Critical Technical Advantages
High Dynamic Response: The 3620JP is engineered to provide accurate and rapid valve positioning. It features an easily adjustable minor loop gain, allowing technicians to fine-tune the positioner to optimize the dynamic response for specific actuator sizes and varying application requirements.
Environmental Resilience: Built for the “real world,” the case, internal components, and gasket materials are designed to withstand harsh chemical and weather conditions. Additionally, the positioner utilizes “bleed air” to internally purge its own housing and the actuator housing, providing a constant positive pressure that prevents the ingress of corrosive contaminants.
Simplified Maintenance and Calibration: With the cover removed, all critical calibration points—including zero, span, and cross-over adjustments—are easily accessible. These adjustments can be performed with a standard screwdriver, simplifying field service.
Part Interchangeability: Most components within the 3620JP series are interchangeable. This design philosophy was intended to reduce the inventory burden on plants by requiring fewer unique spare parts to support a large fleet of positioners.
Supply Pressure Stability: The positioner is designed to be insensitive to fluctuations in the plant air supply. Changes in supply pressure have a minimal effect on operation, ensuring consistent valve control even when the air header pressure varies.
Field-Reversible Action: Switching between direct and reverse action is achieved through simple adjustments. No additional parts or conversion kits are required to change the positioner’s response to the input signal.
Technical Performance Matrix
| Feature | Details |
| Type | Electro-Pneumatic (I/P) Positioner |
| Status | Obsolete (Legacy Support Only) |
| Input Signal | 4-20 mA DC (Typical) |
| Adjustments | Zero, Span, Cross-over, and Minor Loop Gain |
| Protection | Internal Air Purge System |
| Calibration | Manual (Screwdriver accessible) |
Primary Applications
Double-Acting Actuators: Specifically optimized for the control requirements of double-acting pneumatic pistons and cylinders.
High-Vibration Service: Maintaining loop stability on valves located near compressors, pumps, or high-turbulence flow areas.
Corrosive Environments: Utilizing the internal purge feature to survive in coastal or chemical-heavy atmospheres.
Legacy System Support: Maintaining existing plant infrastructure where 3620JP units are already integrated into the control logic.
