ISO 4414:2010 pdf free download – Pneumatic fluid power一General rules and safety requirements for systems and their components.
5.4.6.4 Stability
Pressure and flow control valves shall be selected so that changes in actual pressure, actual temperature or
load do not cause a malfunction or a hazard.
5.4.6.5 Tamper resistance
Pressure and flow control valves or their enclosures shall be fitted with tamper-resistant devices (e.g. key lock on a pressure regulator) where an unauthorized alteration to pressure or flow can cause a hazard or malfunction,
5.4.6.6 Manual control levers
The direction of movement of manually operated levers shall not be confusing: for example, moving a lever up
should not lower the controlled device; see IEC 61310-3.
5.4.6.7 Manual set-up controls
If manual control is provided for setting up, this control shall be safely designed and have priority over automatic controls in the set-up mode.
5.4.6.8 Two-hand controls
If two-hand controls are provided, they shall be designed and applied in accordance with ISO 13851.
5.4.6.9 Safe position
Any actuator required to maintain its position or to adopt a specific position for safety in the event of a control system failure shall be controlled by a valve that is held in or switched back to the safe position (e.g. by spring tension or comparable physical principle).
NOTE To leave the safe position, pressure or force is necessary; see ISO 13849-2:2003, Table B.2.
5.4.6.10 Control systems with servo or proportional valves
5.4.6.10.1 Override systems
Where actuators are controlled by servo or proportional valves and malfunction of the control system can result in the actuators causing a hazard, means shall be provided to maintain or recover control, or stop the motion, of these actuators.
5.4.6.10.2 Additional devices
Actuators whose speed is controlled by servo or proportional valves shall have means to hold or move the
actuator to a safe position if unintended movement may cause a hazard.
5.4.6.11 Monitoring of system parameters
Where changes in the system operating parameters can constitute a hazard, clear indication of the system operating parameters. e.g. temperature, pressure, shall be provided.
5.4.6.12 Control of multiple devices
Where there is more than one interrelated automatically and/or manually controlled device on the machine. and where failure of any of these devices can cause a hazard, protective interlocks or other safety means shall be provided. Where practicable, these interlocks should interrupt all operations, provided that such interruption does not of itself cause a hazard.
5.4.6.13 Control of sequencing by position sensing
Sequencing by position sensing shall be used wherever practicable and shall always be used when a
sequencing malfunction of a pressure or a time-lapse control, on its own, can cause a hazard or damage.
5.4.6.14 Location of controls
5.4.6.14.1 Manual controls
The location and mounting of manual controls shall
a) place the control within reach of the operator’s normal working position:
b) not require the operator to reach past rotating or moving devices to operate the control:
C) not interfere with the operator’s required working movements;
d) be designed, selected and located so that an operator is not exposed to hazards.
5.4.6.14.2 Enclosures and compartments
The size of enclosures, compartments, doors and covers and the arrangement of the control devices within
shall provide adequate room for maintenance and ventilation.
5.4.6.15 Emergency controls
The system shall incorporate an emergency stop in accordance with Iso 13850, or emergency control.
5.4.7 Diagnostics and monitoring
5.4.7.1 Pressure measurement
5.4.7.1.1 Pressure-measuring instruments should be selected with a pressure-measuring range such that the maximum working pressure of the system does not exceed 75 % of the maximum scale value for steadystate pressure or 65 % of the maximum scale value for cyclic pressure.
5.4.7.1.2 Where pressure-measuring instruments are included as permanent items in a system, they shall be protected from rapidly fluctuating pressure.
5.4.7.2 Electrical supply indicators
Electrical devices should be incorporated to indicate the state of the electrical signal to individual components.