Overview
ISO 20401:2017 specifies standardized pin assignment for electrical round connectors used on pneumatic directional control valves. It applies to 8 mm and 12 mm diameter round plug connectors as defined in IEC 60947-5-2 (Figures D.2 and D.4). The standard ensures consistent wiring and electrical interface for solenoid-actuated valves in pneumatic fluid power systems, supporting interoperability, safe installation, and simplified maintenance.
Key Topics and Requirements
- Scope: Pin assignment for directional control valves used with 8 mm and 12 mm electrical round connectors according to IEC 60947-5-2.
- Connector types: Definitions refer specifically to the connector forms shown in IEC 60947-5-2 (male face views for 12 mm five-pin and 8 mm four-pin connectors).
- Pin allocation (explicit):
- Valves with a single solenoid:
- Pin 1: not used
- Pin 2: not used
- Pin 3: 0 V (solenoid)
- Pin 4: UB (supply voltage for solenoid)
- Valves with double solenoids (one connector):
- Pin 1: not used
- Pin 2: UB for solenoid 12
- Pin 3: 0 V for solenoids
- Pin 4: UB for solenoid 14
- Valves with double solenoids (two connectors):
- For both connectors:
- Pin 1: not used
- Pin 2: not used
- Pin 3: 0 V
- Pin 4: UB
- Identification & symbols:
- Port and control mechanism identification follows ISO 11727.
- Graphical symbols used are in accordance with ISO 1219-1.
- Normative references: ISO 5598 (vocabulary), IEC 60947-5-2 (proximity switch connectors), plus related ISO documents.
Applications and Who Uses It
- Pneumatic valve manufacturers: implement standardized pinouts to ensure product compatibility.
- OEMs and machine builders: design machines with consistent electrical interfaces for directional control valves.
- System integrators and panel builders: reduce wiring errors and commissioning time through predictable connector pinning.
- Maintenance and service engineers: quickly diagnose and replace solenoid valves without consulting device-specific wiring diagrams.
- Safety and compliance teams: use the standard to demonstrate conformity with international switchgear and control interface practices.
Related Standards
Keywords: ISO 20401:2017, pneumatic fluid power, directional control valves, pin assignment, 8 mm connector, 12 mm connector, IEC 60947-5-2, solenoid pin allocation.