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Foreword
The Philippine National Standard (PNS) for Agricultural Machinery – Four-Wheel
Tractors – Specifications (PNS/BAFS PABES 301:2020) was developed by the
Bureau of Agriculture and Fisheries Standards (BAFS) as per the request of Task-
Force PAES of the Philippine Council for Agriculture and Fisheries (PCAF). It has been
prepared by the Technical Working Group (TWG) for the revision of PAES for Four-
Wheel Tractors and Walking Type Agricultural Tractors per approved Department of
Agriculture Special Order No. 290 series of 2017.
In the development of the Standard, some provisions were adopted from the following
documents:
ISO 6489-3: 2004, Agricultural Vehicles – Mechanical connections between
towed and towing vehicles – Part 3: Tractor Drawbar
ISO 500-1:2014, Agricultural Tractors – Rear-mounted power take-off types
1,2,3,4 – Part 1: General specifications, safety requirements, dimensions for
master shield and clearance zone
ISO 730:2009, Agricultural Wheeled Tractors- Rear-mounted three-point
linkage – Categories 1N, 1, 2N, 2, 3N, 3, 4N and 4; and
IRRI Rice Production Manual.
This Standard includes the following significant changes compared to the previous
edition:
Deletion of the second paragraph in Clause 1- Scope
Revision of the definition of the term “drawbar”
Inclusion of the term “rated power” in Clause 3
Revision of the definition for “roll- over protective structure”
Adoption of the terms and definitions related to dimensions and components of
three-point linkage from ISO reference
Deletion of “lower hitch point tire clearance” and “lower hitch point tractor
clearance” in Clause 3
Revision of the definition for “linchpin”
Deletion of “four-wheel drive” and “two-wheel drive” in Clause 3
Inclusion of the discussions for “two- wheel drive” and “four-wheel drive” in
Clause 4
Modification of Figures for “four-wheel drive” and “two-wheel drive”
Inclusion of classification based on transmission system
Revision on the title of Clause 5 to “Four-wheel Tractor Parts and
Components” and the provisions under it
Deletion of provision for materials in Clause 5
Revisions on the provisions under Clause 5.2 – Controls
Revision of provisions for three-point linkage categories and its dimensions
based on updated ISO references
Inclusion of provision for dimensions and components of three-point linkage in
Clause 5.3
Modification of figure for “Clevis- type drawbar hole diameter, thickness, and
width”
Deletion of provision for transmission systems in Clause 5
Revisions on the provisions for PTO shaft in Clause 5
Addition of pneumatic brake/ air brake as a manner of transmitting the force
from the control for brake system in Clause 5
Deletion of the provision for allowable wheel slip for maximum efficiency in
Clause 6
Addition of minimum PTO power and maximum specific fuel consumption as
part of the performance requirements in Clause 6
