The ABB 266DDHFSSA2B7LSI2H3+S26RAHG1SFSM2N1SNNN is a differential pressure transmitter paired with a rotating flange diaphragm seal — a configured assembly for DP measurement on processes requiring a flush or extended diaphragm seal to ASME B16.5. The transmitter side carries a base accuracy of 0.06 %, which means the measurement uncertainty stays under six hundredths of a percent of the calibrated span; for a 40 kPa span that is roughly 24 Pa of error. The seal side is a S26RA rotating flange design, flush-mount, rated ASME CL150 at 3-inch size, with AISI 316L SS diaphragm and PTFE-faced bolts/gasket. Span limits are set to 0.67 and 40 kPa (6.7 to 400 mbar), so this variant is suited for low-to-moderate differential ranges — common on filter monitoring, level measurement on closed tanks, or flow across an orifice plate. The fill fluid is silicone oil DC200 10 cSt, standard for clean process fluids; the direct-mount construction (capillary length = 1, direct mount) eliminates the capillary run and keeps the seal rigidly attached to the transmitter.
The assembly includes material traceability per EN 10204-3.1 for the process-wetted parts (inspection certificate), which covers the diaphragm, flange, and seal face. That certification is baked into the order code via the H3 suffix — no separate paperwork request needed.
The transmitter housing is an aluminium alloy barrel with M20 x 1.5 electrical connection (CM20). That is the standard metric conduit entry for European panels; if your panel uses 1/2 NPT, you will need an adapter. The seal mounts on the high-pressure side of the process (H = high-pressure side connection), with a flush diaphragm and smooth surface finish (Seal Surface Finish = 2, smooth). No flushing ring is included (N = none). If the process fluid is prone to buildup or requires periodic flushing, you will need to order a flushing ring separately. The direct-mount design means the seal bolts directly to the transmitter manifold — no capillary tubing to route, which simplifies panel layout and reduces the risk of mechanical damage during installation.
What the Config Code Tells You
The full order code breaks down into two halves: the transmitter (266DDHFSSA2B7LSI2H3) and the seal (S26RAHG1SFSM2N1SNNN). The transmitter half specifies the sensor span (F = 0.67-40 kPa), housing (B = aluminium barrel M20x1.5), wetted diaphragm material (S = AISI 316L SS with silicone oil fill), process connection (A = AISI 316L SS, 1/4-18 NPT-f horizontal), and the material traceability (H3). The seal half specifies the rotating flange design (S26RA), ASME CL150 / 3 in. rating (G1), flush diaphragm (F), AISI 316 SS flange material (S), PTFE bolts/gasket (2), and no flushing ring (N). The additional tag plate (I2) means a laser-engraved stainless steel tag is attached — useful for permanent identification in the field.