# 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 2.3: Symbols valid for mechanical-transmission braking systems (see Figure 5 of Appendix 1 )

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

2.3.1. iHo reduction ratio between travel of coupling head and travel of lever at output side of control device;
2.3.2. iH1 reduction ratio between travel of lever at output side of control device and travel of brake lever (gearing down of transmission);
2.3.3. iH reduction ratio between travel of coupling head and travel of brake lever
iH = iHo · iH1
2.3.4. ig reduction ratio between travel of brake lever and lift (application travel) at brake-shoe centre (see Figure 4 of Appendix 1);
2.3.5. P force applied to the brake control lever; (see Figure 4 of Appendix 1);
2.3.6. Po brake-retraction force when the towed vehicle moves forward, i.e., in graph M = f(P), the value of the force P at the point of intersection of the extrapolation of this function with the abscissa (see Figure 6 of Appendix 1);
2.3.6.1. Por brake-retraction force when the towed vehicle moves rearward (see Figure 6 of Appendix 1);
2.3.7. P* force applied to the brake control lever to produce the braking force B*;
2.3.8. PT test force according to point 6.2.1;
2.3.9. ρ characteristic of the brake when the towed vehicle moves forward as defined from:
M = ρ (P – Po)
2.3.9.1. ρr characteristic of the brake when the towed vehicle moves rearward as defined from:
Mr = ρr (Pr – Por)
2.3.10. scf rear cable or rod travel at compensator when brakes operate in forward direction;
2.3.11. scr rear cable or rod travel at compensator when brakes operate in rearward direction;
2.3.12. scd differential travel at compensator when only one brake operates in the forward direction and the other in the reverse direction;
Where: scd = scr – scf (see Figure 5A of Appendix 1);

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Source: https://www.legislation.gov.uk/eur/2015/68/annex/VIII/division/2/division/2.3 (the official version)
Page: https://openlegislation.uk/eu-regulation-2015-68/annex-VIII/division-2/division-2.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.