Brand: SHAW Instruments

SHAW SDT-Ex Intrinsically Safe Dew Point Transmitter

Name: SHAW SDT-Ex Dew Point Transmitter – Datasheet & Price Quote
Brand: SHAW Instruments
SKU: SDT-Ex

Description

An intrinsically safe two-wire style dew point transmitter for dry gas and compressed air

The SHAW SDT-Ex is a compact, 3-wire, 4-20 mA dew point transmitter for continuous measurement of trace moisture in dry compressed air and industrial process gases, with hydrocarbon, petrochemical and hydrogen applications named by the manufacturer. It uses the SHAW ultra high capacitance aluminium oxide sensor and is certified intrinsically safe to ATEX and IECEx for use in hazardous areas with a signal isolator. It runs from a 7 to 28 VDC non-isolated supply and keeps a linear 4-20 mA signal for distances up to 1,000 metres. The transmitter is supplied with a certificate of calibration traceable to NPL, an instruction manual and 2 metres of cable.

Technical specifications

Parameter	Specification
Sensing element	SHAW ultra high capacitance aluminium oxide sensor
Ranges (dew point, 0.1 degrees C resolution)	ZD -100 to +20 degrees C; HD -65 to +20 degrees C; P -100 to 0 degrees C (0-6,000 ppmV); S -100 to -20 degrees C (0-1,000 ppmV); G -80 to 0 degrees C; R -80 to -20 degrees C; B -80 to +20 degrees C (0-23,000 ppmV)
Moisture-content ranges	MP 0.1 to 100.0 ppmV; LP 0.01 to 10.00 ppmV; GH 0.01 to 10.00 g/m3; LB 0.1 to 100.0 lb/MMSCF
Accuracy and repeatability	Plus or minus 2 degrees C dew point (NPL traceable, -90 to +20 degrees C); repeatability better than plus or minus 0.3 degrees C
Output	Linear 4-20 mA, configurable in degrees C or F dew point, ppmV, ppbV, g/m3 and lb/MMSCF; resolution 0.016 mA
Supply	7 to 28 VDC, reverse polarity protected; maximum loop resistance = 40 x (supply voltage – 7) ohms
Fault signalling	Open circuit or under range 20.5 mA; short circuit or over range 20.75 mA
Response time	Wet to dry (-20 to -60 degrees C) under 120 s; dry to wet (-100 to -20 degrees C) under 20 s
Operating pressure	1 kPa (0.01 barA) to 35,000 kPa (350 barA)
Sample flow	Flow independent; ideally 2 to 5 litres per minute, maximum 25 litres per minute
Operating and storage temperature	-20 to +60 degrees C; -20 to +70 degrees C
Intrinsic safety	ATEX II 1 GD Ex ia IIC T4 Ga; IECEx Ex ia IIIC T200 135 degrees C Da; -20 degrees C to +60 degrees C ambient
Enclosure and materials	Hard anodised aluminium body, IP66/NEMA 4X when the DIN EN 175301 connector is mated; 316 stainless steel wetted parts; 50 micron 316 sintered filter
Mechanical connection and weight	3/4 inch UNF with Viton O-ring; about 250 g with connector
Manufacturer warranty (per SHAW data sheet)	24 months mechanical; 12 months calibration; terms for an order are confirmed in the quotation

Ordering the SDT-Ex

Order as SDT-Ex followed by the range letter, for example SDT-Ex-G for a -80 to 0 degrees C grey sensor. A separate sensor holder is ordered as SDT-SEH with a fitting code: 4 for 1/4 inch, 8 for 1/8 inch or 6 for 6 mm. The AutoCal facility allows field span checking using a potentiometer on the transmitter body. Because the transmitter is intrinsically safe only when used with a signal isolator, an isolator and loop-powered display are listed among the accessories.

What to confirm before ordering

Confirm the dew point range, the output unit, the hazardous area classification, the isolator in the loop and the sampling arrangement; SHAW lists the SU4 sample conditioning unit for wall mounting. A SHAW portable alternative on this site is the SHAW SDHmini-Ex, and more instruments are under Gas Analyzer Systems. The attached SHAW data sheet contains the full specification and ordering information.

Datasheets & Documents

Datasheet SHAW SDT-Ex Dewpoint Transmitter data sheet Download

Reviews (0)

Reviews

There are no reviews yet.

How would you rate this product?

About brand

Shaw Moisture Meters has made dewpoint meters and trace moisture hygrometers in Bradford since 1960, and many users simply call the instruments SHAW meters. Seven Star LLC supplies SHAW dewpoint instruments to plants in Oman. One of the models listed on this page is the SADP automatic dewpoint meter, a portable unit that technicians carry to a sample point to check how dry a gas or compressed air line is.

SHAW dewpoint meters and how they are used

The SADP is a portable hygrometer for spot checks. A small sample flow passes over the sensor in the instrument head, and the reading is taken at the sample point. Typical checks are instrument air after a dryer, nitrogen and other industrial gases. SHAW also makes the hand-held SDHmini and the intrinsically safe SDHmini-Ex, the fixed Superdew 3 hygrometer and the AcuDew and SDT-Ex dewpoint transmitters for continuous measurement.

Ordering a SHAW dewpoint meter: what we need

A SHAW meter is defined by its sensor range. State the driest and wettest dewpoint you expect, the gas, the line pressure at the sample point and the display units wanted (°C or °F dewpoint, ppm). For a replacement or a spare sensor, send the model and serial number from the instrument label. We supply to the GCC and provide the manufacturer's documents on request.

Browse SHAW Instruments products by category: Gas Analyzer Systems.