Foxboro BS805MD Electrode Kit

Configured for electrochemical measurement loops in Foxboro 871PH sensor assemblies, the Foxboro BS805MD (BS805MD Electrode Kit) provides direct physical fluid-to-electrode contact via flat glass pH sensing elements, titanium wetted parts, and a rugged Ryton body structure.

Hardware Specifications

Foxboro Process Control and 4-20 mA Loop Integration

Operating within electrochemical analytical loops in Foxboro DCS architectures, the BS805MD electrode kit interfaces directly with preamplifier and transmitter electronics to convert hydrogen ion activity into a millivolt signal. While process control loops routinely transmit data via 4-20 mA HART protocol or FOUNDATION Fieldbus links, pH measurement relies on high-impedance electrical signal generation where cable capacitance and ground leakage must be strictly minimized. The titanium wetted parts and durable Ryton body construction ensure chemical resistance and channel isolation against aggressive process media, preserving analytical signal integrity within industrial process streams.

Frequently Asked Questions

Q: Can the BS805MD electrode kit be replaced while the 871PH sensor assembly remains inserted in a pressurized process line?

A: Hot-extracting pH electrodes from pressurized process lines without isolation valves or retractable process fittings can result in chemical exposure and process leakage; always depressurize and isolate the sample point prior to maintenance.

Q: What precautions are required when handling the flat glass pH element during installation?

A: Avoid touching or abrading the flat glass surface with hard objects; contamination or physical micro-fractures on the glass membrane will cause calibration drift and reading errors.

Q: How do titanium wetted parts contribute to measurement stability in corrosive streams?

A: Titanium wetted parts prevent galvanic corrosion and localized pitting when exposed to aggressive chemical process fluids, maintaining a stable reference ground path for the electrode cartridge.

Field Installation Guidelines

• Rinse the electrode cartridge with deionized water and inspect the flat glass membrane and O-ring seals for physical defects before insertion into the 871PH housing.
• Ensure proper alignment of the electrode indexing pins with the sensor body slots to prevent bending or shearing of internal electrical contact pins.
• Torque threaded retaining caps securely according to manufacturer specifications to maintain fluid-tight sealing under maximum process pressure ratings.
• Perform a standard two-point buffer calibration on the transmitter electronics after installation to account for baseline electrode potential shifts.