Switching the show on to pressure measurement

Following 10 years of development, SI Pressure Instruments (enter 370 on enquiry card) has re-specified and redesigned the PC3 pressure calibrator with the launch of the PC6, which has full calibration certification traceable to NAMAS.

The new model incorporates data-logging facilities, and state-of-the-art analogue and digital technology producing a 16bit resolution. Standard accuracy is quoted at 0.05%FS up to 700bar, with options up to 0.01%FS. The unit is also shipped with SI's hand-held test systems, the TP1 Pneumatic and HTP1 Hydraulic offering pressures of -1 to 25bar and 0-700bar respectively. Voltage measurement range is 0-100mV, 0-5Vdc and 0-50Vdc coupled with current measurement range of 0-50mAdc.

Simultaneous functions are displayed with data file access, while timed/event storage with date and time stamping facilities can be sent remotely via RS232 link. Leak measurements are made over a scale between one second and 999 days.

Tare and pressure offset value are displayed alongside a display hold facility, and all measurement data can be imported to an optional SiCal software application for remote control and automatic data logging onto calibration certificate. See SI on stand A40.

HNL Instruments and Controls (371) on stand C30 is using the show as the launchpad for an electronic pressure switch, based on technology used in its SMARTSTAT range.

Microprocessor controlled, the Series 800 pressure switch is said to offer a higher accuracy than its mechanical counterparts, with repeatability of around 0.1%. Switching points are variable through the range with switching resolution quoted at 0.5%. Pressure ranges are from -1 to 1000barg, with a choice of wetted parts and connections.

The Sunx range of electronic pressure sensors from Japan is currently making its UK debut via distributor Allen Bennett Controls (372) on stand P40.

All 21 models in the range are designed for use with non-corrosive gases and are equipped with both digital and analogue outputs and are programmable to display in all commonly used units of pressure. Seven of the units are designed for measuring negative pressures down to 100kPa (14.5psi), with the remaining units for use with positive pressures up to 1mPa (145psi).

There is also the DMM from Rayleigh Instruments (373), stand P44, which is a fully programmable pressure switch and transmitter with integral LED display offering two relay outputs, an analogue output of either 4 2OmA, 0-5V or 0-10V and optional RS232C serial interface.

A range of three new low pressure options has been added to the UCC Pressure Transducers and Transmitters (374) range. 0-1. 0-6 and 0-10bar ratings are available in the 0-100mV transducer and 4-20mA transmitter, both designed with an all stainless steel construction, combined with Micro Plug electrical connections for easy installation. See UCC on stand F210.

In addition to new pressure sensors and instruments, Druck Group (375) has a development, on stand G130, which is said to expand the pressure calibration of its laboratory and field testers from 700 to 2.5mbar, absolute or differential. Models with this new technology include the DPI 145 multi-function pressure indicator, the field portable DPI 605 and DPI 610 calibrators, which employ the LPM 2000 and 9000 series low pressure sensors. A hand-held pressure indicator, the DPI 705, is also making its debut. Designed for general field or workshop applications, it ranges from 70mbar to 700 bar and is supplied with optional hand-pump.

Other products on the Druck stand include the Ruska and Pressurements ranges of pressure calibration standards, including deadweight testers and pressure controllers, and the Druck pressure transducers and transmitters, including the STX 2000 series smart transmitter.

During demonstrations of the award-winning Protran PR9500 non-wired, pressure transmitter on Ellison Sensors' (376) stand P10, visitors will be asked to put the product to the test. The transmitter has a built-in radio, which can send data signals up to 500m in line of sight. There is no hard wiring, which the company says aids installation and cuts down on maintenance. Suitable for hazardous or inaccessible environments, the PR9500 comes in a 316L grade stainless steel housing, which conforms with IP66. Features include: analogue and digital electronics, with silicon on sapphire tech-nology; pressure ranges of 0 to 500mbar to 0 to 1500bar, and a wide screwcap for ease of access for making zero or span adjustments. The transmitter is powered by an internal lithium battery or an external sealed lead acid battery. Transmission frequency is 418mHz, with a 10kHz band width, giving an accuracy better than 0.2 per cent in final output.

The PR9500 was a winner of Stage 1 and Stage 2 SMART awards, and finalist in the Manufacturing Industry Achievement Awards for design and innovation.

Keller's (377) series 53/55 pressure transducers, on stand on P66, come with built-in microprocessors which are said to eliminate errors caused by non-linearity and thermal effects. The microprocessor maps the characteristics over the total pressure/temperature envelope and corrects for them.

These 'smart' transmitters can be interrogated or re-programmed using a standard laptop or PC. The company says that no special knowledge or equipment is required.

Signals from the piezo-resistive pressure sensor and a temperature sensor are digitised by the Keller 'SensoBrain' signal processor and communicated to a microprocessor. The microprocessor is said to calculate true pressure value at actual temperature to give a high accuracy performance over the total temperature range. Typical total error band is 0.1% FS over a 50degC range. As an option, individual transmitters can be equipped with data recording.

Measuring ranges offered are -0.5 to 1000bar in absolute gauge or differential modes. Outputs available are 4-20mVA (2-wire), 0-10V and digital RS 485 (bus capable).