025-29148-019 Pressure Transducer Danfoss

025-29148-019 Application Case
This item is a York condensing pressure transmitter, model PENN P499REAB517C, with a range of 4–34 PSIA (absolute pressure), 4.75–5.25 VDC power supply, and a proportional output of 0.5–4.5 VDC. It is mainly installed at the pressure measurement port of the condenser of York centrifugal chiller (YK series).
Typical Application 1: Condensing Pressure Control. The OptiView Control Center converts the real-time condensing pressure from 4 psia to 0.5 V, and from 34 psia to 4.5 V. Based on this, it adjusts the frequency of the cooling pump and the rotational speed of the cooling tower fan. During winter or low-load conditions, the condensing pressure can be as low as below 10 psia. Ordinary 0–400 psi transmitters are insufficient in resolution in this range, and low head control can become unstable and cause surge - this is why -019 adopts a narrow range of absolute pressure design.
Application 2: Low Temperature Refrigeration and Low Pressure Protection. The absolute pressure reference is not affected by altitude and changes in atmospheric pressure. The readings are consistent between high-altitude and coastal units, and are combined with low condensing pressure alarms and refrigerant leakage detection.
Application 3: Frequency/Blade Linkage. The 4 ms response keeps up with load transients, providing feedback for the unit's load increase/decrease and anti-surge prevention.