5123130010 Schneider STP200-50 Liquid Line Thermo Element 50mm Stem 10k Ohm Curve 2 Pocket Well

Why this part exists: Every hydronic control loop inherits the accuracy of the probe that feeds it, which is why the 5123130010 is treated as a measurement instrument rather than an accessory. Catalogued by Schneider Electric inside the STP200 (10 kOhm, curve type 2) range, it carries a stainless-steel stem that is lowered into the water stream through a separate closed pocket, so the sensing element can be swapped during maintenance without draining the circuit.

Behind the stem, a moulded, sealed transition separates wet metal from the cable, and the factory-fitted gland protects against condensation, dust, and wash-down spray. As a passive device, it draws no meaningful current, requires no firmware updates, and has no battery replacement schedule. Each unit is checked against traceable temperature references before packing, with documentation suitable for commissioning records and energy audits.

How this variant is chosen: Start with the pocket, not the probe. The 50 mm stem is ideal for small pipes, shallow pockets, or crowded risers with fittings—typical in terminal units, fan-coil branches, and compact heat exchangers.

• Part number: 5123130010
• Product code: STP200-50
• Product family: STP200 (10 kOhm, curve type 2)
• Sensing element: Passive 10 kOhm thermistor, curve type 2
• Signal path / wiring: Two/three-wire resistance loop to controller analogue input
• Supply: None required; excited by controller measuring circuit
• Probe length: 50 mm (1.97 in.)
• Temperature range: Chilled and hot water duty per STP200 curve
• Accuracy: Matched to standard HVAC control grade
• Mounting: Immersion through separate closed pocket (pocket ordered separately)
• Stem material: Stainless steel, corrosion resistant
• Cable: 2 m PVC-sheathed flying lead with 20 mm (0.79 in.) fitting and gland
• Housing: Sealed plant-room construction, IP-rated against condensation
• Response: Curve matched to host controller input
• Approvals: CE, RoHS, REACH; Schneider Green Premium documentation

The 50 mm stem is particularly suited for refurbished risers where original installations used shallow pockets and re-drilling isn't practical. This ensures the sensing element contacts flowing water rather than dead air, providing accurate readings to the controller.

Applied to fan-coil branches and small heat exchangers, it enables precise valve modulation that tracks real load conditions. Specifiers also select this length for modular plant skids where stem clearance is critical during assembly and surrounding pipework restricts longer insertion options.