHo efficiency of inertia control device;
2.2.15. ηH1 efficiency of transmission system;
2.2.16. ηH overall efficiency of control device and transmission ηH = ηHo · ηH1;
2.2.17. s travel of control device in millimetres;
2.2.18. s′ effective (useful) travel of control device in millimetres, determined as required by point 10.4;
2.2.19. s″ spare travel of master cylinder, measured in millimetres at coupling head;
2.2.19.1. sHz stroke of the master cylinder in millimetres according to Figure 8 of Appendix 1;
2.2.19.2. s″Hz spare travel of the master cylinder in millimetres at piston rod, according to Figure 8 of Appendix 1;
2.2.20. so loss of travel, i.e., travel in millimetres of the coupling head when the latter is so actuated as to move from 300 mm above to 300 mm below the horizontal, the transmission remaining stationary;
2.2.21. 2sB brake-shoe lift (brake-shoe application travel), in millimetres, measured on diameter parallel to applying device, the brakes not being adjusted during the test;
2.2.22. 2sB* minimum brake shoe centre lift (minimum brake shoe application travel) (in millimetres) for wheel brakes with drum brakes
2s B * = 2,4 + 4 1000 × 2r ;
2r being the diameter of the brake drum in millimetres (see Figure 4 of Appendix 1).
2s B * = 1,1 × 10 × V 60 F RZ + 1 1000 × 2 ra For wheel brakes with disc brakes with hydraulic transmission
Where:
V60 fluid volume absorbed by one wheel brake at a pressure corresponding to a braking force of 1,2 B* = 0,6 · GBo and a maximum tyre radius;
and
2rA outer diameter of brake disc (V60 in cm3, FRZ in cm2 and rA in mm).
2.2.23. M* braking torque as specified by the manufacturer. This braking torque shall produce at least the prescribed braking force B*;
2.2.23.1. MT test braking torque in the case where no overload protector is fitted (according to point 6.2.1);
2.2.24. R dynamic tyre rolling radius. As an alternative for vehicles of categories Ra and Sa, the static loaded radius, as specified by the tyre manufacturer, may be used instead of the dynamic tyre rolling radius;
2.2.25. n number of brakes.
2.2.26. Mr maximum braking torque resulting from the maximum permissible travel sr or the maximum permissible fluid volume Vr when the towed vehicle moves rearward (including rolling resistance = 0,01 · g · GBo);
2.2.27. sr maximum permissible travel at the brake control lever when the towed vehicle moves rearward;
2.2.28. Vr maximum permissible fluid volume absorbed by one braking wheel when the towed vehicle moves rearward;

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Source: https://www.legislation.gov.uk/eur/2015/68/annex/VIII/division/2/division/2.2 (the official version)
Page: https://openlegislation.uk/eu-regulation-2015-68/annex-VIII/division-2/division-2.2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.