FOXBORO SRI986-CIDS7EAANA-C | Pneumatic Valve Positioner In Stock

Description

Key Technical Specifications

Product Introduction

Control valves in chemical plants and refineries are constantly fighting against pipe vibration, extreme temperature swings, and explosive atmospheres. The FOXBORO SRI986-CIDS7EAANA-C was engineered to sit right in the middle of that chaos and keep the valve exactly where it needs to be. As an intrinsically safe electro-pneumatic positioner, it takes your standard 4-20mA analog signal and converts it into precise pneumatic actuation without risking a spark in a Class I Div 1 environment.Field engineers actually trust this specific SRI986 revision because of its mechanical simplicity and ruggedness. Instead of relying on fragile digital menus that require proprietary laptops in the rain, this unit allows you to calibrate the zero point and stroke range independently using just two adjustment screws. It handles supply pressures up to 6 Bar and supports up to three-way split ranging, making it incredibly versatile for complex process loops. Just be aware that the two-screw calibration requires a steady hand and a good multimeter; it’s old-school, but it never crashes.

Quality SOP & Tech Pitfalls (The Reality Check)

The Lab Report (SOP):
We don’t just wipe the dust off and ship it. Every SRI986 positioner goes through a strict bench test. First, a visual and counterfeit check to ensure the nameplate and casting are genuine ECKARDT. Second, a live pneumatic test where we apply a 4-20mA ramp signal and verify the output pressure matches the valve stroke linearly. Third, we check the IP65 gasket integrity and seal the unit in anti-static packaging.The Engineer’s Warning (Pitfalls):
The most common mistake I see with the SRI986 is rushing the mechanical calibration. Because the zero and span adjustments are independent but interact slightly, you have to bounce back and forth between them to get it perfectly dialed in. I once watched a junior tech spend three hours chasing a hunting valve because he set the zero at 4mA and then adjusted the span, which shifted the zero back to 4.2mA. Always use a calibrated pressure gauge on the actuator and a precision mA source. Don’t trust the DCS readback for local calibration.

Installation & Configuration Guide

1. Pre-Installation: ⚠️ SAFETY FIRST. Isolate the air supply and lock out/tag out the electrical signal. Vent all residual pneumatic pressure. Take photos of the existing air tubing routing and feedback lever linkage.
2. Removal: Label the air supply, output, and vent lines. Unbolt the mounting bracket. Carefully disconnect the feedback linkage to avoid bending the cam arm.
3. Installation: CRITICAL: Match the feedback cam and linkage geometry exactly to the old unit. Mount the new SRI986 to the NAMUR pad or custom bracket. Reconnect the air lines (ensure the supply goes to the correct port to avoid internal damage).
4. Power-On & Testing: Restore the 4-20mA signal and air supply. Apply 4mA and adjust the zero screw until the valve just begins to move. Apply 20mA and adjust the span screw for full travel. Cycle the signal multiple times to verify smooth, linear response without hunting.

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Can I swap this positioner while the control valve is still online?
Absolutely not. You have to isolate the air supply and electrical signal. If you pull the positioner while the valve is under pressure, you risk a massive process upset or a runaway valve. Always get a maintenance window.Why is my valve hunting or oscillating after installation?
It’s usually a mechanical issue, not an electrical one. Check the feedback linkage for binding or excessive play. If the cam isn’t seated properly or the linkage is loose, the positioner will constantly overcorrect. Also, verify your air supply is clean and dry; moisture in the pilot valve causes erratic behavior.What does the “-C” suffix at the end of the model number mean?
In ECKARDT nomenclature, suffixes like “-C” often denote specific manufacturing revisions, conformal coatings for harsh environments, or regional certification variants. If you are replacing an exact “-C” unit, try to match it. If you must use a base model, verify the environmental rating meets your site’s safety requirements.Is this unit intrinsically safe for Class 1 Div 1 areas?
Yes, the SRI986 series carries ATEX, FM, and CSA intrinsically safe certifications. However, you must ensure the associated safety barriers in the control room are correctly rated and that the field wiring capacitance and inductance do not exceed the certified limits. Always check the safety control drawing.How do I adjust the damping if the valve is reacting too fast?
The SRI986 has an adjustable damping mechanism. If the valve is reacting too aggressively to minor signal noise, increase the damping. But be careful: too much damping will cause the valve to lag during large step changes. Find the sweet spot where it filters out noise but still responds to actual process demands.