Product Overview
The WIKA-ST SP007 SPD is a wet/wet differential pressure transducer: two process connections, the medium on both, one Δp signal out — the basis for orifice flow, filter and strainer condition, sealed-vessel level, and pump discharge-versus-suction. It measures 0–1 to 0–500 psid at 0.25% FSO (0.1% high-accuracy) while sitting on a line up to 500 psi static, with amplified 4–20 mA or voltage output and the port and termination built to order. Have a legacy tecsis part number for this measurement? Send it — WIKA acquired tecsis and now ships these under WIKA Sensor Technology, and we cross-reference the tecsis p/n to the current WIKA-ST equivalent at the same spec.
Key Features & Benefits
- Reports the difference directly — two ports, one reading — the low side subtracts from the high side inside the transducer, so you get the Δp in one signal instead of two single-ended gauges and arithmetic in the controller. One sensor, one number, no subtraction in the PLC.
- Holds the small difference under full line pressure — the wet/wet build withstands the full static line on both ports while still resolving a small differential across them — the hard part of a DP measurement done in the sensor. Resolves a few psid while sitting on hundreds of psi of line.
- Configured like the SP007 it is built on — range, output, port, and termination are all order codes — a dozen port styles and five terminations — so the transducer arrives matching the installation instead of the installation adapting to it. Spec it to the fitting you already have.
Specifications
- Sensing principle
- Strain-gauge wet/wet differential sensing — two process connections, one high and one low, with the medium contacting both ports; the transducer subtracts internally and reports the difference (Δp) as one signal. Built on the customer-configured SP007 platform.
- Pressure type
- Differential (Δp), wet/wet — both ports see the process liquid or gas.
- Measuring range
- 0–1 to 0–500 psid; standard range codes 1, 5, 15, 30, 50, 100, 300, and 500 psid.
- Accuracy
- 0.25% FSO standard; 0.1% FSO on the high-accuracy option.
- Thermal effects
- Temperature error band ±1.5% FSO standard; ±1.0% FSO on the high-accuracy option; extended compensated range available.
- Output signal
- 4–20 mA, 0–5 V, or 0–10 V amplified; optional shunt calibration (specify at order).
- Excitation / supply
- 9–28 VDC (15–28 VDC for the 0–10 V output).
- Electrical connection
- Termination to order: 5-ft polyurethane cable, PTIH-10-6P (or equivalent) 6-pin connector, 1/2 NPT conduit fitting with cable, DIN 43650 form A, or mini-DIN.
- Wetted parts material
- Stainless steel.
- Process connection
- Port to order: 1/4 NPT or 1/8 NPT (female or male), 7/16-20 UNF (MS33649-4 female or MS33656-4 male), G1/4 (female or male), M12×1.5, or 9/16-18 SAE (SAE J1926).
- Overpressure / proof
- Safe overpressure 3× full scale.
- Line (static) pressure
- 500 psi maximum line (static) pressure — the spec to check alongside the differential range.
- Operating temperature
- −40 to +240°F.
- Compensated temperature
- +40 to +140°F (extended compensated range optional).
- Approvals & certification
- CE. Options: extended temperature compensation, shunt calibration, zero and span pots, high-accuracy class.
- Configuration & lead time
- Configured per the differential range, the maximum line pressure, the output, the port, and the termination. Quote-only, no public price list.
Common Applications
- Orifice / flow-element differential for flow measurement
- Filter and strainer condition monitoring — Δp rises as the element loads
- Liquid level in a sealed or pressurized vessel by differential head
- Pump discharge-versus-suction and system Δp
Design & Selection Considerations
- A DP selection needs two pressures, not one — specify the differential range AND the maximum line (static) pressure separately. The SPD holds 500 psi of static while resolving a few psid across it; pick a unit whose line-pressure rating covers your highest static condition, not just the Δp you expect to read. Forget the line pressure and the sensor is overpressured the day the system is at rest.
- FSO accuracy is a percentage of the range, not the reading — a ±0.25% FSO transducer rated for the full scale can be off by that fraction of full scale anywhere in its range — a larger relative error down at the low end. Size so the working pressure lands in the upper part of the range, and when you compare two sensors make sure both quote accuracy the same way. An oversized range quietly throws away resolution at the pressure you actually run.
- Respect the overpressure limit — the danger zone is below burst — proof / safe-overpressure is the pressure the sensor can see without losing calibration; burst is where it is destroyed. A unit driven past proof but short of burst keeps reporting plausible, wrong numbers. Size for the real worst case — including transients — and recalibrate after any suspected overpressure event. A spike that shifts calibration leaves no visible mark; the reading just drifts.
- Match the wetted material to the medium — the wetted parts see the process chemistry directly; the standard stainless suits most service, but corrosive, high-purity, or sour media want the right alloy specified up front. Use the input form to tell us the medium and we pick the wetted material to it. The wrong wetted alloy fails slowly and silently, not all at once.
To spec the right WIKA-ST wet/wet differential transducer:
To size and select the right transducer, send us: the pressure range and whether it is gauge, absolute, sealed, or differential; for a differential measurement, the maximum line (static) pressure as well as the differential range; the accuracy class you need (standard industrial vs. high-accuracy); the output the receiving device expects (4–20 mA, 0–5 V, 0–10 V, or raw mV/V) and the cable run; the process medium and temperature (so the wetted material and any extended temperature compensation are right); the process connection and electrical termination; and any area classification or agency approval (Ex / intrinsic safety, CSA, FM) and NACE / sour-service material requirement. For a fast transient, give us the rise time or frequency of the event so the natural frequency is sized above it.
Force & Pressure Application Sheet ›Talk to an engineer directly — Scott Prater, Principal · 917-580-0878 · scott@pratertechnical.com
Specifications compiled by Prater Technical Partners from WIKA product datasheets.